Greek keyboard

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

@@ -29,37 +29,34 @@ import android.content.Intent;
 import android.content.SharedPreferences;
 import android.net.Uri;
 import android.preference.PreferenceManager;
-import android.support.v7.app.AppCompatActivity;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.widget.TextView;
-
+import jscl.math.Generic;
+import jscl.math.function.Constant;
 import org.solovyev.android.Activities;
 import org.solovyev.android.calculator.about.CalculatorAboutActivity;
 import org.solovyev.android.calculator.functions.CppFunction;
 import org.solovyev.android.calculator.functions.EditFunctionFragment;
-import org.solovyev.android.calculator.history.CalculatorHistoryActivity;
 import org.solovyev.android.calculator.functions.FunctionsActivity;
+import org.solovyev.android.calculator.history.CalculatorHistoryActivity;
 import org.solovyev.android.calculator.math.edit.OperatorsActivity;
-import org.solovyev.android.calculator.variables.VariablesActivity;
-import org.solovyev.android.calculator.variables.EditVariableFragment;
-import org.solovyev.android.calculator.variables.VariablesFragment;
 import org.solovyev.android.calculator.matrix.CalculatorMatrixActivity;
 import org.solovyev.android.calculator.plot.CalculatorPlotActivity;
 import org.solovyev.android.calculator.plot.CalculatorPlotter;
 import org.solovyev.android.calculator.preferences.PreferencesActivity;
+import org.solovyev.android.calculator.variables.CppVariable;
+import org.solovyev.android.calculator.variables.EditVariableFragment;
+import org.solovyev.android.calculator.variables.VariablesActivity;
+import org.solovyev.android.calculator.variables.VariablesFragment;
 import org.solovyev.common.msg.Message;
 import org.solovyev.common.msg.MessageType;
 import org.solovyev.common.text.Strings;
 
-import java.util.List;
-import java.util.Set;
-
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-
+import java.util.List;
-import jscl.math.Generic;
+import java.util.Set;
-import jscl.math.function.Constant;
 
 /**
  * User: serso
@@ -140,19 +137,12 @@ public final class CalculatorActivityLauncher implements CalculatorEventListener
 
     public static void tryCreateVar(@Nonnull final Context context) {
         final Display display = App.getDisplay();
-        final DisplayState viewState = display.getState();
+        final DisplayState state = display.getState();
-        if (viewState.valid) {
+        if (state.valid) {
-            final String varValue = viewState.text;
+            final String value = state.text;
-            if (!Strings.isEmpty(varValue)) {
+            if (!Strings.isEmpty(value)) {
-                if (VariablesFragment.isValidValue(varValue)) {
+                if (VariablesFragment.isValidValue(value)) {
-                    if (context instanceof AppCompatActivity) {
+                    EditVariableFragment.showDialog(CppVariable.builder("").withValue(value).build(), context);
-                        EditVariableFragment.showDialog(EditVariableFragment.Input.newFromValue(varValue), ((AppCompatActivity) context).getSupportFragmentManager());
-                    } else {
-                        final Intent intent = new Intent(context, VariablesActivity.class);
-                        intent.putExtra(VariablesFragment.CREATE_VAR_EXTRA_STRING, varValue);
-                        Activities.addIntentFlags(intent, false, context);
-                        context.startActivity(intent);
-                    }
                 } else {
                     getNotifier().showMessage(R.string.c_value_is_not_a_number, MessageType.error);
                 }

app/src/main/java/org/solovyev/android/calculator/FloatingCalculatorKeyboard.java

@@ -1,26 +1,16 @@
 package org.solovyev.android.calculator;
 
-import android.content.Context;
-import android.content.res.Resources;
-import android.graphics.Color;
 import android.graphics.PointF;
-import android.os.Build;
-import android.support.annotation.ColorInt;
-import android.support.annotation.DrawableRes;
 import android.support.annotation.IdRes;
 import android.support.annotation.NonNull;
 import android.text.TextUtils;
-import android.util.TypedValue;
 import android.view.HapticFeedbackConstants;
 import android.view.MotionEvent;
 import android.view.View;
-import android.view.ViewGroup;
 import android.widget.Button;
-import android.widget.EditText;
-import android.widget.ImageButton;
-import android.widget.ImageView;
 import android.widget.LinearLayout;
-
+import org.solovyev.android.calculator.keyboard.BaseFloatingKeyboard;
+import org.solovyev.android.calculator.keyboard.FloatingKeyboard;
 import org.solovyev.android.calculator.view.EditTextLongClickEraser;
 import org.solovyev.android.views.dragbutton.DirectionDragButton;
 import org.solovyev.android.views.dragbutton.DragButton;
@@ -33,35 +23,20 @@ import static org.solovyev.android.views.dragbutton.DirectionDragButton.Directio
 import static org.solovyev.android.views.dragbutton.DirectionDragButton.Direction.up;
 
 
-public class KeyboardUi {
+public class FloatingCalculatorKeyboard extends BaseFloatingKeyboard {
     @NonNull
     private final ButtonHandler buttonHandler = new ButtonHandler();
     @NonNull
-    private final User user;
-    @NonNull
     private final List<String> parameterNames;
     @NonNull
     private final SimpleDragListener dragListener;
-    @ColorInt
-    private final int textColor;
-    @ColorInt
-    private final int textColorSecondary;
-    private final int sidePadding;
-    @DrawableRes
-    private final int buttonBackground;
     @NonNull
     private final String multiplicationSign = Locator.getInstance().getEngine().getMultiplicationSign();
 
-    @SuppressWarnings("deprecation")
+    public FloatingCalculatorKeyboard(@NonNull User user, @NonNull List<String> parameterNames) {
-    public KeyboardUi(@NonNull User user, @NonNull List<String> parameterNames) {
+        super(user);
-        this.user = user;
         this.parameterNames = parameterNames;
         this.dragListener = new SimpleDragListener(buttonHandler, user.getContext());
-        final Resources resources = user.getResources();
-        textColor = resources.getColor(R.color.cpp_kb_button_text);
-        textColorSecondary = resources.getColor(R.color.cpp_kb_button_text);
-        sidePadding = resources.getDimensionPixelSize(R.dimen.cpp_button_padding);
-        buttonBackground = App.getTheme().light ? R.drawable.material_button_light : R.drawable.material_button_dark;
     }
 
     public void makeView(boolean landscape) {
@@ -72,6 +47,26 @@ public class KeyboardUi {
         }
     }
 
+    @NonNull
+    @Override
+    public User getUser() {
+        return (User) super.getUser();
+    }
+
+    @Override
+    protected void fillButton(@NonNull View button, @IdRes int id) {
+        super.fillButton(button, id);
+        button.setOnClickListener(buttonHandler);
+    }
+
+    @NonNull
+    @Override
+    protected DirectionDragButton makeButton(@IdRes int id, @NonNull String text) {
+        final DirectionDragButton button = super.makeButton(id, text);
+        button.setOnDragListener(dragListener);
+        return button;
+    }
+
     private void makeViewLand() {
         final int parametersCount = parameterNames.size();
 
@@ -146,74 +141,6 @@ public class KeyboardUi {
         addImageButton(row, R.id.cpp_kb_button_close, R.drawable.ic_done_white_24dp);
     }
 
