Fix double tap shift key enable/disable shift locked mode

Bug: 5942452
Change-Id: I2c7b1605bceac2b2f929cd4d97c417ef15c6f754

4 files changed, 80 insertions, 109 deletions

diff --git a/java/src/com/android/inputmethod/keyboard/KeyboardSwitcher.java b/java/src/com/android/inputmethod/keyboard/KeyboardSwitcher.java
index 17ad45df0..d5ea76a2f 100644
--- a/java/src/com/android/inputmethod/keyboard/KeyboardSwitcher.java
+++ b/java/src/com/android/inputmethod/keyboard/KeyboardSwitcher.java
@@ -27,6 +27,7 @@ import android.view.View;
 import android.view.inputmethod.EditorInfo;
 
 import com.android.inputmethod.accessibility.AccessibleKeyboardViewProxy;
+import com.android.inputmethod.keyboard.PointerTracker.TimerProxy;
 import com.android.inputmethod.keyboard.internal.KeyboardState;
 import com.android.inputmethod.latin.DebugSettings;
 import com.android.inputmethod.latin.InputView;
@@ -270,6 +271,24 @@ public class KeyboardSwitcher implements KeyboardState.SwitchActions,
         mState.onUpdateShiftState(mInputMethodService.getCurrentAutoCapsState());
     }
 
+    // Implements {@link KeyboardState.SwitchActions}.
+    @Override
+    public void startDoubleTapTimer() {
+        final LatinKeyboardView keyboardView = getKeyboardView();
+        if (keyboardView != null) {
+            final TimerProxy timer = keyboardView.getTimerProxy();
+            timer.startDoubleTapTimer();
+        }
+    }
+
+    // Implements {@link KeyboardState.SwitchActions}.
+    @Override
+    public boolean isInDoubleTapTimeout() {
+        final LatinKeyboardView keyboardView = getKeyboardView();
+        return (keyboardView != null)
+                ? keyboardView.getTimerProxy().isInDoubleTapTimeout() : false;
+    }
+
     public boolean isInMomentarySwitchState() {
         return mState.isInMomentarySwitchState();
     }
diff --git a/java/src/com/android/inputmethod/keyboard/LatinKeyboardView.java b/java/src/com/android/inputmethod/keyboard/LatinKeyboardView.java
index 056aa255d..5aad67d49 100644
--- a/java/src/com/android/inputmethod/keyboard/LatinKeyboardView.java
+++ b/java/src/com/android/inputmethod/keyboard/LatinKeyboardView.java
@@ -29,7 +29,6 @@ import android.os.Message;
 import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.util.Log;
-import android.view.GestureDetector;
 import android.view.LayoutInflater;
 import android.view.MotionEvent;
 import android.view.View;
@@ -64,8 +63,6 @@ public class LatinKeyboardView extends KeyboardView implements PointerTracker.Ke
         SuddenJumpingTouchEventHandler.ProcessMotionEvent {
     private static final String TAG = LatinKeyboardView.class.getSimpleName();
 
-    private static final boolean ENABLE_CAPSLOCK_BY_DOUBLETAP = true;
-
     // TODO: Kill process when the usability study mode was changed.
     private static final boolean ENABLE_USABILITY_STUDY_LOG = LatinImeLogger.sUsabilityStudy;
 
@@ -111,16 +108,13 @@ public class LatinKeyboardView extends KeyboardView implements PointerTracker.Ke
     private int mOldPointerCount = 1;
     private Key mOldKey;
 
-    // To detect double tap.
-    protected GestureDetector mGestureDetector;
-
     private final KeyTimerHandler mKeyTimerHandler;
 
     private static class KeyTimerHandler extends StaticInnerHandlerWrapper<LatinKeyboardView>
             implements TimerProxy {
         private static final int MSG_REPEAT_KEY = 1;
         private static final int MSG_LONGPRESS_KEY = 2;
-        private static final int MSG_IGNORE_DOUBLE_TAP = 3;
+        private static final int MSG_DOUBLE_TAP = 3;
         private static final int MSG_KEY_TYPED = 4;
 
         private final int mKeyRepeatInterval;
@@ -184,70 +178,24 @@ public class LatinKeyboardView extends KeyboardView implements PointerTracker.Ke
         }
 
         @Override
-        public void cancelKeyTimers() {
-            cancelKeyRepeatTimer();
-            cancelLongPressTimer();
-            removeMessages(MSG_IGNORE_DOUBLE_TAP);
-        }
-
-        public void startIgnoringDoubleTap() {
-            sendMessageDelayed(obtainMessage(MSG_IGNORE_DOUBLE_TAP),
+        public void startDoubleTapTimer() {
+            sendMessageDelayed(obtainMessage(MSG_DOUBLE_TAP),
                     ViewConfiguration.getDoubleTapTimeout());
         }
 
