changes

AndroidManifest.xml

@@ -9,19 +9,25 @@
 
 	<application a:icon="@drawable/icon" a:label="@string/c_app_name">
 
-		<activity a:name=".CalculatorActivity" a:label="@string/c_app_name">
+		<activity a:name=".CalculatorActivity"
+				  a:windowSoftInputMode="stateHidden"
+				  a:label="@string/c_app_name">
 			<intent-filter>
-                <action a:name="android.intent.action.MAIN" />
+				<action a:name="android.intent.action.MAIN"/>
-                <category a:name="android.intent.category.LAUNCHER" />
+				<category a:name="android.intent.category.LAUNCHER"/>
 				<action a:name="org.solovyev.android.calculator.CalculatorActivity.insertText"/>
 			</intent-filter>
 		</activity>
 
-		<activity a:name=".CalculatorPreferencesActivity" a:label="@string/c_app_settings"/>
+		<activity a:name=".CalculatorPreferencesActivity"
-		<activity a:name=".AboutActivity" a:label="@string/c_about"/>
+				  a:label="@string/c_app_settings"/>
+
+		<activity a:name=".AboutActivity"
+				  a:label="@string/c_about"/>
+
 		<activity a:name=".CalculatorVarsActivity"
 				  a:label="@string/c_vars_and_constants"
-					a:configChanges="orientation|keyboardHidden" />
+				  a:configChanges="orientation|keyboardHidden"/>
 
 	</application>
 </manifest>

res/layout-land/main.xml

@@ -17,73 +17,68 @@
 
 		<LinearLayout a:layout_weight="1" a:layout_width="match_parent" a:layout_height="0dp">
 
-			<org.solovyev.android.view.widgets.DirectionDragButton a:id="@+id/leftButton"
+			<include layout="@layout/calc_left_button"
-																   calc:textUp="↞"
+					 a:layout_width="match_parent"
-																   a:text="←"
+					 a:layout_height="match_parent"
-																   a:layout_weight="1.5"
+					 a:layout_weight="1.5"/>
-																   style="@style/control_button_style"
-																   a:onClick="moveLeftButtonClickHandler"/>
 
-			<org.solovyev.android.view.widgets.DirectionDragButton a:id="@+id/eraseButton"
+			<include layout="@layout/calc_erase_button"
-																   a:text="@string/c_erase"
+					 a:layout_width="match_parent"
-																   a:layout_weight="1.5"
+					 a:layout_height="match_parent"
-																   style="@style/control_button_style"
+					 a:layout_weight="1.5"/>
-																   a:onClick="eraseButtonClickHandler"/>
-
-			<include layout="@layout/calc_display"/>
 
 
-			<org.solovyev.android.view.widgets.DirectionDragButton a:id="@+id/clearButton"
+			<include layout="@layout/calc_display"
-																   a:text="@string/c_clear"
+					 a:layout_width="match_parent"
-																   a:layout_weight="1.5"
+					 a:layout_height="match_parent"
-																   style="@style/control_button_style"
+					 a:layout_weight="1"/>
-																   a:onClick="clearButtonClickHandler"/>
 
-			<org.solovyev.android.view.widgets.DirectionDragButton a:id="@+id/rightButton"
+			<include layout="@layout/calc_clear_button"
-																   calc:textUp="↠"
+					 a:layout_width="match_parent"
-																   a:text="→"
+					 a:layout_height="match_parent"
-																   a:layout_weight="1.5"
+					 a:layout_weight="1.5"/>
-																   style="@style/control_button_style"
-																   a:onClick="moveRightButtonClickHandler"/>
 
+			<include layout="@layout/calc_right_button"
+					 a:layout_width="match_parent"
+					 a:layout_height="match_parent"
+					 a:layout_weight="1.5"/>
 
 		</LinearLayout>
 
 		<LinearLayout a:layout_weight="1" a:layout_width="match_parent" a:layout_height="0dp">
 
+			<include layout="@layout/calc_equals_button"/>
+			<include layout="@layout/calc_paste_button"/>
 			<include layout="@layout/calc_one_digit_button"/>
 			<include layout="@layout/calc_two_digit_button"/>
 			<include layout="@layout/calc_three_digit_button"/>
 			<include layout="@layout/calc_multiplication_button"/>
 			<include layout="@layout/calc_division_button"/>
-			<include layout="@layout/calc_equals_button"/>
-			<include layout="@layout/calc_paste_button"/>
-
 