-    @NonNull
-    private View addImageButton(@NonNull LinearLayout row, @IdRes int id, @DrawableRes int icon) {
-        final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(0, ViewGroup.LayoutParams.MATCH_PARENT);
-        lp.weight = 1f;
-        final View view = makeImageButton(id, icon);
-        row.addView(view, lp);
-        return view;
-    }
-
-    @NonNull
-    private DirectionDragButton addOperationButton(@NonNull LinearLayout row, @IdRes int id, @NonNull String text) {
-        final DirectionDragButton button = addButton(row, id, text);
-        button.setBackgroundResource(R.drawable.material_button_light_primary);
-        button.setTextColor(Color.WHITE);
-        button.setDirectionTextColor(Color.WHITE);
-        return button;
-    }
-
-    @NonNull
-    private DirectionDragButton addButton(@NonNull LinearLayout row, @IdRes int id, @NonNull String text) {
-        final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(0, ViewGroup.LayoutParams.MATCH_PARENT);
-        lp.weight = 1f;
-        final DirectionDragButton view = makeButton(id, text);
-        row.addView(view, lp);
-        return view;
-    }
-
-    @NonNull
-    private LinearLayout makeRow() {
-        final LinearLayout row = new LinearLayout(user.getContext());
-        row.setOrientation(LinearLayout.HORIZONTAL);
-        final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 0);
-        lp.weight = 1f;
-        user.getKeyboard().addView(row, lp);
-        return row;
-    }
-
-    @NonNull
-    private DirectionDragButton makeButton(@IdRes int id, @NonNull String text) {
-        final DirectionDragButton button = new DirectionDragButton(user.getContext());
-        fillButton(button, id);
-        button.setText(text);
-        button.setTextColor(textColor);
-        button.setDirectionTextColor(textColorSecondary);
-        button.setTextSize(TypedValue.COMPLEX_UNIT_DIP, 24);
-        button.setOnDragListener(dragListener);
-        return button;
-    }
-
-    private void fillButton(@NonNull View button, @IdRes int id) {
-        button.setOnClickListener(buttonHandler);
-        button.setId(id);
-        button.setBackgroundResource(buttonBackground);
-        button.setPadding(sidePadding, 1, sidePadding, 1);
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
-            button.setStateListAnimator(null);
-        }
-    }
-
-    @NonNull
-    private View makeImageButton(@IdRes int id, @DrawableRes int icon) {
-        final ImageButton button = new ImageButton(user.getContext());
-        fillButton(button, id);
-        button.setImageResource(icon);
-        button.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
-        return button;
-    }
-
     public int getRowsCount(boolean landscape) {
         return landscape ? 3 : 5;
     }
@@ -222,18 +149,7 @@ public class KeyboardUi {
         return landscape ? 8 : 5;
     }
 
-    public interface User {
+    public interface User extends FloatingKeyboard.User {
-        @NonNull
-        Context getContext();
-
-        @NonNull
-        Resources getResources();
-
-        @NonNull
-        EditText getEditor();
-
-        @NonNull
-        ViewGroup getKeyboard();
 
         void insertOperator(char operator);
 
@@ -243,16 +159,17 @@ public class KeyboardUi {
 
         void showConstants(@NonNull View v);
 
+        void showFunctionsConstants(@NonNull View v);
+
         void insertText(@NonNull CharSequence text, int offset);
 
-        void done();
-
-        void showIme();
-
-        void showFunctionsConstants(@NonNull View v);
     }
 
     private class ButtonHandler implements View.OnClickListener, SimpleDragListener.DragProcessor {
+
+        @NonNull
+        private final User user = getUser();
+
         @Override
         public void onClick(@NonNull View v) {
             switch (v.getId()) {

app/src/main/java/org/solovyev/android/calculator/functions/EditFunctionFragment.java

@@ -33,7 +33,6 @@ import android.support.design.widget.TextInputLayout;
 import android.support.v4.app.FragmentActivity;
 import android.support.v4.app.FragmentManager;
 import android.support.v7.app.AlertDialog;
-import android.support.v7.app.AppCompatActivity;
 import android.text.Editable;
 import android.text.TextUtils;
 import android.view.*;
@@ -43,8 +42,10 @@ import android.widget.EditText;
 import butterknife.Bind;
 import butterknife.ButterKnife;
 import jscl.math.function.Function;
+import org.solovyev.android.Activities;
 import org.solovyev.android.Check;
 import org.solovyev.android.calculator.*;
+import org.solovyev.android.calculator.keyboard.FloatingKeyboardWindow;
 import org.solovyev.android.calculator.math.edit.VarEditorSaver;
 import org.solovyev.android.calculator.view.EditTextCompat;
 import org.solovyev.common.math.MathRegistry;
@@ -66,7 +67,7 @@ public class EditFunctionFragment extends BaseDialogFragment implements View.OnC
     @NonNull
     private final VariablesRegistry constantsRegistry = Locator.getInstance().getEngine().getVariablesRegistry();
     @NonNull
-    private final KeyboardWindow keyboardWindow = new KeyboardWindow();
+    private final FloatingKeyboardWindow keyboardWindow = new FloatingKeyboardWindow();
     @NonNull
     private final KeyboardUser keyboardUser = new KeyboardUser();
     @Bind(R.id.function_params)
@@ -103,14 +104,14 @@ public class EditFunctionFragment extends BaseDialogFragment implements View.OnC
         EditFunctionFragment.showDialog(null, activity.getSupportFragmentManager());
     }
 
-    public static void showDialog(@Nonnull CppFunction function, @Nonnull Context context) {
+    public static void showDialog(@Nullable CppFunction function, @Nonnull Context context) {
         if (!(context instanceof FunctionsActivity)) {
             final Intent intent = new Intent(context, FunctionsActivity.class);
-            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+            Activities.addIntentFlags(intent, false, context);
             intent.putExtra(FunctionsActivity.EXTRA_FUNCTION, function);
             context.startActivity(intent);
         } else {
-            EditFunctionFragment.showDialog(function, ((AppCompatActivity) context).getSupportFragmentManager());
+            EditFunctionFragment.showDialog(function, ((FunctionsActivity) context).getSupportFragmentManager());
         }
     }
 
@@ -228,7 +229,7 @@ public class EditFunctionFragment extends BaseDialogFragment implements View.OnC
     }
 
     private void showKeyboard() {
-        keyboardWindow.show(keyboardUser, getDialog(), collectParameters());
+        keyboardWindow.show(new FloatingCalculatorKeyboard(keyboardUser, collectParameters()), getDialog());
     }
 
     @Nonnull
@@ -379,7 +380,7 @@ public class EditFunctionFragment extends BaseDialogFragment implements View.OnC
         return view;
     }
 
-    private class KeyboardUser implements KeyboardUi.User, MenuItem.OnMenuItemClickListener {
+    private class KeyboardUser implements FloatingCalculatorKeyboard.User, MenuItem.OnMenuItemClickListener {
         @NonNull
         @Override
         public Context getContext() {

app/src/main/java/org/solovyev/android/calculator/functions/FunctionsActivity.java

@@ -52,7 +52,7 @@ public class FunctionsActivity extends BaseActivity {
         if (savedInstanceState == null) {
             final Bundle extras = getIntent().getExtras();
             final CppFunction function = extras != null ? (CppFunction) extras.getParcelable(EXTRA_FUNCTION) : null;
-            EditFunctionFragment.showDialog(function, getSupportFragmentManager());
+            EditFunctionFragment.showDialog(function, this);
         }
     }
 

app/src/main/java/org/solovyev/android/calculator/keyboard/BaseFloatingKeyboard.java