-        public boolean isIgnoringDoubleTap() {
-            return hasMessages(MSG_IGNORE_DOUBLE_TAP);
-        }
-
-        public void cancelAllMessages() {
-            cancelKeyTimers();
+        @Override
+        public boolean isInDoubleTapTimeout() {
+            return hasMessages(MSG_DOUBLE_TAP);
         }
-    }
-
-    class DoubleTapListener extends GestureDetector.SimpleOnGestureListener {
-        private boolean mProcessingShiftDoubleTapEvent = false;
 
         @Override
-        public boolean onDoubleTap(MotionEvent firstDown) {
-            final Keyboard keyboard = getKeyboard();
-            if (ENABLE_CAPSLOCK_BY_DOUBLETAP && keyboard.mId.isAlphabetKeyboard()) {
-                final int pointerIndex = firstDown.getActionIndex();
-                final int id = firstDown.getPointerId(pointerIndex);
-                final PointerTracker tracker = PointerTracker.getPointerTracker(
-                        id, LatinKeyboardView.this);
-                final Key key = tracker.getKeyOn((int)firstDown.getX(), (int)firstDown.getY());
-                // If the first down event is on shift key.
-                if (key != null && key.isShift()) {
-                    mProcessingShiftDoubleTapEvent = true;
-                    return true;
-                }
-            }
-            mProcessingShiftDoubleTapEvent = false;
-            return false;
+        public void cancelKeyTimers() {
+            cancelKeyRepeatTimer();
+            cancelLongPressTimer();
         }
 
-        @Override
-        public boolean onDoubleTapEvent(MotionEvent secondTap) {
-            if (mProcessingShiftDoubleTapEvent
-                    && secondTap.getAction() == MotionEvent.ACTION_DOWN) {
-                final MotionEvent secondDown = secondTap;
-                final int pointerIndex = secondDown.getActionIndex();
-                final int id = secondDown.getPointerId(pointerIndex);
-                final PointerTracker tracker = PointerTracker.getPointerTracker(
-                        id, LatinKeyboardView.this);
-                final Key key = tracker.getKeyOn((int)secondDown.getX(), (int)secondDown.getY());
-                // If the second down event is also on shift key.
-                if (key != null && key.isShift()) {
-                    // Detected a double tap on shift key. If we are in the ignoring double tap
-                    // mode, it means we have already turned off caps lock in
-                    // {@link KeyboardSwitcher#onReleaseShift} .
-                    onDoubleTapShiftKey(mKeyTimerHandler.isIgnoringDoubleTap());
-                    return true;
-                }
-                // Otherwise these events should not be handled as double tap.
-                mProcessingShiftDoubleTapEvent = false;
-            }
-            return mProcessingShiftDoubleTapEvent;
+        public void cancelAllMessages() {
+            cancelKeyTimers();
         }
     }
 
@@ -303,11 +251,6 @@ public class LatinKeyboardView extends KeyboardView implements PointerTracker.Ke
 
         mTouchScreenRegulator = new SuddenJumpingTouchEventHandler(getContext(), this);
 
-        final boolean ignoreMultitouch = true;
-        mGestureDetector = new GestureDetector(
-                getContext(), new DoubleTapListener(), null, ignoreMultitouch);
-        mGestureDetector.setIsLongpressEnabled(false);
-
         mHasDistinctMultitouch = context.getPackageManager()
                 .hasSystemFeature(PackageManager.FEATURE_TOUCHSCREEN_MULTITOUCH_DISTINCT);
 
@@ -342,11 +285,6 @@ public class LatinKeyboardView extends KeyboardView implements PointerTracker.Ke
         PointerTracker.setParameters(mPointerTrackerParams);
     }
 
-    public void startIgnoringDoubleTap() {
-        if (ENABLE_CAPSLOCK_BY_DOUBLETAP)
-            mKeyTimerHandler.startIgnoringDoubleTap();
-    }
-
     public void setKeyboardActionListener(KeyboardActionListener listener) {
         mKeyboardActionListener = listener;
         PointerTracker.setKeyboardActionListener(listener);
@@ -451,17 +389,6 @@ public class LatinKeyboardView extends KeyboardView implements PointerTracker.Ke
         return onLongPress(parentKey, tracker);
     }
 
