Merge branch 'dev-widget' into release-1.4

Conflicts:
	calculatorpp/AndroidManifest.xml

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorButtonActions.java

@@ -0,0 +1,13 @@
+package org.solovyev.android.calculator;
+
+/**
+ * User: Solovyev_S
+ * Date: 19.10.12
+ * Time: 17:31
+ */
+public final class CalculatorButtonActions {
+
+    private CalculatorButtonActions() {
+        throw new AssertionError();
+    }
+}

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorDisplayViewState.java

@@ -5,12 +5,14 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.calculator.jscl.JsclOperation;
 
+import java.io.Serializable;
+
 /**
  * User: serso
  * Date: 9/20/12
  * Time: 9:50 PM
  */
-public interface CalculatorDisplayViewState {
+public interface CalculatorDisplayViewState extends Serializable {
 
     @NotNull
     String getText();

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorDisplayViewStateImpl.java

@@ -13,11 +13,19 @@ import org.solovyev.common.text.StringUtils;
  */
 public class CalculatorDisplayViewStateImpl implements CalculatorDisplayViewState {
 
+    /*
+    **********************************************************************
+    *
+    *                           FIELDS
+    *
+    **********************************************************************
+    */
+
     @NotNull
     private JsclOperation operation = JsclOperation.numeric;
 
     @Nullable
-    private Generic result;
+    private transient Generic result;
 
     @Nullable
     private String stringResult = "";
@@ -29,6 +37,14 @@ public class CalculatorDisplayViewStateImpl implements CalculatorDisplayViewStat
 
     private int selection = 0;
 
+    /*
+    **********************************************************************
+    *
+    *                           CONSTRUCTORS
+    *
+    **********************************************************************
+    */
+
     private CalculatorDisplayViewStateImpl() {
     }
 
@@ -62,6 +78,14 @@ public class CalculatorDisplayViewStateImpl implements CalculatorDisplayViewStat
         return calculatorDisplayState;
     }
 
+    /*
+    **********************************************************************
+    *
+    *                           METHODS
+    *
+    **********************************************************************
+    */
+
     @NotNull
     @Override
     public String getText() {

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorEditorImpl.java

@@ -65,7 +65,7 @@ public class CalculatorEditorImpl implements CalculatorEditor {
         setViewState(newViewState, true);
     }
 
-    private void setViewState(@NotNull CalculatorEditorViewState newViewState, boolean fireEvent) {
+    private void setViewState(@NotNull CalculatorEditorViewState newViewState, boolean majorChanges) {
         synchronized (viewLock) {
             final CalculatorEditorViewState oldViewState = this.lastViewState;
 
@@ -74,8 +74,10 @@ public class CalculatorEditorImpl implements CalculatorEditor {
                 this.view.setState(newViewState);
             }
 
-            if (fireEvent) {
+            if (majorChanges) {
                 calculator.fireCalculatorEvent(CalculatorEventType.editor_state_changed, new CalculatorEditorChangeEventDataImpl(oldViewState, newViewState));
+            } else {
+                calculator.fireCalculatorEvent(CalculatorEventType.editor_state_changed_light, new CalculatorEditorChangeEventDataImpl(oldViewState, newViewState));
             }
         }
     }

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorEditorViewState.java

@@ -2,12 +2,14 @@ package org.solovyev.android.calculator;
 
 import org.jetbrains.annotations.NotNull;
 
+import java.io.Serializable;
+
 /**
  * User: Solovyev_S
  * Date: 21.09.12
  * Time: 11:48
  */
-public interface CalculatorEditorViewState {
+public interface CalculatorEditorViewState extends Serializable {
 
     @NotNull
     String getText();

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorEventType.java

@@ -58,6 +58,7 @@ public enum CalculatorEventType {
 
     // @NotNull org.solovyev.android.calculator.CalculatorEditorChangeEventData
     editor_state_changed,
+    editor_state_changed_light,
 
     // @NotNull CalculatorDisplayChangeEventData
     display_state_changed,
@@ -112,7 +113,33 @@ public enum CalculatorEventType {
     constant_changed,
 
     // @NotNull IConstant
-    constant_removed;
+    constant_removed,
+
+    /*
+    **********************************************************************
+    *
+    *                           OTHER
+    *
+    **********************************************************************
+    */
+    show_history,
+    show_history_detached,
+
+    show_functions,
+    show_functions_detached,
+
+    show_vars,
+    show_vars_detached,
+
+    open_app,
+
+    show_operators,
+    show_operators_detached,
+
+    show_settings,
+    show_settings_detached,
+
+    show_like_dialog;
 
     public boolean isOfType(@NotNull CalculatorEventType... types) {
         for (CalculatorEventType type : types) {

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorImpl.java

@@ -409,17 +409,17 @@ public class CalculatorImpl implements Calculator, CalculatorEventListener {
 
             case use_constant:
                 final IConstant constant = (IConstant)data;
-                CalculatorLocatorImpl.getInstance().getKeyboard().digitButtonPressed(constant.getName());
+                CalculatorLocatorImpl.getInstance().getKeyboard().buttonPressed(constant.getName());
                 break;
 
             case use_operator:
                 final Operator operator = (Operator)data;
-                CalculatorLocatorImpl.getInstance().getKeyboard().digitButtonPressed(operator.getName());
+                CalculatorLocatorImpl.getInstance().getKeyboard().buttonPressed(operator.getName());
                 break;
 
             case use_function:
                 final Function function = (Function)data;
-                CalculatorLocatorImpl.getInstance().getKeyboard().digitButtonPressed(function.getName());
+                CalculatorLocatorImpl.getInstance().getKeyboard().buttonPressed(function.getName());
                 break;
 
         }

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorKeyboard.java

@@ -9,7 +9,7 @@ import org.jetbrains.annotations.Nullable;
  */
 public interface CalculatorKeyboard {
 
-    void digitButtonPressed(@Nullable String text);
+    void buttonPressed(@Nullable String text);
 
     void roundBracketsButtonPressed();
 

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorKeyboardImpl.java

@@ -20,40 +20,57 @@ public class CalculatorKeyboardImpl implements CalculatorKeyboard {
     }
 
     @Override
-    public void digitButtonPressed(@Nullable final String text) {
+    public void buttonPressed(@Nullable final String text) {
 
         if (!StringUtils.isEmpty(text)) {
             assert text != null;
 
-            int cursorPositionOffset = 0;
+            // process special buttons
-            final StringBuilder textToBeInserted = new StringBuilder(text);
+            boolean processed = processSpecialButtons(text);
 
-            final MathType.Result mathType = MathType.getType(text, 0, false);
+            if (!processed) {
-            switch (mathType.getMathType()) {
+                int cursorPositionOffset = 0;
-                case function:
+                final StringBuilder textToBeInserted = new StringBuilder(text);
-                    textToBeInserted.append("()");
-                    cursorPositionOffset = -1;
-                    break;
-                case operator:
-                    textToBeInserted.append("()");
-                    cursorPositionOffset = -1;
-                    break;
-                case comma:
-                    textToBeInserted.append(" ");
-                    break;
-            }
 
-            if (cursorPositionOffset == 0) {
+                final MathType.Result mathType = MathType.getType(text, 0, false);
-                if (MathType.openGroupSymbols.contains(text)) {
+                switch (mathType.getMathType()) {
-                    cursorPositionOffset = -1;
+                    case function:
+                        textToBeInserted.append("()");
+                        cursorPositionOffset = -1;
+                        break;
+                    case operator:
+                        textToBeInserted.append("()");
+                        cursorPositionOffset = -1;
+                        break;
+                    case comma:
+                        textToBeInserted.append(" ");
+                        break;
                 }
-            }
 
-            final CalculatorEditor editor = CalculatorLocatorImpl.getInstance().getEditor();
+                if (cursorPositionOffset == 0) {
-            editor.insert(textToBeInserted.toString(), cursorPositionOffset);
+                    if (MathType.openGroupSymbols.contains(text)) {
+                        cursorPositionOffset = -1;
+                    }
+                }
+
+                final CalculatorEditor editor = CalculatorLocatorImpl.getInstance().getEditor();
+                editor.insert(textToBeInserted.toString(), cursorPositionOffset);
+            }
         }
     }
 
+    private boolean processSpecialButtons(@NotNull String text) {
+        boolean result = false;
+
+        final CalculatorSpecialButton button = CalculatorSpecialButton.getByActionCode(text);
+        if ( button != null ) {
+            button.onClick(this);
+            result = true;
+        }
+
+        return result;
+    }
+
     @Override
     public void roundBracketsButtonPressed() {
         final CalculatorEditor editor = CalculatorLocatorImpl.getInstance().getEditor();

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorNotifier.java

@@ -19,4 +19,6 @@ public interface CalculatorNotifier {
     void showMessage(@NotNull Integer messageCode, @NotNull MessageType messageType, @NotNull List<Object> parameters);
 
     void showMessage(@NotNull Integer messageCode, @NotNull MessageType messageType, @Nullable Object... parameters);
+
+    void showDebugMessage(@Nullable  String tag, @NotNull String message);
 }