@@ -0,0 +1,117 @@
+package org.solovyev.android.calculator.keyboard;
+
+import android.content.res.Resources;
+import android.graphics.Color;
+import android.os.Build;
+import android.support.annotation.ColorInt;
+import android.support.annotation.DrawableRes;
+import android.support.annotation.IdRes;
+import android.support.annotation.NonNull;
+import android.text.TextUtils;
+import android.util.TypedValue;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ImageButton;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import org.solovyev.android.calculator.App;
+import org.solovyev.android.calculator.R;
+import org.solovyev.android.views.dragbutton.DirectionDragButton;
+
+public abstract class BaseFloatingKeyboard implements FloatingKeyboard {
+
+    @NonNull
+    protected final User user;
+    @ColorInt
+    private final int textColor;
+    @ColorInt
+    private final int textColorSecondary;
+    private final int sidePadding;
+    @DrawableRes
+    private final int buttonBackground;
+
+    @SuppressWarnings("deprecation")
+    protected BaseFloatingKeyboard(@NonNull User user) {
+        this.user = user;
+        final Resources resources = user.getResources();
+        textColor = resources.getColor(R.color.cpp_kb_button_text);
+        textColorSecondary = resources.getColor(R.color.cpp_kb_button_text);
+        sidePadding = resources.getDimensionPixelSize(R.dimen.cpp_button_padding);
+        buttonBackground = App.getTheme().light ? R.drawable.material_button_light : R.drawable.material_button_dark;
+    }
+
+    @NonNull
+    @Override
+    public User getUser() {
+        return user;
+    }
+
+    @NonNull
+    protected final LinearLayout makeRow() {
+        final LinearLayout row = new LinearLayout(user.getContext());
+        row.setOrientation(LinearLayout.HORIZONTAL);
+        final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 0);
+        lp.weight = 1f;
+        user.getKeyboard().addView(row, lp);
+        return row;
+    }
+
+    @NonNull
+    protected DirectionDragButton makeButton(@IdRes int id, @NonNull String text) {
+        final DirectionDragButton button = new DirectionDragButton(user.getContext());
+        fillButton(button, id);
+        button.setText(text);
+        button.setTextColor(textColor);
+        button.setDirectionTextColor(textColorSecondary);
+        button.setTextSize(TypedValue.COMPLEX_UNIT_DIP, 24);
+        if (TextUtils.isEmpty(text)) {
+            button.setEnabled(false);
+        }
+        return button;
+    }
+
+    protected void fillButton(@NonNull View button, @IdRes int id) {
+        button.setId(id);
+        button.setBackgroundResource(buttonBackground);
+        button.setPadding(sidePadding, 1, sidePadding, 1);
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            button.setStateListAnimator(null);
+        }
+    }
+
+    @NonNull
+    protected final View makeImageButton(@IdRes int id, @DrawableRes int icon) {
+        final ImageButton button = new ImageButton(user.getContext());
+        fillButton(button, id);
+        button.setImageResource(icon);
+        button.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
+        return button;
+    }
+
+    @NonNull
+    protected final View addImageButton(@NonNull LinearLayout row, @IdRes int id, @DrawableRes int icon) {
+        final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(0, ViewGroup.LayoutParams.MATCH_PARENT);
+        lp.weight = 1f;
+        final View view = makeImageButton(id, icon);
+        row.addView(view, lp);
+        return view;
+    }
+
+    @NonNull
+    protected final DirectionDragButton addOperationButton(@NonNull LinearLayout row, @IdRes int id, @NonNull String text) {
+        final DirectionDragButton button = addButton(row, id, text);
+        button.setBackgroundResource(R.drawable.material_button_light_primary);
+        button.setTextColor(Color.WHITE);
+        button.setDirectionTextColor(Color.WHITE);
+        return button;
+    }
+
+    @NonNull
+    protected final DirectionDragButton addButton(@NonNull LinearLayout row, @IdRes int id, @NonNull String text) {
+        final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(0, ViewGroup.LayoutParams.MATCH_PARENT);
+        lp.weight = 1f;
+        final DirectionDragButton view = makeButton(id, text);
+        row.addView(view, lp);
+        return view;
+    }
+}

app/src/main/java/org/solovyev/android/calculator/keyboard/FloatingKeyboard.java

@@ -0,0 +1,36 @@
+package org.solovyev.android.calculator.keyboard;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.support.annotation.NonNull;
+import android.view.ViewGroup;
+import android.widget.EditText;
+
+public interface FloatingKeyboard {
+    int getRowsCount(boolean landscape);
+
+    int getColumnsCount(boolean landscape);
+
+    void makeView(boolean landscape);
+
+    @NonNull
+    User getUser();
+
+    interface User {
+        @NonNull
+        Context getContext();
+
+        @NonNull
+        Resources getResources();
+
+        @NonNull
+        EditText getEditor();
+
+        @NonNull
+        ViewGroup getKeyboard();
+
+        void done();
+
+        void showIme();
+    }
+}

app/src/main/java/org/solovyev/android/calculator/keyboard/FloatingKeyboardWindow.java

@@ -1,4 +1,4 @@
-package org.solovyev.android.calculator;
+package org.solovyev.android.calculator.keyboard;
 
 import android.app.Dialog;
 import android.content.Context;
@@ -15,10 +15,9 @@ import android.view.inputmethod.InputMethodManager;
 import android.widget.EditText;
 import android.widget.LinearLayout;
 import android.widget.PopupWindow;
+import org.solovyev.android.calculator.R;
 
-import java.util.List;
+public class FloatingKeyboardWindow {
-
-public class KeyboardWindow {
 
     @Nullable
     private PopupWindow window;
@@ -43,8 +42,8 @@ public class KeyboardWindow {
         dialog = null;
     }
 
-    public void show(@NonNull KeyboardUi.User user, @Nullable Dialog dialog, @NonNull List<String> parameterNames) {
+    public void show(@NonNull FloatingKeyboard keyboard, @Nullable Dialog dialog) {
-        final EditText editor = user.getEditor();
+        final EditText editor = keyboard.getUser().getEditor();
         if (isShown()) {
             hideIme(editor);
             return;
@@ -58,10 +57,9 @@ public class KeyboardWindow {
 
         final Resources resources = context.getResources();
         final int buttonSize = resources.getDimensionPixelSize(R.dimen.cpp_clickable_area_size);
-        final KeyboardUi keyboardUi = new KeyboardUi(user, parameterNames);
         final boolean landscape = resources.getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE;
-        final int keyboardWidth = keyboardUi.getColumnsCount(landscape) * buttonSize;
+        final int keyboardWidth = keyboard.getColumnsCount(landscape) * buttonSize;
-        final int keyboardHeight = keyboardUi.getRowsCount(landscape) * buttonSize;
+        final int keyboardHeight = keyboard.getRowsCount(landscape) * buttonSize;
 
         window = new PopupWindow(view, keyboardWidth, keyboardHeight);
         window.setClippingEnabled(false);
@@ -89,7 +87,7 @@ public class KeyboardWindow {
                 }
             }
         });
-        keyboardUi.makeView(landscape);
+        keyboard.makeView(landscape);
     }
 
     public boolean isShown() {

app/src/main/java/org/solovyev/android/calculator/math/edit/FunctionsFragment.java

@@ -44,7 +44,6 @@ import java.util.List;
 
 public class FunctionsFragment extends BaseEntitiesFragment<Function> {
 
-    public static final String ARG_FUNCTION = "function";
     @Inject
     FunctionsRegistry registry;
     @Inject
@@ -58,21 +57,6 @@ public class FunctionsFragment extends BaseEntitiesFragment<Function> {
         super(CalculatorFragmentType.functions);
     }
 