-    private void onDoubleTapShiftKey(final boolean ignore) {
-        // When shift key is double tapped, the first tap is correctly processed as usual tap. And
-        // the second tap is treated as this double tap event, so that we need not mark tracker
-        // calling setAlreadyProcessed() nor remove the tracker from mPointerQueue.
-        if (ignore) {
-            invokeCustomRequest(LatinIME.CODE_HAPTIC_AND_AUDIO_FEEDBACK);
-        } else {
-            invokeCodeInput(Keyboard.CODE_CAPSLOCK);
-        }
-    }
-
     // This default implementation returns a more keys panel.
     protected MoreKeysPanel onCreateMoreKeysPanel(Key parentKey) {
         if (parentKey.mMoreKeys == null)
@@ -595,14 +522,6 @@ public class LatinKeyboardView extends KeyboardView implements PointerTracker.Ke
             return true;
         }
 
-        // Gesture detector must be enabled only when mini-keyboard is not on the screen.
-        if (mMoreKeysPanel == null && mGestureDetector != null
-                && mGestureDetector.onTouchEvent(me)) {
-            PointerTracker.dismissAllKeyPreviews();
-            mKeyTimerHandler.cancelKeyTimers();
-            return true;
-        }
-
         final long eventTime = me.getEventTime();
         final int index = me.getActionIndex();
         final int id = me.getPointerId(index);
diff --git a/java/src/com/android/inputmethod/keyboard/PointerTracker.java b/java/src/com/android/inputmethod/keyboard/PointerTracker.java
index 4dac3474d..fc92a24a6 100644
--- a/java/src/com/android/inputmethod/keyboard/PointerTracker.java
+++ b/java/src/com/android/inputmethod/keyboard/PointerTracker.java
@@ -76,6 +76,8 @@ public class PointerTracker {
         public void startKeyRepeatTimer(long delay, PointerTracker tracker);
         public void startLongPressTimer(long delay, PointerTracker tracker);
         public void cancelLongPressTimer();
+        public void startDoubleTapTimer();
+        public boolean isInDoubleTapTimeout();
         public void cancelKeyTimers();
 
         public static class Adapter implements TimerProxy {
@@ -90,6 +92,10 @@ public class PointerTracker {
             @Override
             public void cancelLongPressTimer() {}
             @Override
+            public void startDoubleTapTimer() {}
+            @Override
+            public boolean isInDoubleTapTimeout() { return false; }
+            @Override
             public void cancelKeyTimers() {}
         }
     }
diff --git a/java/src/com/android/inputmethod/keyboard/internal/KeyboardState.java b/java/src/com/android/inputmethod/keyboard/internal/KeyboardState.java
index 4af4e3cdf..19c644d1f 100644
--- a/java/src/com/android/inputmethod/keyboard/internal/KeyboardState.java
+++ b/java/src/com/android/inputmethod/keyboard/internal/KeyboardState.java
@@ -51,6 +51,9 @@ public class KeyboardState {
          * Request to call back {@link KeyboardState#onUpdateShiftState(boolean)}.
          */
         public void requestUpdatingShiftState();
+
+        public void startDoubleTapTimer();
+        public boolean isInDoubleTapTimeout();
     }
 
     private final SwitchActions mSwitchActions;
@@ -75,6 +78,10 @@ public class KeyboardState {
     private boolean mPrevMainKeyboardWasShiftLocked;
     private boolean mPrevSymbolsKeyboardWasShifted;
 
+    // For handling double tap.
+    private boolean mIsInAlphabetUnshiftedFromShifted;
+    private boolean mIsInDoubleTapShiftKey;
+
     private final SavedKeyboardState mSavedKeyboardState = new SavedKeyboardState();
 
     static class SavedKeyboardState {
@@ -256,8 +263,7 @@ public class KeyboardState {
         mSwitchActions.requestUpdatingShiftState();
     }
 
-    // TODO: Make this method private
-    public void setSymbolsKeyboard() {
+    private void setSymbolsKeyboard() {
         if (DEBUG_ACTION) {
             Log.d(TAG, "setSymbolsKeyboard");
         }
@@ -348,22 +354,35 @@ public class KeyboardState {
 
