cpp-131: Long tap on erase button should remove text faster

Fixes #131

android-app/src/main/java/org/solovyev/android/calculator/AndroidCalculator.java

@@ -104,6 +104,11 @@ public class AndroidCalculator implements Calculator, CalculatorEventListener, S
 		return calculator.evaluate(operation, expression, sequenceId);
 	}
 
+	@Override
+	public void setCalculateOnFly(boolean calculateOnFly) {
+		calculator.setCalculateOnFly(calculateOnFly);
+	}
+
 	@Override
 	public boolean isCalculateOnFly() {
 		return calculator.isCalculateOnFly();

android-app/src/main/java/org/solovyev/android/calculator/BaseUi.java

@@ -39,6 +39,7 @@ import org.solovyev.android.calculator.history.CalculatorHistoryState;
 import org.solovyev.android.calculator.history.HistoryDragProcessor;
 import org.solovyev.android.calculator.view.AngleUnitsButton;
 import org.solovyev.android.calculator.view.DragListenerVibrator;
+import org.solovyev.android.calculator.view.LongClickEraser;
 import org.solovyev.android.calculator.view.NumeralBasesButton;
 import org.solovyev.android.calculator.view.ViewsCache;
 import org.solovyev.common.math.Point2d;
@@ -174,6 +175,11 @@ public abstract class BaseUi implements SharedPreferences.OnSharedPreferenceChan
 			angleUnitsButton.setOnDragListener(new DragListenerVibrator(newDragListener(new CalculatorButtons.AngleUnitsChanger(activity), activity), vibrator, preferences));
 		}
 
+		final View eraseButton = getButton(views, R.id.cpp_button_erase);
+		if (eraseButton != null) {
+			LongClickEraser.createAndAttach(eraseButton);
+		}
+
 		clearButton = getButton(views, R.id.cpp_button_clear);
 		if (clearButton != null) {
 			clearButton.setOnDragListener(new DragListenerVibrator(newDragListener(new CalculatorButtons.NumeralBasesChanger(activity), activity), vibrator, preferences));
@@ -292,8 +298,8 @@ public abstract class BaseUi implements SharedPreferences.OnSharedPreferenceChan
 	}
 
 	@Nullable
-	private <T extends DragButton> T getButton(@Nonnull ViewsCache views, int buttonId) {
+	private <V extends View> V getButton(@Nonnull ViewsCache views, int buttonId) {
-		return (T) views.findViewById(buttonId);
+		return (V) views.findViewById(buttonId);
 	}
 
 	@Override

android-app/src/main/java/org/solovyev/android/calculator/CalculatorButton.java

@@ -115,14 +115,12 @@ public enum CalculatorButton {
 	}
 
 	public void onLongClick() {
-		Locator.getInstance().getNotifier().showDebugMessage("Calculator++ Widget", "Button pressed: " + onLongClickText);
 		if (onLongClickText != null) {
 			Locator.getInstance().getKeyboard().buttonPressed(onLongClickText);
 		}
 	}
 
 	public void onClick() {
-		Locator.getInstance().getNotifier().showDebugMessage("Calculator++ Widget", "Button pressed: " + onClickText);
 		Locator.getInstance().getKeyboard().buttonPressed(onClickText);
 	}
 

android-app/src/main/java/org/solovyev/android/calculator/CalculatorKeyboardFragment.java

@@ -24,14 +24,12 @@ package org.solovyev.android.calculator;
 
 import android.content.SharedPreferences;
 import android.os.Bundle;
-import android.preference.PreferenceManager;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.support.v4.app.Fragment;
 
 import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 
 import static org.solovyev.android.calculator.NumeralBaseButtons.toggleNumericDigits;
 import static org.solovyev.android.calculator.Preferences.Gui.hideNumeralBaseDigits;
@@ -47,68 +45,55 @@ import static org.solovyev.android.calculator.model.AndroidCalculatorEngine.Pref
 public class CalculatorKeyboardFragment extends Fragment implements SharedPreferences.OnSharedPreferenceChangeListener {
 
 	@Nonnull
-	private Preferences.Gui.Theme theme;
+	private FragmentUi ui;
-
-	@Nonnull
-	private FragmentUi fragmentHelper;
 
 	@Override
 	public void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
 
-		final SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this.getActivity());
+		final SharedPreferences preferences = App.getPreferences();
 
 		final Preferences.Gui.Layout layout = Preferences.Gui.getLayout(preferences);
 		if (!layout.isOptimized()) {
-			fragmentHelper = CalculatorApplication.getInstance().createFragmentHelper(R.layout.cpp_app_keyboard_mobile);
+			ui = CalculatorApplication.getInstance().createFragmentHelper(R.layout.cpp_app_keyboard_mobile);
 		} else {
-			fragmentHelper = CalculatorApplication.getInstance().createFragmentHelper(R.layout.cpp_app_keyboard);
+			ui = CalculatorApplication.getInstance().createFragmentHelper(R.layout.cpp_app_keyboard);
 		}
 
-		fragmentHelper.onCreate(this);
+		ui.onCreate(this);
 
 		preferences.registerOnSharedPreferenceChangeListener(this);
-
-		theme = Preferences.Gui.theme.getPreferenceNoError(preferences);
-
 	}
 
 	@Override
 	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
-		return fragmentHelper.onCreateView(this, inflater, container);
+		return ui.onCreateView(this, inflater, container);
 	}
 
 	@Override
 	public void onViewCreated(View root, Bundle savedInstanceState) {
 		super.onViewCreated(root, savedInstanceState);
-
+		ui.onViewCreated(this, root);
-		fragmentHelper.onViewCreated(this, root);
 	}
 