-    @Override
-    public void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-
-        final Bundle bundle = getArguments();
-        if (bundle != null) {
-            final CppFunction function = bundle.getParcelable(ARG_FUNCTION);
-            if (function != null) {
-                EditFunctionFragment.showDialog(function, getFragmentManager());
-                // don't want to show it again
-                bundle.remove(ARG_FUNCTION);
-            }
-        }
-    }
-
     @Override
     protected void inject(@Nonnull AppComponent component) {
         super.inject(component);

app/src/main/java/org/solovyev/android/calculator/math/edit/VarEditorSaver.java

@@ -87,13 +87,13 @@ public class VarEditorSaver<T extends MathEntity> implements View.OnClickListene
     public void onClick(View v) {
         final Integer error;
 
-        final EditText editName = (EditText) editView.findViewById(R.id.var_edit_name);
+        final EditText editName = (EditText) editView.findViewById(R.id.variable_name);
         String name = editName.getText().toString();
 
-        final EditText editValue = (EditText) editView.findViewById(R.id.var_edit_value);
+        final EditText editValue = (EditText) editView.findViewById(R.id.variable_value);
         String value = editValue.getText().toString();
 
-        final EditText editDescription = (EditText) editView.findViewById(R.id.var_edit_description);
+        final EditText editDescription = (EditText) editView.findViewById(R.id.variable_description);
         String description = editDescription.getText().toString();
 
         if (isValidName(name)) {

app/src/main/java/org/solovyev/android/calculator/variables/CppVariable.java

@@ -1,8 +1,10 @@
 package org.solovyev.android.calculator.variables;
 
+import android.os.Parcel;
+import android.os.Parcelable;
 import android.support.annotation.NonNull;
 import android.text.TextUtils;
-
+import jscl.math.function.IConstant;
 import org.json.JSONException;
 import org.json.JSONObject;
 import org.solovyev.android.Check;
@@ -13,11 +15,9 @@ import org.solovyev.common.JBuilder;
 
 import javax.annotation.Nonnull;
 
-import jscl.math.function.IConstant;
-
 import static com.google.common.base.Strings.nullToEmpty;
 
-public class CppVariable implements Jsonable {
+public class CppVariable implements Jsonable, Parcelable {
 
     public static final Json.Creator<CppVariable> JSON_CREATOR = new Json.Creator<CppVariable>() {
         @NonNull
@@ -26,11 +26,20 @@ public class CppVariable implements Jsonable {
             return new CppVariable(json);
         }
     };
+    public static final Creator<CppVariable> CREATOR = new Creator<CppVariable>() {
+        @Override
+        public CppVariable createFromParcel(Parcel in) {
+            return new CppVariable(in);
+        }
 
+        @Override
+        public CppVariable[] newArray(int size) {
+            return new CppVariable[size];
+        }
+    };
     private static final String JSON_NAME = "n";
     private static final String JSON_VALUE = "v";
     private static final String JSON_DESCRIPTION = "d";
-
     protected int id = CppFunction.NO_ID;
     @Nonnull
     protected String name;
@@ -66,6 +75,14 @@ public class CppVariable implements Jsonable {
         this.description = json.optString(JSON_DESCRIPTION);
     }
 
+    protected CppVariable(Parcel in) {
+        id = in.readInt();
+        name = in.readString();
+        value = in.readString();
+        description = in.readString();
+        system = in.readByte() != 0;
+    }
+
     @NonNull
     public static CppVariable.Builder builder(@NonNull String name) {
         return new Builder(name);
@@ -121,6 +138,20 @@ public class CppVariable implements Jsonable {
         return result;
     }
 
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeInt(id);
+        dest.writeString(name);
+        dest.writeString(value);
+        dest.writeString(description);
+        dest.writeByte((byte) (system ? 1 : 0));
+    }
+
     public static class Builder {
         @NonNull
         private final CppVariable variable;

app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java

@@ -22,64 +22,180 @@
 
 package org.solovyev.android.calculator.variables;
 
-import android.annotation.TargetApi;
+import android.content.Context;
-import android.os.Build;
+import android.content.Intent;
+import android.content.res.Resources;
 import android.os.Bundle;
-import android.support.v4.app.DialogFragment;
+import android.support.annotation.NonNull;
+import android.support.design.widget.TextInputLayout;
+import android.support.v4.app.FragmentActivity;
 import android.support.v4.app.FragmentManager;
+import android.support.v7.app.AlertDialog;
 import android.text.Editable;
 import android.text.TextWatcher;
+import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.*;
+import android.view.inputmethod.InputMethodManager;
-import jscl.math.function.IConstant;
+import android.widget.Button;
-import org.solovyev.android.Views;
+import android.widget.EditText;
+import android.widget.Toast;
+import butterknife.Bind;
+import butterknife.ButterKnife;
+import org.solovyev.android.Activities;
+import org.solovyev.android.Check;
 import org.solovyev.android.calculator.*;
-import org.solovyev.android.calculator.math.edit.MathEntityRemover;
+import org.solovyev.android.calculator.keyboard.FloatingKeyboard;
-import org.solovyev.android.calculator.math.edit.VarEditorSaver;
+import org.solovyev.android.calculator.keyboard.FloatingKeyboardWindow;
+import org.solovyev.android.calculator.view.EditTextCompat;
 import org.solovyev.common.text.Strings;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.Arrays;
 import java.util.List;
-import java.util.Locale;
 
-import static android.graphics.Paint.UNDERLINE_TEXT_FLAG;
+import static org.solovyev.android.calculator.functions.CppFunction.NO_ID;
-import static android.view.View.GONE;
-import static android.view.View.VISIBLE;
-import static android.view.ViewGroup.LayoutParams.MATCH_PARENT;
-import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT;
-import static android.view.WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE;
-import static android.widget.LinearLayout.HORIZONTAL;
 
-public class EditVariableFragment extends DialogFragment implements CalculatorEventListener {
+public class EditVariableFragment extends BaseDialogFragment implements CalculatorEventListener, View.OnFocusChangeListener, View.OnKeyListener, View.OnClickListener {
 
+    private static final String ARG_VARIABLE = "variable";
     private final static String greekAlphabet = "αβγδεζηθικλμνξοπρστυφχψω";
     private final static List<Character> acceptableChars = Arrays.asList(Strings.toObjects(("1234567890abcdefghijklmnopqrstuvwxyzйцукенгшщзхъфывапролджэячсмитьбюё_" + greekAlphabet).toCharArray()));
-
+    @NonNull
-    private Input input;
+    private final FloatingKeyboardWindow keyboardWindow = new FloatingKeyboardWindow();
+    @NonNull
+    private final KeyboardUser keyboardUser = new KeyboardUser();
+    @Bind(R.id.variable_name_label)
+    TextInputLayout nameLabel;
+    @Bind(R.id.variable_name)
+    EditTextCompat nameView;
+    @Bind(R.id.variable_keyboard_button)
+    Button keyboardButton;
+    @Bind(R.id.variable_value_label)
+    TextInputLayout valueLabel;
+    @Bind(R.id.variable_value)
+    EditText valueView;
+    @Bind(R.id.variable_description)
+    EditText descriptionView;
+    @Nullable
+    private CppVariable variable;
 
     public EditVariableFragment() {
-        input = Input.newInstance();
     }
 
     @Nonnull
-    public static EditVariableFragment create(@Nonnull Input input) {
+    public static EditVariableFragment create(@Nullable CppVariable variable) {
         final EditVariableFragment fragment = new EditVariableFragment();
-        fragment.input = input;
+        if (variable != null) {
+            final Bundle args = new Bundle();
+            args.putParcelable(ARG_VARIABLE, variable);
+            fragment.setArguments(args);
+        }
         return fragment;
     }
 