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorSpecialButton.java

@@ -0,0 +1,155 @@
+package org.solovyev.android.calculator;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * User: serso
+ * Date: 10/20/12
+ * Time: 2:05 PM
+ */
+public enum CalculatorSpecialButton {
+
+    history("history") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_history, null);
+        }
+    },
+    history_detached("history_detached") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_history_detached, null);
+        }
+    },
+    cursor_right("▶") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            keyboard.moveCursorRight();
+        }
+    },
+    cursor_left("◀") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            keyboard.moveCursorLeft();
+        }
+    },
+    settings("settings") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_settings, null);
+        }
+    },
+
+    settings_detached("settings_detached") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_settings_detached, null);
+        }
+    },
+
+    like("like") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_like_dialog, null);
+        }
+    },
+    erase("erase") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getEditor().erase();
+        }
+    },
+    paste("paste") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            keyboard.pasteButtonPressed();
+        }
+    },
+    copy("copy") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            keyboard.copyButtonPressed();
+        }
+    },
+    equals("=") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().evaluate();
+        }
+    },
+    clear("clear") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            keyboard.clearButtonPressed();
+        }
+    },
+    functions("functions") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_functions, null);
+        }
+    },
+    functions_detached("functions_detached") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_functions_detached, null);
+        }
+    },
+    open_app("open_app") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.open_app, null);
+        }
+    },
+    vars("vars") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_vars, null);
+        }
+    },
+    vars_detached("vars_detached") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_vars_detached, null);
+        }
+    },
+    operators("operators") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_operators, null);
+        }
+    },
+
+    operators_detached("operators_detached") {
+        @Override
+        public void onClick(@NotNull CalculatorKeyboard keyboard) {
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_operators_detached, null);
+        }
+    };
+
+    @NotNull
+    private final String actionCode;
+
+    CalculatorSpecialButton(@NotNull String actionCode) {
+        this.actionCode = actionCode;
+    }
+
+    @NotNull
+    public String getActionCode() {
+        return actionCode;
+    }
+
+    @Nullable
+    public static CalculatorSpecialButton getByActionCode(@NotNull String actionCode) {
+        for (CalculatorSpecialButton button : values()) {
+            if (button.getActionCode().equals(actionCode)) {
+                return button;
+            }
+        }
+
+        return null;
+    }
+
+    public abstract void onClick(@NotNull CalculatorKeyboard keyboard);
+}

calculatorpp-core/src/main/java/org/solovyev/android/calculator/DummyCalculatorNotifier.java

@@ -25,4 +25,8 @@ public class DummyCalculatorNotifier implements CalculatorNotifier {
     @Override
     public void showMessage(@NotNull Integer messageCode, @NotNull MessageType messageType, @Nullable Object... parameters) {
     }
+
+    @Override
+    public void showDebugMessage(@Nullable String tag, @NotNull String message) {
+    }
 }

calculatorpp-core/src/main/java/org/solovyev/android/calculator/ListCalculatorEventContainer.java

@@ -42,6 +42,7 @@ public class ListCalculatorEventContainer implements CalculatorEventContainer {
         final CalculatorLogger logger = CalculatorLocatorImpl.getInstance().getLogger();
 
         for (CalculatorEvent e : calculatorEvents) {
+            CalculatorLocatorImpl.getInstance().getLogger().debug(TAG, "Event fired: " + e.getCalculatorEventType());
             for (CalculatorEventListener listener : listeners) {
                 /*long startTime = System.currentTimeMillis();*/
                 listener.onCalculatorEvent(e.getCalculatorEventData(), e.getCalculatorEventType(), e.getData());

calculatorpp-core/src/test/java/org/solovyev/android/calculator/CalculatorDisplayViewStateImplTest.java

@@ -0,0 +1,23 @@
+package org.solovyev.android.calculator;
+
+import jscl.math.Expression;
+import org.junit.Test;
+import org.solovyev.android.calculator.jscl.JsclOperation;
+
+/**
+ * User: serso
+ * Date: 10/20/12
+ * Time: 12:24 PM
+ */
+public class CalculatorDisplayViewStateImplTest {
+
+    @Test
+    public void testSerializable() throws Exception {
+        CalculatorTestUtils.testSerialization(CalculatorDisplayViewStateImpl.newValidState(JsclOperation.numeric, null, "test", 3));
+        CalculatorTestUtils.testSerialization(CalculatorDisplayViewStateImpl.newValidState(JsclOperation.numeric, Expression.valueOf("3"), "test", 3));
+        CalculatorTestUtils.testSerialization(CalculatorDisplayViewStateImpl.newValidState(JsclOperation.simplify, Expression.valueOf("3+3"), "test", 3));
+        CalculatorTestUtils.testSerialization(CalculatorDisplayViewStateImpl.newDefaultInstance());
+        CalculatorTestUtils.testSerialization(CalculatorDisplayViewStateImpl.newErrorState(JsclOperation.numeric, "ertert"));
+    }
+
+}

calculatorpp-core/src/test/java/org/solovyev/android/calculator/CalculatorEditorViewStateImplTest.java

@@ -0,0 +1,21 @@
+package org.solovyev.android.calculator;
+
+import junit.framework.Assert;
+import org.junit.Test;
+
+/**
+ * User: serso
+ * Date: 10/20/12
+ * Time: 12:31 PM
+ */
+public class CalculatorEditorViewStateImplTest {
+
+    @Test
+    public void testSerialization() throws Exception {
+        CalculatorTestUtils.testSerialization(CalculatorEditorViewStateImpl.newDefaultInstance());
+
+        CalculatorEditorViewState out = CalculatorTestUtils.testSerialization(CalculatorEditorViewStateImpl.newInstance("treter", 2));
+        Assert.assertEquals(2, out.getSelection());
+        Assert.assertEquals("treter", out.getText());
+    }
+}

calculatorpp-core/src/test/java/org/solovyev/android/calculator/CalculatorTestUtils.java

@@ -8,6 +8,7 @@ import org.mockito.Mockito;
 import org.solovyev.android.calculator.history.CalculatorHistory;
 import org.solovyev.android.calculator.jscl.JsclOperation;
 
+import java.io.*;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 
@@ -41,7 +42,7 @@ public class CalculatorTestUtils {
     }
 
     public static void assertEval(@NotNull String expected, @NotNull String expression) {
-       assertEval(expected, expression, JsclOperation.numeric);
+        assertEval(expected, expression, JsclOperation.numeric);
     }
 
     public static void assertEval(@NotNull String expected, @NotNull String expression, @NotNull JsclOperation operation) {
@@ -57,8 +58,8 @@ public class CalculatorTestUtils {
             calculatorEventListener.setCalculatorEventData(calculator.evaluate(operation, expression));
 
             if (latch.await(TIMEOUT, TimeUnit.SECONDS)) {
-               Assert.assertNotNull(calculatorEventListener.getResult());
+                Assert.assertNotNull(calculatorEventListener.getResult());
-               Assert.assertEquals(expected, calculatorEventListener.getResult().getText());
+                Assert.assertEquals(expected, calculatorEventListener.getResult().getText());
             } else {
                 Assert.fail("Too long wait for: " + expression);
             }
@@ -74,7 +75,33 @@ public class CalculatorTestUtils {
         assertError(expression, JsclOperation.numeric);
     }
 
-    private static final class TestCalculatorEventListener implements  CalculatorEventListener {
+    public static <S extends Serializable> S testSerialization(@NotNull S serializable) throws IOException, ClassNotFoundException {
+        final ByteArrayOutputStream out = new ByteArrayOutputStream();
+
+        ObjectOutputStream oos = null;
+        try {
+            oos = new ObjectOutputStream(out);
+            oos.writeObject(serializable);
+        } finally {
+            if (oos != null) {
+                oos.close();
+            }
+        }
+
+        byte[] serialized = out.toByteArray();
+
+        Assert.assertTrue(serialized.length > 0);
+
+
+        final ObjectInputStream resultStream = new ObjectInputStream(new ByteArrayInputStream(out.toByteArray()));
+        final S result = (S) resultStream.readObject();
+
+        Assert.assertNotNull(result);
+
+        return result;
+    }
+
+    private static final class TestCalculatorEventListener implements CalculatorEventListener {
 
         @Nullable
         private CalculatorEventData calculatorEventData;
@@ -95,7 +122,7 @@ public class CalculatorTestUtils {
 
         @Override
         public void onCalculatorEvent(@NotNull CalculatorEventData calculatorEventData, @NotNull CalculatorEventType calculatorEventType, @Nullable Object data) {
-            if ( this.calculatorEventData != null && calculatorEventData.isSameSequence(this.calculatorEventData) ) {
+            if (this.calculatorEventData != null && calculatorEventData.isSameSequence(this.calculatorEventData)) {
                 if (calculatorEventType == CalculatorEventType.display_state_changed) {
                     final CalculatorDisplayChangeEventData displayChange = (CalculatorDisplayChangeEventData) data;
 

calculatorpp/AndroidManifest.xml

@@ -11,7 +11,7 @@
 
     <application android:debuggable="false" android:hardwareAccelerated="false" android:icon="@drawable/icon" android:label="@string/c_app_name" android:name=".CalculatorApplication" android:theme="@style/metro_blue_theme">
 
-        <activity android:label="@string/c_app_name" android:name=".CalculatorActivity" android:windowSoftInputMode="adjustPan">
+        <activity android:label="@string/c_app_name" android:name=".CalculatorActivity" android:windowSoftInputMode="adjustPan" android:clearTaskOnLaunch="true">
 
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
@@ -37,9 +37,32 @@
 
         <activity android:label="@string/c_plot_graph" android:name=".plot.CalculatorPlotActivity"/>
 