     private void onPressShift() {
         if (mIsAlphabetMode) {
-            if (mAlphabetShiftState.isShiftLocked()) {
-                // Shift key is pressed while caps lock state, we will treat this state as shifted
-                // caps lock state and mark as if shift key pressed while normal state.
+            mIsInDoubleTapShiftKey = mSwitchActions.isInDoubleTapTimeout();
+            if (!mIsInDoubleTapShiftKey) {
+                // This is first tap.
+                mSwitchActions.startDoubleTapTimer();
+            }
+            if (mIsInDoubleTapShiftKey) {
+                if (mAlphabetShiftState.isManualShifted() || mIsInAlphabetUnshiftedFromShifted) {
+                    // Shift key has been double tapped while in manual shifted or automatic
+                    // shifted state.
+                    setShiftLocked(true);
+                } else {
+                    // Shift key has been double tapped while in normal state. This is the second
+                    // tap to disable shift locked state, so just ignore this.
+                }
+            } else if (mAlphabetShiftState.isShiftLocked()) {
+                // Shift key is pressed while shift locked state, we will treat this state as
+                // shift lock shifted state and mark as if shift key pressed while normal state.
                 setShifted(SHIFT_LOCK_SHIFTED);
                 mShiftKeyState.onPress();
             } else if (mAlphabetShiftState.isAutomaticShifted()) {
-                // Shift key is pressed while automatic temporary upper case, we have to move to
-                // manual temporary upper case.
+                // Shift key is pressed while automatic shifted, we have to move to manual shifted.
                 setShifted(MANUAL_SHIFT);
                 mShiftKeyState.onPress();
             } else if (mAlphabetShiftState.isShiftedOrShiftLocked()) {
-                // In manual upper case state, we just record shift key has been pressing while
+                // In manual shifted state, we just record shift key has been pressing while
                 // shifted state.
                 mShiftKeyState.onPressOnShifted();
             } else {
-                // In base layout, chording or manual temporary upper case mode is started.
+                // In base layout, chording or manual shifted mode is started.
                 setShifted(MANUAL_SHIFT);
                 mShiftKeyState.onPress();
             }
@@ -378,33 +397,40 @@ public class KeyboardState {
     private void onReleaseShift(boolean withSliding) {
         if (mIsAlphabetMode) {
             final boolean isShiftLocked = mAlphabetShiftState.isShiftLocked();
-            if (mShiftKeyState.isChording()) {
+            mIsInAlphabetUnshiftedFromShifted = false;
+            if (mIsInDoubleTapShiftKey) {
+                // Double tap shift key has been handled in {@link #onPressShift}, so that just
+                // ignore this release shift key here.
+                mIsInDoubleTapShiftKey = false;
+            } else if (mShiftKeyState.isChording()) {
                 if (mAlphabetShiftState.isShiftLockShifted()) {
-                    // After chording input while caps lock state.
+                    // After chording input while shift locked state.
                     setShiftLocked(true);
                 } else {
                     // After chording input while normal state.
                     setShifted(UNSHIFT);
                 }
             } else if (mAlphabetShiftState.isShiftLockShifted() && withSliding) {
-                // In caps lock state, shift has been pressed and slid out to other key.
+                // In shift locked state, shift has been pressed and slid out to other key.
                 setShiftLocked(true);
             } else if (isShiftLocked && !mAlphabetShiftState.isShiftLockShifted()
                     && (mShiftKeyState.isPressing() || mShiftKeyState.isPressingOnShifted())
                     && !withSliding) {
                 // Shift has been long pressed, ignore this release.
             } else if (isShiftLocked && !mShiftKeyState.isIgnoring() && !withSliding) {
-                // Shift has been pressed without chording while caps lock state.
+                // Shift has been pressed without chording while shift locked state.
                 setShiftLocked(false);
             } else if (mAlphabetShiftState.isShiftedOrShiftLocked()
                     && mShiftKeyState.isPressingOnShifted() && !withSliding) {
                 // Shift has been pressed without chording while shifted state.
                 setShifted(UNSHIFT);
+                mIsInAlphabetUnshiftedFromShifted = true;
             } else if (mAlphabetShiftState.isManualShiftedFromAutomaticShifted()
                     && mShiftKeyState.isPressing() && !withSliding) {
-                // Shift has been pressed without chording while manual temporary upper case
-                // transited from automatic temporary upper case.
+                // Shift has been pressed without chording while manual shifted transited from
+                // automatic shifted
                 setShifted(UNSHIFT);
+                mIsInAlphabetUnshiftedFromShifted = true;
             }
         } else {
             // In symbol mode, switch back to the previous keyboard mode if the user chords the
@@ -455,10 +481,11 @@ public class KeyboardState {
         if (mIsAlphabetMode && code == Keyboard.CODE_CAPSLOCK) {
             if (mAlphabetShiftState.isShiftLocked()) {
                 setShiftLocked(false);
-                // Shift key is long pressed or double tapped while caps lock state, we will
-                // toggle back to normal state. And mark as if shift key is released.
+                // Shift key is long pressed while shift locked state, we will toggle back to normal
+                // state. And mark as if shift key is released.
                 mShiftKeyState.onRelease();
             } else {
+                // Shift key is long pressed while shift unloked state.
                 setShiftLocked(true);
             }
         }