-    public static void showDialog(@Nonnull Input input, @Nonnull FragmentManager fm) {
+    public static void showDialog(@Nonnull FragmentActivity activity) {
-        App.showDialog(create(input), "constant-editor", fm);
+        EditVariableFragment.showDialog(null, activity.getSupportFragmentManager());
+    }
+
+    public static void showDialog(@Nullable CppVariable variable, @Nonnull Context context) {
+        if (!(context instanceof VariablesActivity)) {
+            final Intent intent = new Intent(context, VariablesActivity.class);
+            Activities.addIntentFlags(intent, false, context);
+            intent.putExtra(VariablesActivity.EXTRA_VARIABLE, variable);
+            context.startActivity(intent);
+        } else {
+            EditVariableFragment.showDialog(variable, ((VariablesActivity) context).getSupportFragmentManager());
+        }
+    }
+
+    public static void showDialog(@Nullable CppVariable variable, @Nonnull FragmentManager fm) {
+        App.showDialog(create(variable), "variable-editor", fm);
     }
 
     @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
+    public void onCreate(@android.support.annotation.Nullable Bundle savedInstanceState) {
-        return inflater.inflate(R.layout.var_edit, container, false);
+        super.onCreate(savedInstanceState);
+        final Bundle arguments = getArguments();
+        if (arguments != null) {
+            variable = arguments.getParcelable(ARG_VARIABLE);
         }
+    }
+
+    @Override
+    protected void onPrepareDialog(@NonNull AlertDialog.Builder builder) {
+        builder.setNegativeButton(R.string.c_cancel, null);
+        builder.setPositiveButton(R.string.ok, null);
+        builder.setTitle(isNewVariable() ? R.string.c_var_create_var : R.string.c_var_edit_var);
+        if (!isNewVariable()) {
+            builder.setNeutralButton(R.string.c_remove, null);
+        }
+    }
+
+    private boolean isNewVariable() {
+        return variable == null || variable.id == NO_ID;
+    }
+
+    @NonNull
+    @Override
+    public AlertDialog onCreateDialog(Bundle savedInstanceState) {
+        final AlertDialog dialog = super.onCreateDialog(savedInstanceState);
+        dialog.setCanceledOnTouchOutside(false);
+        return dialog;
+    }
+
+
+    @Override
+    protected void onShowDialog(@NonNull AlertDialog dialog) {
+        super.onShowDialog(dialog);
+
+        nameView.selectAll();
+        showIme(nameView);
+
+        final Button ok = dialog.getButton(AlertDialog.BUTTON_POSITIVE);
+        ok.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                tryClose();
+            }
+        });
+        if (!isNewVariable()) {
+            Check.isNotNull(variable);
+            final Button neutral = dialog.getButton(AlertDialog.BUTTON_NEUTRAL);
+            neutral.setOnClickListener(new View.OnClickListener() {
+                @Override
+                public void onClick(View v) {
+                    // FIXME: 2016-01-30 removal dialog
+                    // showRemovalDialog(function);
+                }
+            });
+        }
+    }
+
+    private void tryClose() {
+        if (validate() && applyData()) {
+            dismiss();
+        }
+    }
+
+    private boolean applyData() {
+        return false;
+    }
+
+    private boolean validate() {
+        return validateName() & validateValue();
+    }
+
+    private boolean validateValue() {
+        return false;
+    }
+
+    private boolean validateName() {
+        return false;
+    }
+
 
     @Override
     public void onResume() {
@@ -96,14 +212,90 @@ public class EditVariableFragment extends DialogFragment implements CalculatorEv
     }
 
     @Override
-    public void onViewCreated(@Nonnull View root, Bundle savedInstanceState) {
+    public void onCalculatorEvent(@Nonnull CalculatorEventData calculatorEventData, @Nonnull CalculatorEventType calculatorEventType, @Nullable Object data) {
-        super.onViewCreated(root, savedInstanceState);
+        switch (calculatorEventType) {
+            case constant_removed:
+            case constant_added:
+            case constant_changed:
+                if (calculatorEventData.getSource() == this) {
+                    dismiss();
+                }
+                break;
 
-        final String errorMsg = this.getString(R.string.c_char_is_not_accepted);
+        }
+    }
 
-        final EditText editName = (EditText) root.findViewById(R.id.var_edit_name);
+    @NonNull
-        editName.setText(input.getName());
+    @Override
-        editName.addTextChangedListener(new TextWatcher() {
+    protected View onCreateDialogView(@NonNull Context context, @NonNull LayoutInflater inflater, @android.support.annotation.Nullable Bundle savedInstanceState) {
+        final View view = inflater.inflate(R.layout.fragment_variable_edit, null);
+        ButterKnife.bind(this, view);
+
+        if (savedInstanceState == null && variable != null) {
+            nameView.setText(variable.name);
+            valueView.setText(variable.value);
+            descriptionView.setText(variable.description);
+        }
+        nameView.setOnFocusChangeListener(this);
+        nameView.setOnKeyListener(this);
+        valueView.setOnFocusChangeListener(this);
+        descriptionView.setOnFocusChangeListener(this);
+        keyboardButton.setOnClickListener(this);
+
+        return view;
+    }
+
+    @Override
+    public void onFocusChange(View v, boolean hasFocus) {
+        switch (v.getId()) {
+            case R.id.variable_name:
+                if (hasFocus) {
+                    clearError(nameLabel);
+                } else {
+                    keyboardUser.done();
+                }
+                break;
+            case R.id.variable_value:
+                if (hasFocus) {
+                    clearError(valueLabel);
+                } else {
+                    validateValue();
+                }
+                break;
+        }
+    }
+
+    @Override
+    public boolean onKey(View v, int keyCode, KeyEvent event) {
+        if (v.getId() == R.id.variable_name) {
+            if (event.getAction() == KeyEvent.ACTION_UP && keyCode == KeyEvent.KEYCODE_BACK && keyboardWindow.isShown()) {
+                keyboardUser.done();
+                return true;
+            }
+        }
+        return false;
+    }
+
+
+    @Override
+    public void onClick(View v) {
+        switch (v.getId()) {
+            case R.id.variable_keyboard_button:
+                if (keyboardWindow.isShown()) {
+                    keyboardUser.showIme();
+                } else {
+                    showKeyboard();
+                }
+                break;
+        }
+    }
+
+    private void showKeyboard() {
+        nameView.dontShowSoftInputOnFocusCompat();
+        keyboardWindow.show(new GreekFloatingKeyboard(keyboardUser), getDialog());
+    }
+
+    private class NameWatcher implements TextWatcher {
 
         @Override
         public void beforeTextChanged(CharSequence s, int start, int count, int after) {
@@ -119,211 +311,51 @@ public class EditVariableFragment extends DialogFragment implements CalculatorEv
                 char c = s.charAt(i);
                 if (!acceptableChars.contains(Character.toLowerCase(c))) {
                     s.delete(i, i + 1);
-                        Toast.makeText(getActivity(), String.format(errorMsg, c), Toast.LENGTH_SHORT).show();
+                    Toast.makeText(getActivity(), String.format(getString(R.string.c_char_is_not_accepted), c), Toast.LENGTH_SHORT).show();
                 }
             }
         }
-        });
-
-        fillGreekKeyboard(root, editName);
-
-        // show soft keyboard automatically
-        editName.requestFocus();
-        getDialog().getWindow().setSoftInputMode(SOFT_INPUT_STATE_VISIBLE);
-
-        final EditText editValue = (EditText) root.findViewById(R.id.var_edit_value);
-        editValue.setText(input.getValue());
-
-        final EditText editDescription = (EditText) root.findViewById(R.id.var_edit_description);
-        editDescription.setText(input.getDescription());
-
-        final OldVar.Builder varBuilder;
-        final IConstant constant = input.getConstant();
-        if (constant != null) {
-            varBuilder = new OldVar.Builder(constant);
-        } else {
-            varBuilder = new OldVar.Builder();
     }
 