+        <activity android:name=".widget.CalculatorWidgetConfigurationActivity"  android:theme="@style/metro_blue_theme">
+            <intent-filter>
+                <action android:name="android.appwidget.action.APPWIDGET_CONFIGURE"/>
+            </intent-filter>
+        </activity>
+
         <!-- settings must use action bar icon-->
         <activity android:icon="@drawable/icon_action_bar" android:label="@string/c_settings" android:name=".plot.CalculatorPlotPreferenceActivity"/>
 
+        <receiver
+                android:icon="@drawable/icon"
+                android:label="@string/c_app_name"
+                android:name=".widget.CalculatorWidgetProvider">
+
+            <intent-filter>
+                <action android:name="android.appwidget.action.APPWIDGET_UPDATE"/>
+                <action android:name="org.solovyev.calculator.widget.EDITOR_STATE_CHANGED"/>
+                <action android:name="org.solovyev.calculator.widget.DISPLAY_STATE_CHANGED"/>
+                <action android:name="org.solovyev.calculator.widget.BUTTON_PRESSED"/>
+            </intent-filter>
+
+            <meta-data
+                    android:name="android.appwidget.provider"
+                    android:resource="@xml/calculator_widget_info"/>
+        </receiver>
+
         <activity android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize" android:name="com.google.ads.AdActivity"/>
 
         <service android:name="net.robotmedia.billing.BillingService"/>

calculatorpp/res/layout/calc_copy_button.xml

@@ -8,7 +8,7 @@
 
 <org.solovyev.android.view.ColorButton xmlns:a="http://schemas.android.com/apk/res/android"
 			 xmlns:c="http://schemas.android.com/apk/res/org.solovyev.android.calculator"
-			 a:id="@+id/pasteButton"
+			 a:id="@+id/copyButton"
 			 a:drawableTop="@drawable/kb_copy"
 			 style="?controlImageButtonStyle"
 			 a:onClick="copyButtonClickHandler"/>

calculatorpp/res/layout/calc_dot_button.xml

@@ -8,7 +8,7 @@
 
 <org.solovyev.android.view.drag.DirectionDragButton xmlns:a="http://schemas.android.com/apk/res/android"
 													   xmlns:c="http://schemas.android.com/apk/res/org.solovyev.android.calculator"
-													   a:id="@+id/squareBracketsButton"
+													   a:id="@+id/periodButton"
 													   a:text="."
 													   c:textUp=","
 													   c:directionTextScale="0.5"

calculatorpp/res/layout/calc_left_button.xml

@@ -13,4 +13,4 @@
 													   a:text="◀"
 													   c:directionTextScale="0.5"
 													   style="?controlButtonStyle"
-													   a:onClick="moveLeftButtonClickHandler"/>
+													   a:onClick="digitButtonClickHandler"/>

calculatorpp/res/layout/calc_right_button.xml

@@ -13,4 +13,4 @@
 													   a:text="▶"
 													   c:directionTextScale="0.5"
 													   style="?controlButtonStyle"
-													   a:onClick="moveRightButtonClickHandler"/>
+													   a:onClick="digitButtonClickHandler"/>

calculatorpp/res/layout/widget_app_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<ImageButton xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/appButton"
+        a:src="@drawable/kb_logo"
+        style="@style/widget_metro_control_image_button_style"
+        a:contentDescription="App"/>

calculatorpp/res/layout/widget_clear_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/clearButton"
+        a:text="@string/c_clear"
+        a:textStyle="bold"
+        style="@style/widget_metro_control_button_style"/>

calculatorpp/res/layout/widget_copy_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<ImageButton xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/copyButton"
+        a:src="@drawable/kb_copy"
+        style="@style/widget_metro_control_image_button_style"
+        a:contentDescription="Copy"/>

calculatorpp/res/layout/widget_display.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<TextView
+        xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/calculatorDisplay"
+        style="@style/widget_display_style"
+        a:textIsSelectable="true"
+        a:padding="@dimen/display_padding"
+        a:singleLine="false"
+        a:scrollbars="vertical"/>

calculatorpp/res/layout/widget_division_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/divisionButton"
+        a:text="/"
+        style="@style/widget_metro_blue_operation_button_style"/>

calculatorpp/res/layout/widget_dot_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/periodButton"
+        a:text="."
+        style="@style/metro_digit_button_style"/>

calculatorpp/res/layout/widget_editor.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<LinearLayout xmlns:a="http://schemas.android.com/apk/res/android"
+              a:id="@+id/main_fragment_layout"
+              style="@style/default_fragment_layout_style"
+              a:layout_width="match_parent"
+              a:layout_height="match_parent"
+              a:padding="@dimen/editor_padding">
+
+    <TextView
+            a:id="@+id/calculatorEditor"
+            style="@style/widget_editor_style"
+            a:textIsSelectable="true"
+            a:singleLine="false"
+            a:scrollbars="vertical"
+            a:hint="@string/c_calc_editor_hint"/>
+
+</LinearLayout>

calculatorpp/res/layout/widget_eight_digit_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/eightDigitButton"
+        a:text="8"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_equals_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+<Button
+        xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/equalsButton"
+        a:text="="
+        style="@style/widget_metro_control_button_style"/>

calculatorpp/res/layout/widget_erase_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<ImageButton xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/eraseButton"
+        a:src="@drawable/kb_delete"
+        style="@style/widget_metro_control_image_button_style"
+        a:contentDescription="Erase"/>

calculatorpp/res/layout/widget_five_digit_button.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/fiveDigitButton"
+        a:text="5"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_four_digit_button.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/fourDigitButton"
+        a:text="4"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_functions_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/functionsButton"
+        a:text="ƒ(x)"
+        a:textStyle="italic"
+        style="@style/widget_metro_control_button_style"/>

calculatorpp/res/layout/widget_history_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/historyButton"
+        a:text="@string/c_history_button"
+        style="@style/widget_metro_control_button_style"
+        a:textStyle="bold"/>

calculatorpp/res/layout/widget_keyboard.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<LinearLayout xmlns:a="http://schemas.android.com/apk/res/android"
+              a:layout_width="match_parent"
+              a:layout_height="match_parent"
+              a:orientation="vertical">
+
+    <LinearLayout a:layout_weight="1"
+                  a:layout_width="match_parent"
+                  a:layout_height="0dp">
+
+        <include layout="@layout/widget_seven_digit_button"/>
+        <include layout="@layout/widget_eight_digit_button"/>
+        <include layout="@layout/widget_nine_digit_button"/>
+        <include layout="@layout/widget_multiplication_button"/>
+        <include layout="@layout/widget_percent_button"/>
+        <include layout="@layout/widget_clear_button"/>
+
+    </LinearLayout>
+
+    <LinearLayout a:layout_weight="1"
+                  a:layout_width="match_parent"
+                  a:layout_height="0dp">
+
+        <include layout="@layout/widget_four_digit_button"/>
+        <include layout="@layout/widget_five_digit_button"/>
+        <include layout="@layout/widget_six_digit_button"/>
+        <include layout="@layout/widget_division_button"/>
+        <include layout="@layout/widget_power_button"/>
+        <include layout="@layout/widget_erase_button"/>
+
+    </LinearLayout>
+
+    <LinearLayout a:layout_weight="1"
+                  a:layout_width="match_parent"
+                  a:layout_height="0dp">
+
+        <include layout="@layout/widget_one_digit_button"/>
+        <include layout="@layout/widget_two_digit_button"/>
+        <include layout="@layout/widget_three_digit_button"/>
+        <include layout="@layout/widget_plus_button"/>
+        <include layout="@layout/widget_like_button"/>
+        <include layout="@layout/widget_copy_button"/>
+
+    </LinearLayout>
+
+    <LinearLayout a:layout_weight="1"
+                  a:layout_width="match_parent"
+                  a:layout_height="0dp">
+
+        <include layout="@layout/widget_round_brackets_button"/>
+        <include layout="@layout/widget_zero_digit_button"/>
+        <include layout="@layout/widget_dot_button"/>
+        <include layout="@layout/widget_subtraction_button"/>
+        <include layout="@layout/widget_settings_button"/>
+        <include layout="@layout/widget_paste_button"/>
+
+    </LinearLayout>
+
+
+    <LinearLayout a:layout_weight="1"
+                  a:layout_width="match_parent"
+                  a:layout_height="0dp">
+
+        <include layout="@layout/widget_left_button"/>
+        <include layout="@layout/widget_right_button"/>
+        <include layout="@layout/widget_vars_button"/>
+        <include layout="@layout/widget_functions_button"/>
+        <include layout="@layout/widget_app_button"/>
+        <include layout="@layout/widget_history_button"/>
+
+    </LinearLayout>
+
+</LinearLayout>

calculatorpp/res/layout/widget_layout.xml

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<LinearLayout xmlns:a="http://schemas.android.com/apk/res/android"
+              a:layout_width="match_parent"
+              a:layout_height="match_parent"
+              a:orientation="vertical"
+              style="@style/widget_main_layout_style">
+
+    <include layout="@layout/widget_editor"
+             a:layout_weight="2"
+             a:layout_width="match_parent"
+             a:layout_height="0dp"/>
+
+    <LinearLayout a:layout_weight="1"
+                  a:layout_width="match_parent"
+                  a:layout_height="0dp">
+
+        <include layout="@layout/widget_equals_button"
+                 a:layout_margin="@dimen/button_margin"
+                 a:layout_weight="1"
+                 a:layout_width="0dp"
+                 a:layout_height="match_parent"/>
+
+        <include layout="@layout/widget_display"
+                      a:layout_weight="5"
+                      a:layout_width="0dp"
+                      a:layout_height="wrap_content"/>
+
+    </LinearLayout>
+
+    <include layout="@layout/widget_keyboard"
+             a:layout_weight="5"
+             a:layout_width="match_parent"
+             a:layout_height="0dp"/>
+
+</LinearLayout>