 		</LinearLayout>
 
 		<LinearLayout a:layout_weight="1" a:layout_width="match_parent" a:layout_height="0dp">
 
+			<include layout="@layout/calc_history_button"/>
+			<include layout="@layout/calc_copy_button"/>
 			<include layout="@layout/calc_four_digit_button"/>
 			<include layout="@layout/calc_five_digit_button"/>
 			<include layout="@layout/calc_six_digit_button"/>
 			<include layout="@layout/calc_plus_button"/>
 			<include layout="@layout/calc_subtraction_button"/>
-			<include layout="@layout/calc_square_brackets_button"/>
-			<include layout="@layout/calc_history_button"/>
 
 
 		</LinearLayout>
 
 		<LinearLayout a:layout_weight="1" a:layout_width="match_parent" a:layout_height="0dp">
 
+			<include layout="@layout/calc_vars_button"/>
+			<include layout="@layout/calc_square_brackets_button"/>
 			<include layout="@layout/calc_seven_digit_button"/>
 			<include layout="@layout/calc_eight_digit_button"/>
 			<include layout="@layout/calc_nine_digit_button"/>
 			<include layout="@layout/calc_zero_digit_button"/>
 			<include layout="@layout/calc_round_brackets_button"/>
-			<include layout="@layout/calc_vars_button"/>
-			<org.solovyev.android.view.widgets.DirectionDragButton a:text="" style="@style/control_button_style"/>
 
 
 		</LinearLayout>

res/layout-port/main.xml

@@ -17,15 +17,15 @@
 
 		<LinearLayout a:layout_weight="1" a:layout_width="match_parent" a:layout_height="0dp">
 
-			<org.solovyev.android.view.widgets.DirectionDragButton
+			<include layout="@layout/calc_equals_button"
-					xmlns:a="http://schemas.android.com/apk/res/android"
-					a:id="@+id/equalsButton"
-					a:text="="
 					 a:layout_weight="4"
-					style="@style/control_button_style"
+					 a:layout_height="match_parent"
-					a:onClick="numericButtonClickHandler"/>
+					 a:layout_width="match_parent" />
 
-			<include layout="@layout/calc_display"/>
+			<include layout="@layout/calc_display"
+					 a:layout_width="match_parent"
+					 a:layout_height="match_parent"
+					 a:layout_weight="1"/>
 
 		</LinearLayout>
 
@@ -65,7 +65,7 @@
 			<include layout="@layout/calc_zero_digit_button"/>
 			<include layout="@layout/calc_square_brackets_button"/>
 			<include layout="@layout/calc_subtraction_button"/>
-			<include layout="@layout/calc_history_button"/>
+			<include layout="@layout/calc_copy_button"/>
 
 		</LinearLayout>
 
@@ -75,11 +75,8 @@
 			<include layout="@layout/calc_left_button"/>
 			<include layout="@layout/calc_right_button"/>
 			<include layout="@layout/calc_vars_button"/>
-
+			<include layout="@layout/calc_donate_button"/>
-			<org.solovyev.android.view.widgets.DirectionDragButton a:text="" style="@style/control_button_style"/>
+			<include layout="@layout/calc_history_button"/>
-
-			<org.solovyev.android.view.widgets.DirectionDragButton a:text="" style="@style/control_button_style"/>
-
 
 		</LinearLayout>
 	</LinearLayout>

res/layout/calc_copy_button.xml

@@ -0,0 +1,15 @@
+<?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"
+			 xmlns:calc="http://schemas.android.com/apk/res/org.solovyev.android.calculator"
+			 a:id="@+id/pasteButton"
+			 a:src="@drawable/copy"
+			 style="@style/control_button_style"
+			 a:padding="6dp"
+			 a:onClick="copyButtonClickHandler"/>

res/layout/calc_display.xml

@@ -8,7 +8,7 @@
 
 <org.solovyev.android.calculator.CalculatorDisplay
 		xmlns:a="http://schemas.android.com/apk/res/android"
-		a:id="@+id/resultEditText"
+		a:id="@+id/calculatorDisplay"
 		style="@style/display_style"
 		a:layout_weight="1"
 		a:minLines="1"