-        root.findViewById(R.id.cancel_button).setOnClickListener(new View.OnClickListener() {
+    private class KeyboardUser implements FloatingKeyboard.User {
+        @NonNull
         @Override
-            public void onClick(View v) {
+        public Context getContext() {
-                dismiss();
+            return getActivity();
-            }
-        });
-
-        root.findViewById(R.id.save_button).setOnClickListener(new VarEditorSaver<IConstant>(varBuilder, constant, root, Locator.getInstance().getEngine().getVariablesRegistry(), this));
-
-        if (constant == null) {
-            // CREATE MODE
-            getDialog().setTitle(R.string.c_var_create_var);
-
-            root.findViewById(R.id.remove_button).setVisibility(View.GONE);
-        } else {
-            // EDIT MODE
-            getDialog().setTitle(R.string.c_var_edit_var);
-
-            root.findViewById(R.id.remove_button).setOnClickListener(MathEntityRemover.newConstantRemover(constant, null, getActivity(), EditVariableFragment.this));
-        }
         }
 
-    private void fillGreekKeyboard(View root, final EditText editName) {
+        @NonNull
-        final TextView greekKeyboardToggle = (TextView) root.findViewById(R.id.var_toggle_greek_keyboard);
-        final ViewGroup greekKeyboard = (ViewGroup) root.findViewById(R.id.var_greek_keyboard);
-        greekKeyboardToggle.setPaintFlags(greekKeyboardToggle.getPaintFlags() | UNDERLINE_TEXT_FLAG);
-        greekKeyboardToggle.setOnClickListener(new View.OnClickListener() {
         @Override
-            public void onClick(View v) {
+        public Resources getResources() {
-                if (greekKeyboard.getVisibility() == VISIBLE) {
+            return EditVariableFragment.this.getResources();
-                    greekKeyboard.setVisibility(GONE);
-                    greekKeyboardToggle.setText(R.string.cpp_var_show_greek_keyboard);
-                } else {
-                    greekKeyboard.setVisibility(VISIBLE);
-                    greekKeyboardToggle.setText(R.string.cpp_var_hide_greek_keyboard);
-                }
-            }
-        });
-        LinearLayout keyboardRow = null;
-        final View.OnClickListener buttonOnClickListener = new View.OnClickListener() {
-            @Override
-            public void onClick(View view) {
-                if (!(view instanceof Button)) throw new AssertionError();
-                editName.append(((Button) view).getText());
-            }
-        };
-        for (int i = 0; i < greekAlphabet.length(); i++) {
-            if (i % 5 == 0) {
-                keyboardRow = new LinearLayout(getActivity());
-                keyboardRow.setOrientation(HORIZONTAL);
-                greekKeyboard.addView(keyboardRow, new ViewGroup.LayoutParams(MATCH_PARENT, WRAP_CONTENT));
-            }
-            final Button button = new Button(getActivity());
-            button.setText(String.valueOf(greekAlphabet.charAt(i)));
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
-                fixCapitalization(button);
-            }
-            button.setOnClickListener(buttonOnClickListener);
-            assert keyboardRow != null;
-            keyboardRow.addView(button, new LinearLayout.LayoutParams(0, WRAP_CONTENT, 1F));
-        }
-        final Button button = new Button(getActivity());
-        button.setText("↑");
-        button.setOnClickListener(new View.OnClickListener() {
-            @Override
-            public void onClick(View view) {
-                final boolean upperCase = button.getText().equals("↑");
-                Views.processViewsOfType(greekKeyboard, Button.class, new Views.ViewProcessor<Button>() {
-                    @Override
-                    public void process(@Nonnull Button key) {
-                        final String letter = key.getText().toString();
-                        if (upperCase) {
-                            key.setText(letter.toUpperCase(Locale.US));
-                        } else {
-                            key.setText(letter.toLowerCase(Locale.US));
-                        }
-                    }
-                });
-                if (upperCase) {
-                    button.setText("↓");
-                } else {
-                    button.setText("↑");
-                }
-            }
-        });
-        keyboardRow.addView(button, new LinearLayout.LayoutParams(0, WRAP_CONTENT, 1F));
         }
 
-    @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
+        @NonNull
-    private void fixCapitalization(Button button) {
+        @Override
-        button.setAllCaps(false);
+        public EditText getEditor() {
+            return nameView;
         }
 
-	/*
+        @NonNull
-    **********************************************************************
+        @Override
-	*
+        public ViewGroup getKeyboard() {
-	*                           STATIC
+            return keyboardWindow.getContentView();
-	*
+        }
-	**********************************************************************
-	*/
 
         @Override
-    public void onCalculatorEvent(@Nonnull CalculatorEventData calculatorEventData, @Nonnull CalculatorEventType calculatorEventType, @Nullable Object data) {
+        public void done() {
-        switch (calculatorEventType) {
+            if (keyboardWindow.isShown()) {
-            case constant_removed:
+                keyboardWindow.hide();
-            case constant_added:
-            case constant_changed:
-                if (calculatorEventData.getSource() == this) {
-                    dismiss();
-                }
-                break;
-
             }
+            validateName();
         }
 
-    public static class Input {
+        @Override
-
+        public void showIme() {
-        @Nullable
+            final InputMethodManager keyboard = (InputMethodManager)
-        private IConstant constant;
+                    getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
-
+            keyboard.showSoftInput(getEditor(), InputMethodManager.SHOW_FORCED);
-        @Nullable
+            keyboardWindow.hide();
-        private String name;
-
-        @Nullable
-        private String value;
-
-        @Nullable
-        private String description;
-
-        private Input() {
-        }
-
-        @Nonnull
-        public static Input newInstance() {
-            return new Input();
-        }
-
-        @Nonnull
-        public static Input newFromConstant(@Nonnull IConstant constant) {
-            final Input result = new Input();
-            result.constant = constant;
-            return result;
-        }
-
-        @Nonnull
-        public static Input newFromValue(@Nullable String value) {
-            final Input result = new Input();
-            result.value = value;
-            return result;
-        }
-
-        @Nonnull
-        public static Input newInstance(@Nullable IConstant constant, @Nullable String name, @Nullable String value, @Nullable String description) {
-            final Input result = new Input();
-            result.constant = constant;
-            result.name = name;
-            result.value = value;
-            result.description = description;
-            return result;
-        }
-
-        @Nullable
-        public IConstant getConstant() {
-            return constant;
-        }
-
-        @Nullable
-        public String getName() {
-            return name == null ? (constant == null ? null : constant.getName()) : name;
-        }
-
-        @Nullable
-        public String getValue() {
-            return value == null ? (constant == null ? null : constant.getValue()) : value;
-        }
-
-        @Nullable
-        public String getDescription() {
-            return description == null ? (constant == null ? null : constant.getDescription()) : description;
         }
     }
 }

app/src/main/java/org/solovyev/android/calculator/variables/GreekFloatingKeyboard.java