calculatorpp/res/layout/widget_left_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/leftButton"
+        a:text="◀"
+        style="@style/widget_metro_control_button_style"/>

calculatorpp/res/layout/widget_like_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<ImageButton xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/likeButton"
+        a:src="@drawable/kb_facebook"
+        style="@style/widget_metro_control_image_button_style"
+        a:contentDescription="Like"/>

calculatorpp/res/layout/widget_multiplication_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/multiplicationButton"
+        a:text="×"
+        style="@style/widget_metro_blue_operation_button_style"/>

calculatorpp/res/layout/widget_nine_digit_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/nineDigitButton"
+        a:text="9"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_one_digit_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/oneDigitButton"
+        a:text="1"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_paste_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<ImageButton xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/pasteButton"
+        a:src="@drawable/kb_paste"
+        style="@style/widget_metro_control_image_button_style"
+        a:contentDescription="Paste"/>

calculatorpp/res/layout/widget_percent_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/percentButton"
+        a:text="%"
+        style="@style/widget_metro_blue_operation_button_style"/>

calculatorpp/res/layout/widget_plus_button.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/plusButton"
+        a:text="+"
+        style="@style/widget_metro_blue_operation_button_style"/>

calculatorpp/res/layout/widget_power_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/powerButton"
+        a:text="^"
+        style="@style/widget_metro_blue_operation_button_style"/>

calculatorpp/res/layout/widget_right_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/rightButton"
+        a:text="▶"
+        style="@style/widget_metro_control_button_style"/>

calculatorpp/res/layout/widget_round_brackets_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/roundBracketsButton"
+        a:text="()"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_settings_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<ImageButton xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/settingsButton"
+        a:src="@drawable/kb_settings"
+        style="@style/widget_metro_control_image_button_style"
+        a:contentDescription="Settings"/>

calculatorpp/res/layout/widget_seven_digit_button.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/sevenDigitButton"
+        a:text="7"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_six_digit_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/sixDigitButton"
+        a:text="6"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_subtraction_button.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/subtractionButton"
+        a:text="-"
+        style="@style/widget_metro_blue_operation_button_style"/>

calculatorpp/res/layout/widget_three_digit_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/threeDigitButton"
+        a:text="3"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_two_digit_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/twoDigitButton"
+        a:text="2"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/layout/widget_vars_button.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/varsButton"
+        a:text="π,…"
+        a:textStyle="italic"
+        style="@style/widget_metro_control_button_style"/>

calculatorpp/res/layout/widget_zero_digit_button.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<Button xmlns:a="http://schemas.android.com/apk/res/android"
+        a:id="@+id/zeroDigitButton"
+        a:text="0"
+        style="@style/widget_metro_digit_button_style"/>

calculatorpp/res/values/colors.xml

@@ -11,6 +11,7 @@
 	<color name="button_ce_text_color">#ffffffff</color>
 	<color name="default_text_color">#ffffffff</color>
 	<color name="display_error_text_color">#ff393939</color>
+	<color name="widget_cursor_color">#ff707070</color>
 	<color name="selected_angle_unit_text_color">#ffffff99</color>
 	<color name="default_background">#ff000000</color>
 	<color name="pane_background">#ff1f1f1f</color>

calculatorpp/res/values/dimens.xml

@@ -15,6 +15,10 @@
     <dimen name="math_entity_text_size">20sp</dimen>
     <dimen name="math_entity_description_text_size">15sp</dimen>
 
+    <dimen name="widget_editor_text_size">25sp</dimen>
+    <dimen name="widget_keyboard_button_text_size">20dp</dimen>
+    <dimen name="widget_display_text_size">25sp</dimen>
+
     <!--only for not multipane-->
     <dimen name="editor_padding">5dp</dimen>
     <dimen name="display_padding">3dp</dimen>

calculatorpp/res/values/styles.xml

@@ -58,6 +58,14 @@
         <item name="android:textSize">@dimen/display_text_size</item>
     </style>
 
+    <style name="widget_editor_style" parent="editor_style">
+        <item name="android:textSize">@dimen/widget_editor_text_size</item>
+    </style>
+
+    <style name="widget_display_style" parent="display_style">
+        <item name="android:textSize">@dimen/widget_display_text_size</item>
+    </style>
+
     <style name="about_style" parent="default_text">
         <item name="android:gravity">center</item>
         <item name="android:layout_width">fill_parent</item>

calculatorpp/res/values/theme_default.xml

@@ -80,6 +80,10 @@
         <item name="android:layout_width">match_parent</item>
     </style>
 
+    <style name="widget_main_layout_style" parent="default_main_layout_style">
+        <item name="android:padding">1dp</item>
+    </style>
+
     <style name="default_actionbar_style" parent="@style/Widget.Sherlock.ActionBar">
         <item name="background">@drawable/default_abs__ab_transparent_dark_holo</item>
         <item name="android:background">@drawable/default_abs__ab_transparent_dark_holo</item>

calculatorpp/res/values/theme_metro_blue.xml

@@ -4,18 +4,34 @@
 		<item name="android:background">@drawable/metro_button_dark</item>
 	</style>
 
+    <style name="widget_metro_digit_button_style" parent="metro_digit_button_style">
+        <item name="android:textSize">@dimen/widget_keyboard_button_text_size</item>
+    </style>
+
 	<style name="metro_control_button_style" parent="metro_digit_button_style">
 		<item name="android:background">@drawable/metro_button_light</item>
 	</style>
 
+    <style name="widget_metro_control_button_style" parent="metro_control_button_style">
+        <item name="android:textSize">@dimen/widget_keyboard_button_text_size</item>
+    </style>
+
 	<style name="metro_blue_operation_button_style" parent="metro_digit_button_style">
 		<item name="android:background">@drawable/metro_blue_button</item>
 	</style>
 
+    <style name="widget_metro_blue_operation_button_style" parent="metro_blue_operation_button_style">
+        <item name="android:textSize">@dimen/widget_keyboard_button_text_size</item>
+    </style>
+
 	<style name="metro_control_image_button_style" parent="metro_control_button_style">
 		<item name="android:padding">6dp</item>
 	</style>
 
+    <style name="widget_metro_control_image_button_style" parent="metro_control_image_button_style">
+        <item name="android:scaleType">center</item>
+    </style>
+
     <style name="metro_blue_fragment_list_view_item_style" parent="default_fragment_list_view_item_style">
         <item name="background">@drawable/metro_blue_list_item</item>
         <item name="android:background">@drawable/metro_blue_list_item</item>

calculatorpp/res/values/theme_metro_green.xml

@@ -1,34 +1,17 @@
 <resources>
 
-	<style name="metro_digit_button_style" parent="keyboard_button_style">
-		<item name="android:background">@drawable/metro_button_dark</item>
-	</style>
-
-	<style name="metro_control_button_style" parent="metro_digit_button_style">
-		<item name="android:background">@drawable/metro_button_light</item>
-	</style>
-
 	<style name="metro_green_operation_button_style" parent="metro_digit_button_style">
 		<item name="android:background">@drawable/metro_button_green</item>
 	</style>
 
-	<style name="metro_control_image_button_style" parent="metro_control_button_style">
-		<item name="android:padding">6dp</item>
-	</style>
-
     <style name="metro_green_fragment_list_view_item_style" parent="default_fragment_list_view_item_style">
         <item name="background">@drawable/metro_green_list_item</item>
         <item name="android:background">@drawable/metro_green_list_item</item>
     </style>
 
-    <style name="metro_green_theme" parent="default_theme">
+    <style name="metro_green_theme" parent="metro_blue_theme">
-		<item name="digitButtonStyle">@style/metro_digit_button_style</item>
-		<item name="controlButtonStyle">@style/metro_control_button_style</item>
-		<item name="controlImageButtonStyle">@style/metro_control_image_button_style</item>
 		<item name="operationButtonStyle">@style/metro_green_operation_button_style</item>
-
         <item name="fragmentListViewItemStyle">@style/metro_green_fragment_list_view_item_style</item>
-
     </style>
 
 </resources>

calculatorpp/res/values/theme_metro_purple.xml

@@ -1,34 +1,18 @@
 <resources>
 
-	<style name="metro_digit_button_style" parent="keyboard_button_style">
-		<item name="android:background">@drawable/metro_button_dark</item>
-	</style>
-
-	<style name="metro_control_button_style" parent="metro_digit_button_style">
-		<item name="android:background">@drawable/metro_button_light</item>
-	</style>
-
 	<style name="metro_purple_operation_button_style" parent="metro_digit_button_style">
 		<item name="android:background">@drawable/metro_button_purple</item>
 	</style>
 
-	<style name="metro_control_image_button_style" parent="metro_control_button_style">
-		<item name="android:padding">6dp</item>
-	</style>
 