res/layout/calc_donate_button.xml

@@ -0,0 +1,15 @@
+<?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"
+			 xmlns:calc="http://schemas.android.com/apk/res/org.solovyev.android.calculator"
+			 a:id="@+id/pasteButton"
+			 a:src="@drawable/heart"
+			 style="@style/control_button_style"
+			 a:padding="6dp"
+			 a:onClick="donateButtonClickHandler"/>

res/layout/calc_editor.xml

@@ -12,7 +12,7 @@
 			  a:layout_height="0dp">
 
 	<org.solovyev.android.calculator.CalculatorEditor
-			a:id="@+id/editText"
+			a:id="@+id/calculatorEditor"
 			style="@style/editor_style"
 			a:inputType="textMultiLine"
 			a:maxLines="4"

res/values-ru/strings.xml

@@ -55,4 +55,5 @@
 	<string name="c_pi_description">Отношение длины окружности к диаметру</string>
 	<string name="c_e_description">Вещесвтенное число, такое что производная функции f(x) = e^x в точке x = 0 равно 1</string>
 	<string name="c_i_description">Мнимая единица, определённая как i^2 = −1</string>
+	<string name="c_calc_editor_hint">Введите новое выражение</string>
 </resources>

res/values/strings.xml

@@ -58,5 +58,6 @@
 	<string name="c_pi_description">Ratio of any circle\'s circumference to its diameter</string>
 	<string name="c_e_description">Unique real number such that the value of the derivative (slope of the tangent line) of the function f(x) = e^x at the point x = 0 is equal to 1</string>
 	<string name="c_i_description">Imaginary unit, defined such that i^2 = −1</string>
-	<string name="c_calc_editor_hint"></string>
+	<string name="c_calc_editor_hint">Enter new expression</string>
+	<string name="c_press_to_copy">Press to copy</string>
 </resources>

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

@@ -7,6 +7,7 @@ package org.solovyev.android.calculator;
 
 import android.app.Activity;
 import android.content.*;
+import android.net.Uri;
 import android.os.Bundle;
 import android.preference.PreferenceManager;
 import android.text.ClipboardManager;
@@ -100,6 +101,9 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 	}
 
 	private void init() {
+
+		calculatorView = new CalculatorView(this, CalculatorModel.instance);
+
 		insertTextReceiver = new BroadcastReceiver() {
 			@Override
 			public void onReceive(Context context, Intent intent) {
@@ -128,9 +132,6 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 				// todo serso: create serso runtime exception
 				throw new RuntimeException("Could not initialize interpreter!");
 			}
-
-			this.calculatorView = new CalculatorView(this, CalculatorModel.instance);
-
 			initialized = true;
 		}
 	}
@@ -191,6 +192,11 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 		});
 	}
 
+	@SuppressWarnings({"UnusedDeclaration"})
+	public void copyButtonClickHandler(@NotNull View v) {
+		calculatorView.copyResult(this);
+	}
+
 	@SuppressWarnings({"UnusedDeclaration"})
 	public void clearButtonClickHandler(@NotNull View v) {
 		calculatorView.clear();
@@ -207,6 +213,14 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 		startActivity(new Intent(this, CalculatorVarsActivity.class));
 	}
 
+	@SuppressWarnings({"UnusedDeclaration"})
+	public void donateButtonClickHandler(@NotNull View v) {
+		final String paypalDonateUrl = "https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=se%2esolovyev%40gmail%2ecom&lc=RU&item_name=android%2ecalculator%40se%2esolovyev&currency_code=USD&bn=PP%2dDonationsBF%3abtn_donateCC_LG%2egif%3aNonHosted";
+		final Intent i = new Intent(Intent.ACTION_VIEW);
+		i.setData(Uri.parse(paypalDonateUrl));
+		startActivity(i);
+	}
+
 	@Override
 	public boolean onKeyDown(int keyCode, KeyEvent event) {
 		if (keyCode == KeyEvent.KEYCODE_BACK) {

src/main/java/org/solovyev/android/calculator/CalculatorDisplayHistoryState.java

@@ -5,6 +5,7 @@
 
 package org.solovyev.android.calculator;
 
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 /**
@@ -12,19 +13,24 @@ import org.jetbrains.annotations.Nullable;
  * Date: 9/17/11
  * Time: 11:05 PM
  */
-public class CalculatorDisplayHistoryState extends EditorHistoryState {
+public class CalculatorDisplayHistoryState {
 
 	private boolean valid = true;
 