@@ -0,0 +1,165 @@
+package org.solovyev.android.calculator.variables;
+
+import android.annotation.TargetApi;
+import android.os.Build;
+import android.support.annotation.IdRes;
+import android.support.annotation.NonNull;
+import android.view.HapticFeedbackConstants;
+import android.view.View;
+import android.widget.Button;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+import org.solovyev.android.Views;
+import org.solovyev.android.calculator.R;
+import org.solovyev.android.calculator.keyboard.BaseFloatingKeyboard;
+import org.solovyev.android.calculator.view.EditTextLongClickEraser;
+
+import javax.annotation.Nonnull;
+import java.util.Locale;
+
+
+public class GreekFloatingKeyboard extends BaseFloatingKeyboard implements View.OnClickListener {
+    private final static String GREEK_ALPHABET = "αβγδεζηθικλμνξοπρστυφχψω";
+
+    public GreekFloatingKeyboard(@NonNull User user) {
+        super(user);
+    }
+
+    public void makeView(boolean landscape) {
+        LinearLayout rowView = null;
+        final int columns = getColumnsCount(landscape);
+        final int rows = getRowsCount(landscape);
+        for (int i = 0, letter = 0; i < columns * rows; i++) {
+            final int column = i % columns;
+            final int row = i / columns;
+            if (column == 0) {
+                rowView = makeRow();
+            }
+            if (column == columns - 1) {
+                if (!landscape) {
+                    makeLastColumnPort(rowView, row);
+                } else {
+                    makeLastColumnLand(rowView, row);
+                }
+            } else if (letter < GREEK_ALPHABET.length()) {
+                final Button button = addButton(rowView, View.NO_ID, String.valueOf(GREEK_ALPHABET.charAt(letter)));
+                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
+                    fixCapitalization(button);
+                }
+                letter++;
+            } else {
+                addButton(rowView, View.NO_ID, "");
+            }
+        }
+    }
+
+    private void makeLastColumnLand(@NonNull LinearLayout rowView, int row) {
+        switch (row) {
+            case 0:
+                final View backspace = addImageButton(rowView, R.id.cpp_kb_button_backspace, R.drawable.ic_backspace_white_24dp);
+                EditTextLongClickEraser.attachTo(backspace, user.getEditor());
+                break;
+            case 1:
+                addButton(rowView, R.id.cpp_kb_button_change_case, "↑");
+                break;
+            case 2:
+                addImageButton(rowView, R.id.cpp_kb_button_keyboard, R.drawable.ic_keyboard_white_24dp);
+                break;
+            case 3:
+                addImageButton(rowView, R.id.cpp_kb_button_close, R.drawable.ic_done_white_24dp);
+                break;
+            default:
+                addButton(rowView, View.NO_ID, "");
+                break;
+        }
+    }
+
+    private void makeLastColumnPort(@NonNull LinearLayout rowView, int row) {
+        switch (row) {
+            case 0:
+                addButton(rowView, R.id.cpp_kb_button_clear, "C");
+                break;
+            case 1:
+                final View backspace = addImageButton(rowView, R.id.cpp_kb_button_backspace, R.drawable.ic_backspace_white_24dp);
+                EditTextLongClickEraser.attachTo(backspace, user.getEditor());
+                break;
+            case 2:
+                addButton(rowView, R.id.cpp_kb_button_change_case, "↑");
+                break;
+            case 3:
+                addImageButton(rowView, R.id.cpp_kb_button_keyboard, R.drawable.ic_keyboard_white_24dp);
+                break;
+            case 4:
+                addImageButton(rowView, R.id.cpp_kb_button_close, R.drawable.ic_done_white_24dp);
+                break;
+            default:
+                addButton(rowView, View.NO_ID, "");
+                break;
+        }
+    }
+
+    @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
+    private void fixCapitalization(Button button) {
+        button.setAllCaps(false);
+    }
+
+    protected void fillButton(@NonNull View button, @IdRes int id) {
+        super.fillButton(button, id);
+        button.setOnClickListener(this);
+    }
+
+    public int getRowsCount(boolean landscape) {
+        return landscape ? 4 : 5;
+    }
+
+    public int getColumnsCount(boolean landscape) {
+        return landscape ? 7 : 6;
+    }
+
+    @Override
+    public void onClick(View v) {
+        switch (v.getId()) {
+            case R.id.cpp_kb_button_close:
+                user.done();
+                break;
+            case R.id.cpp_kb_button_change_case:
+                changeCase((Button) v);
+                break;
+            case R.id.cpp_kb_button_keyboard:
+                user.showIme();
+                break;
+            case R.id.cpp_kb_button_clear:
+                user.getEditor().setText("");
+                user.getEditor().setSelection(0);
+                break;
+            default:
+                user.getEditor().append(((TextView) v).getText());
+                break;
+        }
+        user.getEditor().requestFocus();
+        v.performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP);
+    }
+
+    private void changeCase(@NonNull Button button) {
+        final boolean upperCase = button.getText().equals("↑");
+        Views.processViewsOfType(user.getKeyboard(), Button.class, new Views.ViewProcessor<Button>() {
+            @Override
+            public void process(@Nonnull Button key) {
+                final String letter = key.getText().toString();
+                if (!GREEK_ALPHABET.contains(letter.toLowerCase(Locale.US))) {
+                    return;
+                }
+                if (upperCase) {
+                    key.setText(letter.toUpperCase(Locale.US));
+                } else {
+                    key.setText(letter.toLowerCase(Locale.US));
+                }
+            }
+        });
+        if (upperCase) {
+            button.setText("↓");
+        } else {
+            button.setText("↑");
+        }
+    }
+}

app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java

@@ -49,6 +49,7 @@ public class VariablesActivity extends BaseActivity implements CalculatorEventLi
         if (savedInstanceState == null) {
             final Bundle extras = getIntent().getExtras();
             final CppVariable variable = extras != null ? (CppVariable) extras.getParcelable(EXTRA_VARIABLE) : null;
+            EditVariableFragment.showDialog(variable, this);
         }
     }
 

app/src/main/java/org/solovyev/android/calculator/variables/VariablesFragment.java

@@ -47,8 +47,6 @@ import java.util.List;
 
 public class VariablesFragment extends BaseEntitiesFragment<IConstant> implements CalculatorEventListener {
 
-    public static final String ARG_VARIABLE = "variable";
-    public static final String CREATE_VAR_EXTRA_STRING = "create_var";
     @Inject
     VariablesRegistry registry;
     @Inject
@@ -72,25 +70,6 @@ public class VariablesFragment extends BaseEntitiesFragment<IConstant> implement
         }
     }
 
-    @Override
-    public void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-
-        // FIXME: 2016-01-29 continue
-        final Bundle bundle = getArguments();
-        if (bundle != null) {
-            final String varValue = bundle.getString(CREATE_VAR_EXTRA_STRING);
-            if (!Strings.isEmpty(varValue)) {
-                EditVariableFragment.showDialog(EditVariableFragment.Input.newFromValue(varValue), getFragmentManager());
-
-                // in order to stop intent for other tabs
-                bundle.remove(CREATE_VAR_EXTRA_STRING);
-            }
-        }
-
-        setHasOptionsMenu(true);
-    }
-
     @Override
     protected void inject(@Nonnull AppComponent component) {
         super.inject(component);
@@ -106,7 +85,7 @@ public class VariablesFragment extends BaseEntitiesFragment<IConstant> implement
         fab.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
-                EditVariableFragment.showDialog(EditVariableFragment.Input.newInstance(), getFragmentManager());
+                EditVariableFragment.showDialog(null, getFragmentManager());
             }
         });
     }
@@ -116,11 +95,6 @@ public class VariablesFragment extends BaseEntitiesFragment<IConstant> implement
         Locator.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.use_constant, constant);
     }
 