     <style name="metro_purple_fragment_list_view_item_style" parent="default_fragment_list_view_item_style">
         <item name="background">@drawable/metro_purple_list_item</item>
         <item name="android:background">@drawable/metro_purple_list_item</item>
     </style>
 
-	<style name="metro_purple_theme" parent="default_theme">
+	<style name="metro_purple_theme" parent="metro_blue_theme">
-		<item name="digitButtonStyle">@style/metro_digit_button_style</item>
-		<item name="controlButtonStyle">@style/metro_control_button_style</item>
-		<item name="controlImageButtonStyle">@style/metro_control_image_button_style</item>
 		<item name="operationButtonStyle">@style/metro_purple_operation_button_style</item>
-
         <item name="fragmentListViewItemStyle">@style/metro_purple_fragment_list_view_item_style</item>
-
     </style>
 
 </resources>

calculatorpp/res/xml/calculator_widget_info.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<appwidget-provider xmlns:a="http://schemas.android.com/apk/res/android"
+                    a:minWidth="180dp"
+                    a:minHeight="220dp"
+                    a:initialLayout="@layout/widget_layout"
+                    a:previewImage="@drawable/widget_preview"
+                    a:resizeMode="horizontal|vertical">
+
+</appwidget-provider>

calculatorpp/src/main/java/org/solovyev/android/AndroidUtils2.java

@@ -1,5 +1,6 @@
 package org.solovyev.android;
 
+import android.os.Looper;
 import android.support.v4.app.DialogFragment;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentManager;
@@ -32,4 +33,8 @@ public final class AndroidUtils2 {
         dialogFragment.show(ft, fragmentTag);
 
     }
+
+    public static boolean isUiThread() {
+        return Looper.myLooper() == Looper.getMainLooper();
+    }
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/AbstractCalculatorHelper.java

@@ -90,7 +90,7 @@ public abstract class AbstractCalculatorHelper implements SharedPreferences.OnSh
                 @Override
                 public boolean processDragEvent(@NotNull DragDirection dragDirection, @NotNull DragButton dragButton, @NotNull Point2d startPoint2d, @NotNull MotionEvent motionEvent) {
                     if (dragDirection == DragDirection.down) {
-                        CalculatorActivity.operatorsButtonClickHandler(activity);
+                        CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.show_operators, null);
                         return true;
                     }
                     return false;

calculatorpp/src/main/java/org/solovyev/android/calculator/AndroidCalculator.java

@@ -21,11 +21,15 @@ import java.util.List;
  * Date: 9/22/12
  * Time: 5:42 PM
  */
-public class AndroidCalculator implements Calculator {
+public class AndroidCalculator implements Calculator, CalculatorEventListener {
 
     @NotNull
     private final Calculator calculator = new CalculatorImpl();
 
+    public AndroidCalculator() {
+        this.calculator.addCalculatorEventListener(this);
+    }
+
     public static void showEvaluationError(@NotNull Context context, @NotNull final String errorMessage) {
         final LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
 
@@ -170,4 +174,45 @@ public class AndroidCalculator implements Calculator {
         calculator.simplify();
     }
 
+    @Override
+    public void onCalculatorEvent(@NotNull CalculatorEventData calculatorEventData, @NotNull CalculatorEventType calculatorEventType, @Nullable Object data) {
+        switch (calculatorEventType) {
+            case show_history:
+                CalculatorActivityLauncher.showHistory(CalculatorApplication.getInstance());
+                break;
+            case show_history_detached:
+                CalculatorActivityLauncher.showHistory(CalculatorApplication.getInstance(), true);
+                break;
+            case show_functions:
+                CalculatorActivityLauncher.showFunctions(CalculatorApplication.getInstance());
+                break;
+            case show_functions_detached:
+                CalculatorActivityLauncher.showFunctions(CalculatorApplication.getInstance(), true);
+                break;
+            case show_operators:
+                CalculatorActivityLauncher.showOperators(CalculatorApplication.getInstance());
+                break;
+            case show_operators_detached:
+                CalculatorActivityLauncher.showOperators(CalculatorApplication.getInstance(), true);
+                break;
+            case show_vars:
+                CalculatorActivityLauncher.showVars(CalculatorApplication.getInstance());
+                break;
+            case show_vars_detached:
+                CalculatorActivityLauncher.showVars(CalculatorApplication.getInstance(), true);
+                break;
+            case show_settings:
+                CalculatorActivityLauncher.showSettings(CalculatorApplication.getInstance());
+                break;
+            case show_settings_detached:
+                CalculatorActivityLauncher.showSettings(CalculatorApplication.getInstance(), true);
+                break;
+            case show_like_dialog:
+                CalculatorActivityLauncher.likeButtonPressed(CalculatorApplication.getInstance());
+                break;
+            case open_app:
+                CalculatorActivityLauncher.openApp(CalculatorApplication.getInstance());
+                break;
+        }
+    }
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/AndroidCalculatorEditorView.java

@@ -47,9 +47,8 @@ public class AndroidCalculatorEditorView extends EditText implements SharedPrefe
 
     private volatile boolean viewStateChange = false;
 
-    // NOTE: static because super constructor calls some overridden methods (like onSelectionChanged and current lock is not yet created)
+    @Nullable
-    @NotNull
+    private final Object viewLock = new Object();
-    private static final Object viewLock = new Object();
 
     @NotNull
     private final Handler uiHandler = new Handler();
@@ -154,45 +153,51 @@ public class AndroidCalculatorEditorView extends EditText implements SharedPrefe
 
     @Override
     public void setState(@NotNull final CalculatorEditorViewState viewState) {
-        synchronized (viewLock) {
+        if (viewLock != null) {
+            synchronized (viewLock) {
 
-            final CharSequence text = prepareText(viewState.getText(), highlightText);
+                final CharSequence text = prepareText(viewState.getText(), highlightText);
 
-            uiHandler.post(new Runnable() {
+                uiHandler.post(new Runnable() {
-                @Override
+                    @Override
-                public void run() {
+                    public void run() {
-                    final AndroidCalculatorEditorView editorView = AndroidCalculatorEditorView.this;
+                        final AndroidCalculatorEditorView editorView = AndroidCalculatorEditorView.this;
-                    synchronized (viewLock) {
+                        synchronized (viewLock) {
-                        try {
+                            try {
-                            editorView.viewStateChange = true;
+                                editorView.viewStateChange = true;
-                            editorView.viewState = viewState;
+                                editorView.viewState = viewState;
-                            editorView.setText(text, BufferType.EDITABLE);
+                                editorView.setText(text, BufferType.EDITABLE);
-                            editorView.setSelection(viewState.getSelection());
+                                editorView.setSelection(viewState.getSelection());
-                        } finally {
+                            } finally {
-                            editorView.viewStateChange = false;
+                                editorView.viewStateChange = false;
+                            }
                         }
                     }
-                }
+                });
-            });
+            }
         }
     }
 
     @Override
     protected void onSelectionChanged(int selStart, int selEnd) {
-        synchronized (viewLock) {
+        if (viewLock != null) {
-            if (!viewStateChange) {
+            synchronized (viewLock) {
-                // external text change => need to notify editor
+                if (!viewStateChange) {
-                super.onSelectionChanged(selStart, selEnd);
+                    // external text change => need to notify editor
-                CalculatorLocatorImpl.getInstance().getEditor().setSelection(selStart);
+                    super.onSelectionChanged(selStart, selEnd);
+                    CalculatorLocatorImpl.getInstance().getEditor().setSelection(selStart);
+                }
             }
         }
     }
 
     public void handleTextChange(Editable s) {
-        synchronized (viewLock) {
+        if (viewLock != null) {
-            if (!viewStateChange) {
+            synchronized (viewLock) {
-                // external text change => need to notify editor
+                if (!viewStateChange) {
-                CalculatorLocatorImpl.getInstance().getEditor().setText(String.valueOf(s));
+                    // external text change => need to notify editor
+                    CalculatorLocatorImpl.getInstance().getEditor().setText(String.valueOf(s));
+                }
             }
         }
     }

calculatorpp/src/main/java/org/solovyev/android/calculator/AndroidCalculatorNotifier.java

@@ -1,9 +1,11 @@
 package org.solovyev.android.calculator;
 
 import android.app.Application;
+import android.os.Handler;
 import android.widget.Toast;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.solovyev.android.AndroidUtils2;
 import org.solovyev.android.msg.AndroidMessage;
 import org.solovyev.common.msg.Message;
 import org.solovyev.common.msg.MessageType;
@@ -20,13 +22,18 @@ public class AndroidCalculatorNotifier implements CalculatorNotifier {
     @NotNull
     private final Application application;
 
+    @NotNull
+    private final Handler uiHandler = new Handler();
+
     public AndroidCalculatorNotifier(@NotNull Application application) {
+        assert AndroidUtils2.isUiThread();
+
         this.application = application;
     }
 
     @Override
     public void showMessage(@NotNull Message message) {
-        Toast.makeText(application, message.getLocalizedMessage(), Toast.LENGTH_SHORT).show();
+        showMessageInUiThread(message.getLocalizedMessage());
     }
 