+	@NotNull
+	private final EditorHistoryState editorHistoryState;
+
 	public CalculatorDisplayHistoryState() {
+		this.editorHistoryState = new EditorHistoryState();
 	}
 
 	public CalculatorDisplayHistoryState(boolean valid) {
+		this.editorHistoryState = new EditorHistoryState();
 		this.valid = valid;
 	}
 
 	public CalculatorDisplayHistoryState(int cursorPosition, @Nullable String text, boolean valid) {
-		super(cursorPosition, text);
+		this.editorHistoryState = new EditorHistoryState(cursorPosition, text);
 		this.valid = valid;
 	}
 
@@ -35,4 +41,29 @@ public class CalculatorDisplayHistoryState extends EditorHistoryState {
 	public void setValid(boolean valid) {
 		this.valid = valid;
 	}
+
+	public EditorHistoryState getEditorHistoryState() {
+		return editorHistoryState;
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (this == o) return true;
+		if (!(o instanceof CalculatorDisplayHistoryState)) return false;
+
+		CalculatorDisplayHistoryState that = (CalculatorDisplayHistoryState) o;
+
+		if (valid != that.valid) return false;
+		if (editorHistoryState != null ? !editorHistoryState.equals(that.editorHistoryState) : that.editorHistoryState != null)
+			return false;
+
+		return true;
+	}
+
+	@Override
+	public int hashCode() {
+		int result = (valid ? 1 : 0);
+		result = 31 * result + (editorHistoryState != null ? editorHistoryState.hashCode() : 0);
+		return result;
+	}
 }

src/main/java/org/solovyev/android/calculator/CalculatorHistory.java

@@ -0,0 +1,72 @@
+/*
+ * 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
+ */
+
+package org.solovyev.android.calculator;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.common.utils.history.HistoryAction;
+import org.solovyev.common.utils.history.HistoryHelper;
+import org.solovyev.common.utils.history.SimpleHistoryHelper;
+
+/**
+ * User: serso
+ * Date: 10/9/11
+ * Time: 6:35 PM
+ */
+public enum CalculatorHistory implements HistoryHelper<CalculatorHistoryState> {
+
+	instance;
+
+	private final HistoryHelper<CalculatorHistoryState> historyHelper = new SimpleHistoryHelper<CalculatorHistoryState>();
+
+	@Override
+	public boolean isEmpty() {
+		return this.historyHelper.isEmpty();
+	}
+
+	@Override
+	public CalculatorHistoryState getLastHistoryState() {
+		return this.historyHelper.getLastHistoryState();
+	}
+
+	@Override
+	public boolean isUndoAvailable() {
+		return historyHelper.isUndoAvailable();
+	}
+
+	@Override
+	public CalculatorHistoryState undo(@Nullable CalculatorHistoryState currentState) {
+		return historyHelper.undo(currentState);
+	}
+
+	@Override
+	public boolean isRedoAvailable() {
+		return historyHelper.isRedoAvailable();
+	}
+
+	@Override
+	public CalculatorHistoryState redo(@Nullable CalculatorHistoryState currentState) {
+		return historyHelper.redo(currentState);
+	}
+
+	@Override
+	public boolean isActionAvailable(@NotNull HistoryAction historyAction) {
+		return historyHelper.isActionAvailable(historyAction);
+	}
+
+	@Override
+	public CalculatorHistoryState doAction(@NotNull HistoryAction historyAction, @Nullable CalculatorHistoryState currentState) {
+		return historyHelper.doAction(historyAction, currentState);
+	}
+
+	@Override
+	public void addState(@Nullable CalculatorHistoryState currentState) {
+		historyHelper.addState(currentState);
+	}
+
+
+}

src/main/java/org/solovyev/android/calculator/CalculatorView.java

@@ -6,6 +6,7 @@
 package org.solovyev.android.calculator;
 
 import android.app.Activity;
+import android.content.Context;
 import android.os.Handler;
 import android.text.ClipboardManager;
 import android.util.Log;
@@ -21,11 +22,10 @@ import org.solovyev.android.calculator.model.CalculatorModel;
 import org.solovyev.android.calculator.model.ParseException;
 import org.solovyev.android.view.CursorControl;
 import org.solovyev.android.view.HistoryControl;
+import org.solovyev.android.view.widgets.SoftKeyboardDisabler;
 import org.solovyev.common.utils.MutableObject;
 import org.solovyev.common.utils.StringUtils;
 import org.solovyev.common.utils.history.HistoryAction;
-import org.solovyev.common.utils.history.HistoryHelper;
-import org.solovyev.common.utils.history.SimpleHistoryHelper;
 