-    @SuppressWarnings({"UnusedDeclaration"})
-    public void addVarButtonClickHandler(@Nonnull View v) {
-        EditVariableFragment.showDialog(EditVariableFragment.Input.newInstance(), this.getActivity().getSupportFragmentManager());
-    }
-
     @Nonnull
     @Override
     protected List<IConstant> getEntities() {
@@ -179,7 +153,7 @@ public class VariablesFragment extends BaseEntitiesFragment<IConstant> implement
                 Locator.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.use_constant, constant);
                 return true;
             case R.string.c_edit:
-                EditVariableFragment.showDialog(EditVariableFragment.Input.newFromConstant(constant), activity.getSupportFragmentManager());
+                EditVariableFragment.showDialog(CppVariable.builder(constant).build(), activity);
                 return true;
             case R.string.c_remove:
                 MathEntityRemover.newConstantRemover(constant, null, activity, activity).showConfirmationDialog();

app/src/main/res/layout/fragment_variable_edit.xml

@@ -0,0 +1,95 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright 2013 serso aka se.solovyev
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~    http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  ~
+  ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+  ~ Contact details
+  ~
+  ~ Email: se.solovyev@gmail.com
+  ~ Site:  http://se.solovyev.org
+  -->
+
+<ScrollView xmlns:a="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    a:layout_width="wrap_content"
+    a:layout_height="wrap_content">
+
+    <LinearLayout
+        a:layout_width="match_parent"
+        a:layout_height="wrap_content"
+        a:orientation="vertical">
+
+        <FrameLayout
+            a:layout_width="match_parent"
+            a:layout_height="wrap_content">
+
+            <android.support.design.widget.TextInputLayout
+                a:id="@+id/variable_name_label"
+                a:layout_width="match_parent"
+                a:layout_height="wrap_content"
+                a:layout_gravity="start|center_vertical">
+
+                <org.solovyev.android.calculator.view.EditTextCompat
+                    a:id="@+id/variable_name"
+                    a:layout_width="match_parent"
+                    a:layout_height="wrap_content"
+                    a:hint="@string/c_var_name"
+                    a:inputType="text" />
+
+            </android.support.design.widget.TextInputLayout>
+
+            <Button
+                a:id="@+id/variable_keyboard_button"
+                a:layout_width="wrap_content"
+                a:layout_height="wrap_content"
+                a:layout_gravity="end|center_vertical"
+                a:background="?attr/selectableItemBackgroundBorderless"
+                a:text="@string/cpp_show_greek_keyboard"
+                a:textAllCaps="false"
+                a:padding="@dimen/cpp_image_button_padding"
+                a:minWidth="0dp"
+                a:textAppearance="?android:attr/textAppearanceSmall"
+                tools:ignore="UnusedAttribute" />
+        </FrameLayout>
+
+        <android.support.design.widget.TextInputLayout
+            a:id="@+id/variable_value_label"
+            a:layout_width="match_parent"
+            a:layout_height="wrap_content">
+
+            <org.solovyev.android.calculator.view.EditTextCompat
+                a:id="@+id/variable_value"
+                a:layout_width="match_parent"
+                a:layout_height="wrap_content"
+                a:hint="@string/c_var_value"
+                a:inputType="numberDecimal" />
+        </android.support.design.widget.TextInputLayout>
+
+        <android.support.design.widget.TextInputLayout
+            a:layout_width="match_parent"
+            a:layout_height="wrap_content">
+
+            <EditText
+                a:id="@+id/variable_description"
+                a:layout_width="match_parent"
+                a:layout_height="wrap_content"
+                a:hint="@string/c_var_description"
+                a:inputType="text" />
+        </android.support.design.widget.TextInputLayout>
+    </LinearLayout>
+
+</ScrollView>
+

app/src/main/res/layout/var_edit.xml

@@ -1,122 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-
-<!--
-  ~ Copyright 2013 serso aka se.solovyev
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~    http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  ~
-  ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-  ~ Contact details
-  ~
-  ~ Email: se.solovyev@gmail.com
-  ~ Site:  http://se.solovyev.org
-  -->
-
-<ScrollView xmlns:a="http://schemas.android.com/apk/res/android"
-    a:layout_width="match_parent"
-    a:layout_height="wrap_content"
-    a:minWidth="300dp">
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:orientation="vertical">
-
-        <TextView
-            style="@style/cpp_default_text_size"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:padding="6dp"
-            a:text="@string/c_var_name" />
-
-        <EditText
-            a:id="@+id/var_edit_name"
-            style="@style/cpp_default_text_size"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:inputType="text" />
-
-        <TextView
-            a:id="@+id/var_toggle_greek_keyboard"
-            style="@style/cpp_default_text_size"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:padding="6dp"
-            a:text="@string/cpp_var_show_greek_keyboard" />
-
-        <LinearLayout
-            a:id="@+id/var_greek_keyboard"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:orientation="vertical"
-            a:visibility="gone" />
-
-        <TextView
-            style="@style/cpp_default_text_size"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:padding="6dp"
-            a:text="@string/c_var_value" />
-
-        <EditText
-            a:id="@+id/var_edit_value"
-            style="@style/cpp_default_text_size"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:inputType="numberDecimal" />
-
-        <TextView
-            style="@style/cpp_default_text_size"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:padding="6dp"
-            a:text="@string/c_var_description" />
-
-        <EditText
-            a:id="@+id/var_edit_description"
-            style="@style/cpp_default_text_size"
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content"
-            a:inputType="text" />
-
-        <LinearLayout
-            a:layout_width="match_parent"
-            a:layout_height="wrap_content">
-
-            <Button
-                a:id="@+id/cancel_button"
-                a:layout_width="0dp"
-                a:layout_height="wrap_content"
-                a:layout_weight="1"
-                a:text="@string/c_cancel" />
-
-            <Button
-                a:id="@+id/remove_button"
-                a:layout_width="0dp"
-                a:layout_height="wrap_content"
-                a:layout_weight="1"
-                a:text="@string/c_remove" />
-
-            <Button
-                a:id="@+id/save_button"
-                a:layout_width="0dp"
-                a:layout_height="wrap_content"
-                a:layout_weight="1"
-                a:text="@string/c_save" />
-
-        </LinearLayout>
-
-    </LinearLayout>
-
-</ScrollView>
-

app/src/main/res/values/ids.xml

@@ -73,5 +73,6 @@
     <item name="cpp_kb_button_functions_constants" type="id" />
     <item name="cpp_kb_button_constants" type="id" />
     <item name="cpp_kb_button_close" type="id" />
+    <item name="cpp_kb_button_change_case" type="id" />
 
 </resources>

app/src/main/res/values/text_strings.xml

@@ -227,6 +227,7 @@
 		several devices.\n\n
 		By clicking \'Continue\' button you will be redirected to the Google Play app to make the payment.</string>
     <string name="cpp_purchase_title">Purchase</string>
+    <string name="cpp_show_greek_keyboard" translatable="false">αβγ</string>
     <string name="cpp_var_show_greek_keyboard">Show Greek letters</string>
     <string name="cpp_var_hide_greek_keyboard">Hide Greek letters</string>
     <string name="cpp_clear_history_title">Clear history?</string>