     @Override
@@ -38,4 +45,25 @@ public class AndroidCalculatorNotifier implements CalculatorNotifier {
     public void showMessage(@NotNull Integer messageCode, @NotNull MessageType messageType, @Nullable Object... parameters) {
         showMessage(new AndroidMessage(messageCode, messageType, application, parameters));
     }
+
+    @Override
+    public void showDebugMessage(@Nullable final String tag, @NotNull final String message) {
+        /*if (AndroidUtils.isDebuggable(application)) {
+            showMessageInUiThread(tag == null ? message : tag + ": " + message);
+        }*/
+    }
+
+    private void showMessageInUiThread(@NotNull final String message) {
+        if (AndroidUtils2.isUiThread()) {
+            Toast.makeText(application, message, Toast.LENGTH_SHORT).show();
+        } else {
+            uiHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    Toast.makeText(application,message, Toast.LENGTH_SHORT).show();
+                }
+            });
+        }
+    }
+
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java

@@ -5,7 +5,6 @@
 
 package org.solovyev.android.calculator;
 
-import android.app.Activity;
 import android.app.AlertDialog;
 import android.content.Context;
 import android.content.SharedPreferences;
@@ -18,6 +17,7 @@ import android.util.Log;
 import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.View;
+import android.widget.Button;
 import android.widget.TextView;
 import com.actionbarsherlock.app.SherlockFragmentActivity;
 import org.jetbrains.annotations.NotNull;
@@ -167,7 +167,7 @@ public class CalculatorActivity extends SherlockFragmentActivity implements Shar
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void equalsButtonClickHandler(@NotNull View v) {
-        getCalculator().evaluate();
+        buttonPressed(CalculatorSpecialButton.equals);
     }
 
     @Override
@@ -241,12 +241,12 @@ public class CalculatorActivity extends SherlockFragmentActivity implements Shar
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void historyButtonClickHandler(@NotNull View v) {
-        CalculatorActivityLauncher.showHistory(this);
+        buttonPressed(CalculatorSpecialButton.history);
     }
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void eraseButtonClickHandler(@NotNull View v) {
-        CalculatorLocatorImpl.getInstance().getEditor().erase();
+        buttonPressed(CalculatorSpecialButton.erase);
     }
 
     @SuppressWarnings({"UnusedDeclaration"})
@@ -254,24 +254,14 @@ public class CalculatorActivity extends SherlockFragmentActivity implements Shar
         throw new UnsupportedOperationException("Not implemented yet!");
     }
 
-    @SuppressWarnings({"UnusedDeclaration"})
-    public void moveLeftButtonClickHandler(@NotNull View v) {
-        getKeyboard().moveCursorLeft();
-    }
-
-    @SuppressWarnings({"UnusedDeclaration"})
-    public void moveRightButtonClickHandler(@NotNull View v) {
-        getKeyboard().moveCursorRight();
-    }
-
     @SuppressWarnings({"UnusedDeclaration"})
     public void pasteButtonClickHandler(@NotNull View v) {
-        getKeyboard().pasteButtonPressed();
+        buttonPressed(CalculatorSpecialButton.paste);
     }
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void copyButtonClickHandler(@NotNull View v) {
-        getKeyboard().copyButtonPressed();
+        buttonPressed(CalculatorSpecialButton.copy);
     }
 
     @NotNull
@@ -281,39 +271,52 @@ public class CalculatorActivity extends SherlockFragmentActivity implements Shar
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void clearButtonClickHandler(@NotNull View v) {
-        getKeyboard().clearButtonPressed();
+        buttonPressed(CalculatorSpecialButton.clear);
     }
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void digitButtonClickHandler(@NotNull View v) {
         Log.d(String.valueOf(v.getId()), "digitButtonClickHandler() for: " + v.getId() + ". Pressed: " + v.isPressed());
-        if (((ColorButton) v).isShowText()) {
+
-            getKeyboard().digitButtonPressed(((ColorButton) v).getText().toString());
+        if (v instanceof Button) {
+
+            boolean processText = true;
+            if ( v instanceof ColorButton) {
+                processText = ((ColorButton) v).isShowText();
+            }
+
+            if ( processText ) {
+                buttonPressed(((Button)v).getText().toString());
+            }
         }
     }
 
+    private void buttonPressed(@NotNull CalculatorSpecialButton button) {
+        buttonPressed(button.getActionCode());
+    }
+
+    private void buttonPressed(@NotNull String text) {
+        getKeyboard().buttonPressed(text);
+    }
+
     @SuppressWarnings({"UnusedDeclaration"})
     public void functionsButtonClickHandler(@NotNull View v) {
-        CalculatorActivityLauncher.showFunctions(this);
+        buttonPressed(CalculatorSpecialButton.functions);
     }
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void operatorsButtonClickHandler(@NotNull View v) {
-        CalculatorActivityLauncher.showOperators(this);
+        buttonPressed(CalculatorSpecialButton.operators);
-    }
-
-    public static void operatorsButtonClickHandler(@NotNull Activity activity) {
-        CalculatorActivityLauncher.showOperators(activity);
     }
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void varsButtonClickHandler(@NotNull View v) {
-        CalculatorActivityLauncher.showVars(this);
+        buttonPressed(CalculatorSpecialButton.vars);
     }
 
     @SuppressWarnings({"UnusedDeclaration"})
     public void likeButtonClickHandler(@NotNull View v) {
-        CalculatorApplication.likeButtonPressed(this);
+        buttonPressed(CalculatorSpecialButton.like);
     }
 
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/CalculatorActivityLauncher.java

@@ -2,6 +2,7 @@ package org.solovyev.android.calculator;
 
 import android.content.Context;
 import android.content.Intent;
+import android.net.Uri;
 import com.actionbarsherlock.app.SherlockFragmentActivity;
 import jscl.math.Generic;
 import jscl.math.function.Constant;
@@ -24,7 +25,13 @@ import org.solovyev.common.text.StringUtils;
 public class CalculatorActivityLauncher {
 
 	public static void showHistory(@NotNull final Context context) {
-		context.startActivity(new Intent(context, CalculatorHistoryActivity.class));
+        showHistory(context, false);
+    }
+
+	public static void showHistory(@NotNull final Context context, boolean detached) {
+        final Intent intent = new Intent(context, CalculatorHistoryActivity.class);
+        addFlags(intent, detached);
+        context.startActivity(intent);
 	}
 
 	public static void showHelp(@NotNull final Context context) {
@@ -32,23 +39,57 @@ public class CalculatorActivityLauncher {
 	}
 
 	public static void showSettings(@NotNull final Context context) {
-		context.startActivity(new Intent(context, CalculatorPreferencesActivity.class));
+        showSettings(context, false);
+    }
+	public static void showSettings(@NotNull final Context context, boolean detached) {
+        final Intent intent = new Intent(context, CalculatorPreferencesActivity.class);
+        addFlags(intent, detached);
+        context.startActivity(intent);
 	}
 
-	public static void showAbout(@NotNull final Context context) {
+    private static void addFlags(@NotNull Intent intent, boolean detached) {
+        int flags = Intent.FLAG_ACTIVITY_NEW_TASK;
+
+        if (detached) {
+            flags = flags | Intent.FLAG_ACTIVITY_NO_HISTORY;
+        }
+
+        intent.setFlags(flags);
+
+    }
+
+    public static void showAbout(@NotNull final Context context) {
 		context.startActivity(new Intent(context, CalculatorAboutActivity.class));
 	}
 
 	public static void showFunctions(@NotNull final Context context) {
-		context.startActivity(new Intent(context, CalculatorFunctionsActivity.class));
+        showHistory(context, false);
+    }
+
+	public static void showFunctions(@NotNull final Context context, boolean detached) {
+        final Intent intent = new Intent(context, CalculatorFunctionsActivity.class);
+        addFlags(intent, detached);
+        context.startActivity(intent);
 	}
 
 	public static void showOperators(@NotNull final Context context) {
-		context.startActivity(new Intent(context, CalculatorOperatorsActivity.class));
+        showOperators(context, false);
+    }
+
+	public static void showOperators(@NotNull final Context context, boolean detached) {
+        final Intent intent = new Intent(context, CalculatorOperatorsActivity.class);
+        addFlags(intent, detached);
+        context.startActivity(intent);
 	}
 
 	public static void showVars(@NotNull final Context context) {
-		context.startActivity(new Intent(context, CalculatorVarsActivity.class));
+        showVars(context, false);
+    }
+
+    public static void showVars(@NotNull final Context context, boolean detached) {
+        final Intent intent = new Intent(context, CalculatorVarsActivity.class);
+        addFlags(intent, detached);
+        context.startActivity(intent);
 	}
 
 	public static void plotGraph(@NotNull final Context context, @NotNull Generic generic, @NotNull Constant constant){
@@ -82,4 +123,16 @@ public class CalculatorActivityLauncher {
             CalculatorLocatorImpl.getInstance().getNotifier().showMessage(R.string.c_not_valid_result, MessageType.error);
 		}
 	}
+
+    public static void openApp(@NotNull Context context) {
+        final Intent intent = new Intent(context, CalculatorActivity.class);
+        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TOP);
+        context.startActivity(intent);
+    }
+
+    public static void likeButtonPressed(@NotNull final Context context) {
+        final Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(CalculatorApplication.FACEBOOK_APP_URL));
+        addFlags(intent, false);
+        context.startActivity(intent);
+    }
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/CalculatorApplication.java

@@ -1,9 +1,6 @@
 package org.solovyev.android.calculator;
 