 /**
  * User: serso
@@ -46,35 +46,43 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 	@NotNull
 	private final CalculatorModel calculatorModel;
 
-	@NotNull
-	private final HistoryHelper<CalculatorHistoryState> history;
-
 	public CalculatorView(@NotNull final Activity activity, @NotNull CalculatorModel calculator) {
 		this.calculatorModel = calculator;
 
-		this.editor = (CalculatorEditor) activity.findViewById(R.id.editText);
+		this.editor = (CalculatorEditor) activity.findViewById(R.id.calculatorEditor);
+		this.editor.setOnTouchListener(new SoftKeyboardDisabler());
 
-		this.display = (CalculatorDisplay) activity.findViewById(R.id.resultEditText);
+		this.display = (CalculatorDisplay) activity.findViewById(R.id.calculatorDisplay);
 		this.display.setOnClickListener(new View.OnClickListener() {
 			@Override
 			public void onClick(View v) {
-				if (((CalculatorDisplay) v).isValid()) {
+				copyResult(activity);
-					final CharSequence text = ((TextView) v).getText();
-					if (!StringUtils.isEmpty(text)) {
-						final ClipboardManager clipboard = (ClipboardManager) activity.getSystemService(Activity.CLIPBOARD_SERVICE);
-						clipboard.setText(text);
-						Toast.makeText(activity, activity.getText(R.string.c_result_copied), Toast.LENGTH_SHORT).show();
-					}
-				}
 			}
 		});
 
-		this.history = new SimpleHistoryHelper<CalculatorHistoryState>();
+
+		final CalculatorHistoryState lastState = CalculatorHistory.instance.getLastHistoryState();
+		if ( lastState == null ) {
 			saveHistoryState();
+		} else {
+			setCurrentHistoryState(lastState);
+		}
+
+	}
+
+	public void copyResult(@NotNull Context context) {
+		if (display.isValid()) {
+			final CharSequence text = display.getText();
+			if (!StringUtils.isEmpty(text)) {
+				final ClipboardManager clipboard = (ClipboardManager) context.getSystemService(Activity.CLIPBOARD_SERVICE);
+				clipboard.setText(text);
+				Toast.makeText(context, context.getText(R.string.c_result_copied), Toast.LENGTH_SHORT).show();
+			}
+		}
 	}
 
 	private void saveHistoryState() {
-		history.addState(getCurrentHistoryState());
+		CalculatorHistory.instance.addState(getCurrentHistoryState());
 	}
 
 
@@ -117,14 +125,14 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 					// allow only one runner at one time
 					synchronized (currentRunner) {
 						//lock all operations with history
-						synchronized (history) {
+						synchronized (CalculatorHistory.instance) {
 							// do only if nothing was post delayed before current instance was posted
 							if (currentRunner.getObject() == this) {
 								// actually nothing shall be logged while text operations are done
 								evaluate(editorStateAfter);
 
-								if (history.isUndoAvailable()) {
+								if (CalculatorHistory.instance.isUndoAvailable()) {
-									history.undo(getCurrentHistoryState());
+									CalculatorHistory.instance.undo(getCurrentHistoryState());
 								}
 
 								saveHistoryState();
@@ -212,9 +220,9 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 
 	@Override
 	public void doHistoryAction(@NotNull HistoryAction historyAction) {
-		synchronized (history) {
+		synchronized (CalculatorHistory.instance) {
-			if (history.isActionAvailable(historyAction)) {
+			if (CalculatorHistory.instance.isActionAvailable(historyAction)) {
-				final CalculatorHistoryState newState = history.doAction(historyAction, getCurrentHistoryState());
+				final CalculatorHistoryState newState = CalculatorHistory.instance.doAction(historyAction, getCurrentHistoryState());
 				if (newState != null) {
 					setCurrentHistoryState(newState);
 				}
@@ -224,7 +232,7 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 
 	@Override
 	public void setCurrentHistoryState(@NotNull CalculatorHistoryState editorHistoryState) {
-		synchronized (history) {
+		synchronized (CalculatorHistory.instance) {
 			setValuesFromHistory(this.editor, editorHistoryState.getEditorState());
 			setValuesFromHistory(this.display, editorHistoryState.getDisplayState());
 