 
 	@Override
 	public void onResume() {
 		super.onResume();
-
+		this.ui.onResume(this);
-		this.fragmentHelper.onResume(this);
 	}
 
 	@Override
 	public void onPause() {
-		this.fragmentHelper.onPause(this);
+		this.ui.onPause(this);
-
 		super.onPause();
 	}
 
 	@Override
 	public void onDestroy() {
 		super.onDestroy();
-
+		ui.onDestroy(this);
-		fragmentHelper.onDestroy(this);
+		App.getPreferences().unregisterOnSharedPreferenceChangeListener(this);
-
-		final SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this.getActivity());
-		preferences.unregisterOnSharedPreferenceChangeListener(this);
-
 	}
 
 	@Override
@@ -130,21 +115,5 @@ public class CalculatorKeyboardFragment extends Fragment implements SharedPrefer
 			CalculatorButtons.initMultiplicationButton(getView());
 		}
 	}
-
-
-	@Nullable
-	private static AndroidCalculatorDisplayView getCalculatorDisplayView() {
-		return (AndroidCalculatorDisplayView) Locator.getInstance().getDisplay().getView();
-	}
-
-	@Nonnull
-	private Calculator getCalculator() {
-		return Locator.getInstance().getCalculator();
-	}
-
-	@Nonnull
-	private static CalculatorKeyboard getKeyboard() {
-		return Locator.getInstance().getKeyboard();
-	}
 }
 

android-app/src/main/java/org/solovyev/android/calculator/view/LongClickEraser.java

@@ -0,0 +1,96 @@
+package org.solovyev.android.calculator.view;
+
+import android.view.GestureDetector;
+import android.view.MotionEvent;
+import android.view.View;
+
+import org.solovyev.android.calculator.Calculator;
+import org.solovyev.android.calculator.CalculatorEditor;
+import org.solovyev.android.calculator.Locator;
+
+import javax.annotation.Nonnull;
+
+public final class LongClickEraser implements View.OnTouchListener {
+
+	@Nonnull
+	private final View view;
+
+	@Nonnull
+	private final GestureDetector gestureDetector;
+
+	@Nonnull
+	private final CalculatorEditor editor = Locator.getInstance().getEditor();
+
+	@Nonnull
+	private final Calculator calculator = Locator.getInstance().getCalculator();
+
+	@Nonnull
+	private final Eraser eraser = new Eraser();
+
+	public static void createAndAttach(@Nonnull View view) {
+		view.setOnTouchListener(new LongClickEraser(view));
+	}
+
+	private LongClickEraser(@Nonnull final View view) {
+		this.view = view;
+		this.gestureDetector = new GestureDetector(view.getContext(), new GestureDetector.SimpleOnGestureListener() {
+			public void onLongPress(MotionEvent e) {
+				eraser.start();
+			}
+		});
+	}
+
+	@Override
+	public boolean onTouch(View v, MotionEvent event) {
+		switch (event.getAction()) {
+			case MotionEvent.ACTION_CANCEL:
+			case MotionEvent.ACTION_UP:
+				eraser.stop();
+				break;
+			default:
+				gestureDetector.onTouchEvent(event);
+				break;
+		}
+		return true;
+	}
+
+	private class Eraser implements Runnable {
+		private static final int DELAY = 500;
+		private long delay;
+		private boolean wasCalculatingOnFly;
+		private boolean erasing;
+
+		@Override
+		public void run() {
+			editor.erase();
+			delay = Math.max(50, 2 * delay / 3);
+			view.postDelayed(this, delay);
+		}
+
+		void start() {
+			if (erasing) {
+				stop();
+			}
+			erasing = true;
+			delay = DELAY;
+			wasCalculatingOnFly = calculator.isCalculateOnFly();
+			if (wasCalculatingOnFly) {
+				calculator.setCalculateOnFly(false);
+			}
+			view.removeCallbacks(this);
+			view.post(this);
+		}
+
+		void stop() {
+			view.removeCallbacks(this);
+			if (!erasing) {
+				return;
+			}
+
+			erasing = false;
+			if (wasCalculatingOnFly) {
+				calculator.setCalculateOnFly(true);
+			}
+		}
+	}
+}

core/src/main/java/org/solovyev/android/calculator/Calculator.java

@@ -64,6 +64,8 @@ public interface Calculator extends CalculatorEventContainer, HistoryControl<Cal
 								 @Nonnull String expression,
 								 @Nonnull Long sequenceId);
 
+	void setCalculateOnFly(boolean calculateOnFly);
+
 	boolean isCalculateOnFly();
 
 	/*

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

@@ -207,8 +207,14 @@ public class CalculatorImpl implements Calculator, CalculatorEventListener {
 		Locator.getInstance().getHistory().load();
 	}
 
+	@Override
 	public void setCalculateOnFly(boolean calculateOnFly) {
-		this.calculateOnFly = calculateOnFly;
+		if (this.calculateOnFly != calculateOnFly) {
+			this.calculateOnFly = calculateOnFly;
+			if (this.calculateOnFly) {
+				evaluate();
+			}
+		}
 	}
 
 	@Override

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

@@ -169,7 +169,7 @@ public enum CalculatorSpecialButton {
 	};
 
 	@Nonnull
-	private static Map<String, CalculatorSpecialButton> buttonsByActionCodes = new HashMap<String, CalculatorSpecialButton>();
+	private static Map<String, CalculatorSpecialButton> buttonsByActionCodes = new HashMap<>();
 
 	@Nonnull
 	private final String actionCode;