-import android.content.Context;
-import android.content.Intent;
 import android.content.SharedPreferences;
-import android.net.Uri;
 import android.preference.PreferenceManager;
 import net.robotmedia.billing.BillingController;
 import net.robotmedia.billing.helper.DefaultBillingObserver;
@@ -15,6 +12,7 @@ import org.jetbrains.annotations.NotNull;
 import org.solovyev.android.ads.AdsController;
 import org.solovyev.android.calculator.history.AndroidCalculatorHistory;
 import org.solovyev.android.calculator.model.AndroidCalculatorEngine;
+import org.solovyev.android.calculator.widget.CalculatorWidgetHelper;
 
 /**
  * User: serso
@@ -39,6 +37,7 @@ public class CalculatorApplication extends android.app.Application {
     **********************************************************************
     */
 
+    private static final String TAG = "Calculator++ Application";
     public static final String FACEBOOK_APP_URL = "http://www.facebook.com/calculatorpp";
 
     public static final String AD_FREE_PRODUCT_ID = "ad_free";
@@ -49,6 +48,9 @@ public class CalculatorApplication extends android.app.Application {
     @NotNull
     private static CalculatorApplication instance;
 
+    @NotNull
+    private CalculatorWidgetHelper widgetHelper;
+
     /*
     **********************************************************************
     *
@@ -91,6 +93,10 @@ public class CalculatorApplication extends android.app.Application {
 
         CalculatorLocatorImpl.getInstance().getCalculator().init();
 
+        // in order to not to be garbage collected
+        widgetHelper = new CalculatorWidgetHelper();
+        CalculatorLocatorImpl.getInstance().getCalculator().addCalculatorEventListener(widgetHelper);
+
         AdsController.getInstance().init(ADMOB_USER_ID, AD_FREE_PRODUCT_ID, new BillingController.IConfiguration() {
 
             @Override
@@ -115,6 +121,9 @@ public class CalculatorApplication extends android.app.Application {
                 AdsController.getInstance().isAdFree(CalculatorApplication.this);
             }
         }).start();
+
+        CalculatorLocatorImpl.getInstance().getLogger().debug(TAG, "Application started!");
+        CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "Application started!");
     }
 
     private void setTheme(@NotNull SharedPreferences preferences) {
@@ -154,7 +163,4 @@ public class CalculatorApplication extends android.app.Application {
         return instance;
     }
 
-    public static void likeButtonPressed(@NotNull final Context context) {
-        context.startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(FACEBOOK_APP_URL)));
-    }
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/DigitButtonDragProcessor.java

@@ -7,10 +7,10 @@ package org.solovyev.android.calculator;
 
 import android.view.MotionEvent;
 import org.jetbrains.annotations.NotNull;
-import org.solovyev.android.view.drag.DragDirection;
-import org.solovyev.android.view.drag.SimpleOnDragListener;
 import org.solovyev.android.view.drag.DirectionDragButton;
 import org.solovyev.android.view.drag.DragButton;
+import org.solovyev.android.view.drag.DragDirection;
+import org.solovyev.android.view.drag.SimpleOnDragListener;
 import org.solovyev.common.math.Point2d;
 
 /**
@@ -30,7 +30,7 @@ public class DigitButtonDragProcessor implements SimpleOnDragListener.DragProces
 	@Override
 	public boolean processDragEvent(@NotNull DragDirection dragDirection, @NotNull DragButton dragButton, @NotNull Point2d startPoint2d, @NotNull MotionEvent motionEvent) {
 		assert dragButton instanceof DirectionDragButton;
-        calculatorKeyboard.digitButtonPressed(((DirectionDragButton) dragButton).getText(dragDirection));
+        calculatorKeyboard.buttonPressed(((DirectionDragButton) dragButton).getText(dragDirection));
 		return true;
 	}
 

calculatorpp/src/main/java/org/solovyev/android/calculator/view/NumeralBaseConverterDialog.java

@@ -71,7 +71,7 @@ public class NumeralBaseConverterDialog {
                     toUnitsValue = ((CalculatorNumeralBase) toUnits.getUnitType()).getNumeralBase().getJsclPrefix() + toUnitsValue;
                 }
 
-                CalculatorLocatorImpl.getInstance().getKeyboard().digitButtonPressed(toUnitsValue);
+                CalculatorLocatorImpl.getInstance().getKeyboard().buttonPressed(toUnitsValue);
                 final AlertDialog alertDialog = alertDialogHolder.getObject();
                 if (alertDialog != null) {
                     alertDialog.dismiss();

calculatorpp/src/main/java/org/solovyev/android/calculator/widget/CalculatorWidgetConfigurationActivity.java

@@ -0,0 +1,11 @@
+package org.solovyev.android.calculator.widget;
+
+import android.app.Activity;
+
+/**
+ * User: Solovyev_S
+ * Date: 19.10.12
+ * Time: 16:20
+ */
+public class CalculatorWidgetConfigurationActivity extends Activity {
+}

calculatorpp/src/main/java/org/solovyev/android/calculator/widget/CalculatorWidgetHelper.java

@@ -0,0 +1,65 @@
+package org.solovyev.android.calculator.widget;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.android.calculator.*;
+
+/**
+ * User: serso
+ * Date: 10/19/12
+ * Time: 11:11 PM
+ */
+public class CalculatorWidgetHelper extends BroadcastReceiver implements CalculatorEventListener {
+
+    private static final String TAG = "Calculator++ Widget Helper";
+
+    @NotNull
+    private final CalculatorEventHolder lastEvent = new CalculatorEventHolder(CalculatorUtils.createFirstEventDataId());
+
+    public CalculatorWidgetHelper() {
+        CalculatorLocatorImpl.getInstance().getCalculator().addCalculatorEventListener(this);
+    }
+
+    @Override
+    public void onCalculatorEvent(@NotNull CalculatorEventData calculatorEventData, @NotNull CalculatorEventType calculatorEventType, @Nullable Object data) {
+        final CalculatorEventHolder.Result result = lastEvent.apply(calculatorEventData);
+        if (result.isNewAfter()) {
+            switch (calculatorEventType) {
+                case editor_state_changed_light:
+                case editor_state_changed:
+                    final CalculatorEditorChangeEventData editorChangeData = (CalculatorEditorChangeEventData) data;
+                    final CalculatorEditorViewState newEditorState = editorChangeData.getNewValue();
+
+                    CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "Editor state changed: " + newEditorState.getText());
+
+                    CalculatorWidgetProvider.onEditorStateChanged(CalculatorApplication.getInstance(), newEditorState);
+                    break;
+
+                case display_state_changed:
+                    final CalculatorDisplayChangeEventData displayChangeData = (CalculatorDisplayChangeEventData) data;
+                    final CalculatorDisplayViewState newDisplayState = displayChangeData.getNewValue();
+
+                    CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "Display state changed: " + newDisplayState.getText());
+
+                    CalculatorWidgetProvider.onDisplayStateChanged(CalculatorApplication.getInstance(), newDisplayState);
+                    break;
+            }
+        }
+    }
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        if (CalculatorWidgetProvider.BUTTON_PRESSED_ACTION.equals(intent.getAction())) {
+            final int buttonId = intent.getIntExtra(CalculatorWidgetProvider.BUTTON_ID_EXTRA, 0);
+            //Toast.makeText(context, "Button id: " + buttonId, Toast.LENGTH_SHORT).show();
+
+            final WidgetButton button = WidgetButton.getById(buttonId);
+            if ( button != null ) {
+                button.onClick(context);
+            }
+        }
+    }
+}

calculatorpp/src/main/java/org/solovyev/android/calculator/widget/CalculatorWidgetProvider.java