@@ -233,7 +241,7 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 	}
 
 	private void setValuesFromHistory(@NotNull CalculatorDisplay display, CalculatorDisplayHistoryState editorHistoryState) {
-		setValuesFromHistory(display, (EditorHistoryState)editorHistoryState);
+		setValuesFromHistory(display, editorHistoryState.getEditorHistoryState());
 		display.setValid(editorHistoryState.isValid());
 	}
 
@@ -247,7 +255,7 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 	@Override
 	@NotNull
 	public CalculatorHistoryState getCurrentHistoryState() {
-		synchronized (history) {
+		synchronized (CalculatorHistory.instance) {
 			return new CalculatorHistoryState(getEditorHistoryState(this.editor), getCalculatorDisplayHistoryState(this.display));
 		}
 	}
@@ -264,8 +272,8 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 	private CalculatorDisplayHistoryState getCalculatorDisplayHistoryState(@NotNull CalculatorDisplay display) {
 		final CalculatorDisplayHistoryState result = new CalculatorDisplayHistoryState();
 
-		result.setText(String.valueOf(display.getText()));
+		result.getEditorHistoryState().setText(String.valueOf(display.getText()));
-		result.setCursorPosition(display.getSelectionStart());
+		result.getEditorHistoryState().setCursorPosition(display.getSelectionStart());
 		result.setValid(display.isValid());
 
 		return result;

src/main/java/org/solovyev/android/calculator/EditorHistoryState.java

@@ -39,5 +39,23 @@ public class EditorHistoryState {
 		return cursorPosition;
 	}
 
+	@Override
+	public boolean equals(Object o) {
+		if (this == o) return true;
+		if (!(o instanceof EditorHistoryState)) return false;
 
+		EditorHistoryState that = (EditorHistoryState) o;
+
+		if (cursorPosition != that.cursorPosition) return false;
+		if (text != null ? !text.equals(that.text) : that.text != null) return false;
+
+		return true;
+	}
+
+	@Override
+	public int hashCode() {
+		int result = cursorPosition;
+		result = 31 * result + (text != null ? text.hashCode() : 0);
+		return result;
+	}
 }

src/main/java/org/solovyev/android/calculator/math/Functions.java

@@ -37,11 +37,13 @@ public class Functions {
 	public final static String EXP = "exp";
 	public final static String SQRT_SIGN = "√";
 	public final static String SQRT = "sqrt";
+	public final static String E = "E";
+	public final static String E_POWER = "10^";
 
 	public static final List<String> allPrefix;
 
 	static {
-		final List<String> functions = new ArrayList<String>(Arrays.asList(SIN, SINH, ASIN, ASINH, COS, COSH, ACOS, ACOSH, TAN, TANH, ATAN, ATANH, LOG, LN, MOD, SQRT, SQRT_SIGN, EXP));
+		final List<String> functions = new ArrayList<String>(Arrays.asList(SIN, SINH, ASIN, ASINH, COS, COSH, ACOS, ACOSH, TAN, TANH, ATAN, ATANH, LOG, LN, MOD, SQRT, SQRT_SIGN, EXP, E));
 		Collections.sort(functions, new MathEntityComparator());
 		allPrefix = functions;
 	}

src/main/java/org/solovyev/android/calculator/model/ToJsclTextProcessor.java

@@ -39,10 +39,10 @@ class ToJsclTextProcessor implements TextProcessor {
 				sb.append(')');
 			} else if (ch == '×' || ch == '∙') {
 				sb.append("*");
-			} else if ( mathType == MathType.function  ){
+			} else if (mathType == MathType.function) {
 				sb.append(toJsclFunction(mathTypeResult.getMatch()));
 				i += mathTypeResult.getMatch().length() - 1;
-			} else if ( mathType == MathType.constant ) {
+			} else if (mathType == MathType.constant) {
 				sb.append(mathTypeResult.getMatch());
 				i += mathTypeResult.getMatch().length() - 1;
 			} else {
@@ -148,6 +148,8 @@ class ToJsclTextProcessor implements TextProcessor {
 			result = Functions.LOG;
 		} else if (function.equals(Functions.SQRT_SIGN)) {
 			result = Functions.SQRT;
+		} else if (function.equals(Functions.E)) {
+			result = Functions.E_POWER;
 		} else {
 			result = function;
 		}

src/main/java/org/solovyev/android/view/widgets/DirectionDragButton.java

@@ -13,8 +13,6 @@ import android.text.TextPaint;
 import android.util.AttributeSet;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.solovyev.android.view.widgets.DragButton;
-import org.solovyev.android.view.widgets.DragDirection;
 import org.solovyev.common.utils.Point2d;
 import org.solovyev.common.utils.StringUtils;
 
@@ -101,11 +99,11 @@ public class DirectionDragButton extends DragButton {
 		initUpDownTextPaint(basePaint);
 
 		if (textUp != null) {
-			textUpPosition = getTextPosition(upDownTextPaint, basePaint, textUp, 1);
+			textUpPosition = getTextPosition(upDownTextPaint, basePaint, textUp, getText(), 1, getWidth(), getHeight());
 		}
 
 		if (textDown != null) {
-			textDownPosition = getTextPosition(upDownTextPaint, basePaint, textDown, -1);
+			textDownPosition = getTextPosition(upDownTextPaint, basePaint, textDown, getText(), -1, getWidth(), getHeight());
 		}
 
 		if ( textDownPosition != null && textUpPosition != null ) {
@@ -118,21 +116,21 @@ public class DirectionDragButton extends DragButton {
 
 	}
 
-	private Point2d getTextPosition(@NotNull Paint paint, @NotNull Paint basePaint, @NotNull CharSequence text, float direction) {
+	public static Point2d getTextPosition(@NotNull Paint paint, @NotNull Paint basePaint, @NotNull CharSequence text, CharSequence baseText, float direction, int w, int h) {
 		final Point2d result = new Point2d();
 
 		float width = paint.measureText(text.toString() + " ");
-		result.setX(getWidth() - width);
+		result.setX(w - width);
 
 		float selfHeight = paint.ascent() + paint.descent();
 
-		basePaint.measureText(StringUtils.getNotEmpty(getText(), "|"));
+		basePaint.measureText(StringUtils.getNotEmpty(baseText, "|"));
 
-		float height = getHeight() - basePaint.ascent() - basePaint.descent();
+		float height = h - basePaint.ascent() - basePaint.descent();
 		if (direction < 0) {
-			result.setY(height / 2 - direction * height / 3 + selfHeight);
+			result.setY(height / 2 + height / 3 + selfHeight);
 		} else {
-			result.setY(height / 2 - direction * height / 3);
+			result.setY(height / 2 - height / 3);
 		}
 
 		return result;

src/main/java/org/solovyev/android/view/widgets/SoftKeyboardDisabler.java

@@ -0,0 +1,50 @@
+/*
+ * 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
+ */
+
+package org.solovyev.android.view.widgets;
+
+import android.text.InputType;
+import android.util.Log;
+import android.view.MotionEvent;
+import android.view.View;
+import android.widget.EditText;
+
+/**
+ * User: serso
+ * Date: 10/9/11
+ * Time: 4:27 PM
+ */
+public class SoftKeyboardDisabler implements View.OnTouchListener {
+
+	@Override
+	public boolean onTouch(View v, MotionEvent event) {
+		boolean result;
+		Log.d(this.getClass().getName(), "org.solovyev.android.view.widgets.SoftKeyboardDisabler.onTouch(): action=" + event.getAction() + ", event=" + event);
+
+		if (v instanceof EditText) {
+			final EditText editText = (EditText) v;
+			int inputType = editText.getInputType();
+			int selectionStart = editText.getSelectionStart();
+			int selectionEnd = editText.getSelectionEnd();
+
+			// disable soft input
+			editText.setInputType(InputType.TYPE_NULL);
+			editText.onTouchEvent(event);
+
+			// restore input type
+			editText.setInputType(inputType);
+			editText.setSelection(selectionStart, selectionEnd);
+
+			result = true;
+		} else {
+			result = false;
+		}
+
+		return result;
+	}
+
+
+}

src/test/java/org/solovyev/android/calculator/model/ToJsclPreprocessorTest.java

@@ -7,6 +7,7 @@
 package org.solovyev.android.calculator.model;
 
 import org.junit.Assert;
+import org.junit.BeforeClass;
 import org.junit.Test;
 