@@ -0,0 +1,199 @@
+package org.solovyev.android.calculator.widget;
+
+import android.app.PendingIntent;
+import android.appwidget.AppWidgetManager;
+import android.appwidget.AppWidgetProvider;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.text.Html;
+import android.widget.RemoteViews;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.android.calculator.CalculatorDisplayViewState;
+import org.solovyev.android.calculator.CalculatorEditorViewState;
+import org.solovyev.android.calculator.CalculatorLocatorImpl;
+import org.solovyev.android.calculator.R;
+
+import java.io.Serializable;
+
+/**
+ * User: Solovyev_S
+ * Date: 19.10.12
+ * Time: 16:18
+ */
+public class CalculatorWidgetProvider extends AppWidgetProvider {
+
+    /*
+    **********************************************************************
+    *
+    *                           CONSTANTS
+    *
+    **********************************************************************
+    */
+    public static final String BUTTON_ID_EXTRA = "buttonId";
+    public static final String BUTTON_PRESSED_ACTION = "org.solovyev.calculator.widget.BUTTON_PRESSED";
+
+    private static final String EDITOR_STATE_CHANGED_ACTION = "org.solovyev.calculator.widget.EDITOR_STATE_CHANGED";
+    private static final String EDITOR_STATE_EXTRA = "editorState";
+
+    private static final String DISPLAY_STATE_CHANGED_ACTION = "org.solovyev.calculator.widget.DISPLAY_STATE_CHANGED";
+    private static final String DISPLAY_STATE_EXTRA = "displayState";
+
+    private static final String TAG = "Calculator++ Widget";
+
+    /*
+    **********************************************************************
+    *
+    *                           FIELDS
+    *
+    **********************************************************************
+    */
+
+    @Nullable
+    private String cursorColor;
+
+    /*
+    **********************************************************************
+    *
+    *                           METHODS
+    *
+    **********************************************************************
+    */
+
+    @Override
+    public void onEnabled(Context context) {
+        super.onEnabled(context);
+
+        getCursorColor(context);
+    }
+
+    @NotNull
+    private String getCursorColor(@NotNull Context context) {
+        if ( cursorColor == null ) {
+            cursorColor = Integer.toHexString(context.getResources().getColor(R.color.widget_cursor_color)).substring(2);
+        }
+        return cursorColor;
+    }
+
+    @Override
+    public void onUpdate(@NotNull Context context,
+                         @NotNull AppWidgetManager appWidgetManager,
+                         @NotNull int[] appWidgetIds) {
+        super.onUpdate(context, appWidgetManager, appWidgetIds);
+
+        for (int appWidgetId : appWidgetIds) {
+            final RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
+
+            for (WidgetButton button : WidgetButton.values()) {
+                final Intent onButtonClickIntent = new Intent(context, CalculatorWidgetProvider.class);
+                onButtonClickIntent.setAction(BUTTON_PRESSED_ACTION);
+                onButtonClickIntent.putExtra(BUTTON_ID_EXTRA, button.getButtonId());
+                final PendingIntent pendingIntent = PendingIntent.getBroadcast(context, button.getButtonId(), onButtonClickIntent, PendingIntent.FLAG_UPDATE_CURRENT);
+                if (pendingIntent != null) {
+                    views.setOnClickPendingIntent(button.getButtonId(), pendingIntent);
+                }
+            }
+
+            appWidgetManager.updateAppWidget(appWidgetId, views);
+        }
+    }
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        super.onReceive(context, intent);
+
+        if (CalculatorWidgetProvider.BUTTON_PRESSED_ACTION.equals(intent.getAction())) {
+            final int buttonId = intent.getIntExtra(CalculatorWidgetProvider.BUTTON_ID_EXTRA, 0);
+
+            final WidgetButton button = WidgetButton.getById(buttonId);
+            if (button != null) {
+                button.onClick(context);
+            }
+        } else if (EDITOR_STATE_CHANGED_ACTION.equals(intent.getAction())) {
+            CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "Editor state changed broadcast received!");
+
+            final Serializable object = intent.getSerializableExtra(EDITOR_STATE_EXTRA);
+            if (object instanceof CalculatorEditorViewState) {
+                updateEditorState(context, (CalculatorEditorViewState) object);
+            }
+        } else if (DISPLAY_STATE_CHANGED_ACTION.equals(intent.getAction())) {
+            CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "Display state changed broadcast received!");
+
+            final Serializable object = intent.getSerializableExtra(DISPLAY_STATE_EXTRA);
+            if (object instanceof CalculatorDisplayViewState) {
+                updateDisplayState(context, (CalculatorDisplayViewState) object);
+            }
+        }
+    }
+
+    private void updateDisplayState(@NotNull Context context, @NotNull CalculatorDisplayViewState displayState) {
+        if (displayState.isValid()) {
+            setText(context, R.id.calculatorDisplay, displayState.getText());
+            setTextColor(context, R.id.calculatorDisplay, context.getResources().getColor(R.color.default_text_color));
+        } else {
+            setTextColor(context, R.id.calculatorDisplay, context.getResources().getColor(R.color.display_error_text_color));
+        }
+    }
+
+    private void setText(@NotNull Context context, int textViewId, @Nullable CharSequence text) {
+        final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
+
+        final int[] appWidgetIds = appWidgetManager.getAppWidgetIds(new ComponentName(context, CalculatorWidgetProvider.class));
+        for (int appWidgetId : appWidgetIds) {
+            final RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
+            views.setTextViewText(textViewId, text);
+            appWidgetManager.updateAppWidget(appWidgetId, views);
+        }
+    }
+
+    private void setTextColor(@NotNull Context context, int textViewId, int textColor) {
+        final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
+
+        final int[] appWidgetIds = appWidgetManager.getAppWidgetIds(new ComponentName(context, CalculatorWidgetProvider.class));
+        for (int appWidgetId : appWidgetIds) {
+            final RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
+            views.setTextColor(textViewId, textColor);
+            appWidgetManager.updateAppWidget(appWidgetId, views);
+        }
+    }
+
+    private void updateEditorState(@NotNull Context context, @NotNull CalculatorEditorViewState editorState) {
+        String text = editorState.getText();
+
+        CharSequence newText = text;
+        int selection = editorState.getSelection();
+        if (selection >= 0 && selection <= text.length() ) {
+            // inject cursor
+            newText = Html.fromHtml(text.substring(0, selection) + "<font color=\"#" + getCursorColor(context) + "\">|</font>" + text.substring(selection));
+        }
+        CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "New editor state: " + text);
+        setText(context, R.id.calculatorEditor, newText);
+    }
+
+    /*
+    **********************************************************************
+    *
+    *                           STATIC
+    *
+    **********************************************************************
+    */
+
+    public static void onEditorStateChanged(@NotNull Context context, @NotNull CalculatorEditorViewState editorViewState) {
+        final Intent intent = new Intent(EDITOR_STATE_CHANGED_ACTION);
+        intent.setClass(context, CalculatorWidgetProvider.class);
+        intent.putExtra(EDITOR_STATE_EXTRA, editorViewState);
+        context.sendBroadcast(intent);
+        CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "Editor state changed broadcast sent");
+    }
+
+    public static void onDisplayStateChanged(@NotNull Context context, @NotNull CalculatorDisplayViewState displayViewState) {
+        final Intent intent = new Intent(DISPLAY_STATE_CHANGED_ACTION);
+        intent.setClass(context, CalculatorWidgetProvider.class);
+        intent.putExtra(DISPLAY_STATE_EXTRA, displayViewState);
+        context.sendBroadcast(intent);
+        CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage(TAG, "Display state changed broadcast sent");
+    }
+
+
+}

calculatorpp/src/main/java/org/solovyev/android/calculator/widget/WidgetButton.java

@@ -0,0 +1,94 @@
+package org.solovyev.android.calculator.widget;
+
+import android.content.Context;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.android.calculator.CalculatorLocatorImpl;
+import org.solovyev.android.calculator.CalculatorSpecialButton;
+import org.solovyev.android.calculator.R;
+
+/**
+* User: serso
+* Date: 10/20/12
+* Time: 12:05 AM
+*/
+enum WidgetButton {
+
+    /*digits*/
+    one(R.id.oneDigitButton, "1"),
+    two(R.id.twoDigitButton, "2"),
+    three(R.id.threeDigitButton, "3"),
+    four(R.id.fourDigitButton, "4"),
+    five(R.id.fiveDigitButton, "5"),
+    six(R.id.sixDigitButton, "6"),
+    seven(R.id.sevenDigitButton, "7"),
+    eight(R.id.eightDigitButton, "8"),
+    nine(R.id.nineDigitButton, "9"),
+    zero(R.id.zeroDigitButton, "0"),
+
+    period(R.id.periodButton, "."),
+    brackets(R.id.roundBracketsButton, "()"),
+
+    settings(R.id.settingsButton, CalculatorSpecialButton.settings_detached),
+    like(R.id.likeButton, CalculatorSpecialButton.like),
+
+    /*last row*/
+    left(R.id.leftButton, CalculatorSpecialButton.cursor_left),
+    right(R.id.rightButton, CalculatorSpecialButton.cursor_right),
+    vars(R.id.varsButton, CalculatorSpecialButton.vars_detached),
+    functions(R.id.functionsButton, CalculatorSpecialButton.functions_detached),
+    app(R.id.appButton, CalculatorSpecialButton.open_app),
+    history(R.id.historyButton, CalculatorSpecialButton.history_detached),
+
+    /*operations*/
+    multiplication(R.id.multiplicationButton, "*"),
+    division(R.id.divisionButton, "/"),
+    plus(R.id.plusButton, "+"),
+    subtraction(R.id.subtractionButton, "-"),
+    percent(R.id.percentButton, "%"),
+    power(R.id.powerButton, "^"),
+
+    /*last column*/
+    clear(R.id.clearButton, CalculatorSpecialButton.clear),
+    erase(R.id.eraseButton, CalculatorSpecialButton.erase),
+    copy(R.id.copyButton, CalculatorSpecialButton.copy),
+    paste(R.id.pasteButton, CalculatorSpecialButton.paste),
+
+    /*equals*/
+    equals(R.id.equalsButton, CalculatorSpecialButton.equals);
+
+
+    private final int buttonId;
+
+    @NotNull
+    private final String text;
+
+    WidgetButton(int buttonId, @NotNull CalculatorSpecialButton button) {
+        this(buttonId, button.getActionCode());
+    }
+
+    WidgetButton(int buttonId, @NotNull String text) {
+        this.buttonId = buttonId;
+        this.text = text;
+    }
+
+    public void onClick(@NotNull Context context) {
+        CalculatorLocatorImpl.getInstance().getNotifier().showDebugMessage("Calculator++ Widget", "Button pressed: " + text);
+        CalculatorLocatorImpl.getInstance().getKeyboard().buttonPressed(text);
+    }
+
+    @Nullable
+    public static WidgetButton getById(int buttonId) {
+        for (WidgetButton widgetButton : values()) {
+            if (widgetButton.buttonId == buttonId) {
+                return widgetButton;
+            }
+        }
+
+        return null;
+    }
+
+    public int getButtonId() {
+        return buttonId;
+    }
+}