 /**
@@ -16,16 +17,23 @@ import org.junit.Test;
  */
 public class ToJsclPreprocessorTest {
 
+	@BeforeClass
+	public static void setUp() throws Exception {
+		CalculatorModel.instance.init(null);
+	}
+
 	@Test
 	public void testProcess() throws Exception {
 		final ToJsclTextProcessor preprocessor = new ToJsclTextProcessor();
 
 		Assert.assertEquals( "sin(4)*cos(5)", preprocessor.process("sin(4)cos(5)"));
-		Assert.assertEquals( "pi*sin(4)*pi*cos(sqrt(5))", preprocessor.process("πsin(4)πcos(√(5))"));
+		Assert.assertEquals( "3.141592653589793*sin(4)*3.141592653589793*cos(sqrt(5))", preprocessor.process("πsin(4)πcos(√(5))"));
-		Assert.assertEquals( "pi*sin(4)+pi*cos(sqrt(5))", preprocessor.process("πsin(4)+πcos(√(5))"));
+		Assert.assertEquals( "3.141592653589793*sin(4)+3.141592653589793*cos(sqrt(5))", preprocessor.process("πsin(4)+πcos(√(5))"));
-		Assert.assertEquals( "pi*sin(4)+pi*cos(sqrt(5+sqrt(-1)))", preprocessor.process("πsin(4)+πcos(√(5+i))"));
+		Assert.assertEquals( "3.141592653589793*sin(4)+3.141592653589793*cos(sqrt(5+sqrt(-1)))", preprocessor.process("πsin(4)+πcos(√(5+i))"));
-		Assert.assertEquals( "pi*sin(4.01)+pi*cos(sqrt(5+sqrt(-1)))", preprocessor.process("πsin(4.01)+πcos(√(5+i))"));
+		Assert.assertEquals( "3.141592653589793*sin(4.01)+3.141592653589793*cos(sqrt(5+sqrt(-1)))", preprocessor.process("πsin(4.01)+πcos(√(5+i))"));
-		Assert.assertEquals( "exp(1)^pi*sin(4.01)+pi*cos(sqrt(5+sqrt(-1)))", preprocessor.process("e^πsin(4.01)+πcos(√(5+i))"));
+		Assert.assertEquals( "2.718281828459045^3.141592653589793*sin(4.01)+3.141592653589793*cos(sqrt(5+sqrt(-1)))", preprocessor.process("e^πsin(4.01)+πcos(√(5+i))"));
+		Assert.assertEquals( "2.718281828459045^3.141592653589793*sin(4.01)+3.141592653589793*cos(sqrt(5+sqrt(-1)))*10^2", preprocessor.process("e^πsin(4.01)+πcos(√(5+i))E2"));
+		Assert.assertEquals( "2.718281828459045^3.141592653589793*sin(4.01)+3.141592653589793*cos(sqrt(5+sqrt(-1)))*10^-2", preprocessor.process("e^πsin(4.01)+πcos(√(5+i))E-2"));
 	}
 
 	@Test
@@ -44,7 +52,7 @@ public class ToJsclPreprocessorTest {
 		Assert.assertEquals(4, preprocessor.getPostfixFunctionStart("2.23+(5.4434234*sin(5.1+1))!", 26));
 		Assert.assertEquals(0, preprocessor.getPostfixFunctionStart("sin(5)!", 5));
 		Assert.assertEquals(0, preprocessor.getPostfixFunctionStart("sin(5sin(5sin(5)))!", 17));
-		Assert.assertEquals(1, preprocessor.getPostfixFunctionStart("2+sin(5sin(5sin(5)))!", 19));
+		Assert.assertEquals(2, preprocessor.getPostfixFunctionStart("2+sin(5sin(5sin(5)))!", 19));
-		Assert.assertEquals(4, preprocessor.getPostfixFunctionStart("2.23+sin(5.4434234*sin(5.1+1))!", 29));
+		Assert.assertEquals(5, preprocessor.getPostfixFunctionStart("2.23+sin(5.4434234*sin(5.1+1))!", 29));
 	}
 }