| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * 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. |
| */ |
| |
| package com.android.server.accessibility; |
| |
| import android.content.Context; |
| import android.os.Handler; |
| import android.os.Message; |
| import android.util.MathUtils; |
| import android.util.Slog; |
| import android.util.TypedValue; |
| import android.view.GestureDetector; |
| import android.view.GestureDetector.SimpleOnGestureListener; |
| import android.view.InputDevice; |
| import android.view.KeyEvent; |
| import android.view.MotionEvent; |
| import android.view.MotionEvent.PointerCoords; |
| import android.view.MotionEvent.PointerProperties; |
| import android.view.ScaleGestureDetector; |
| import android.view.ScaleGestureDetector.OnScaleGestureListener; |
| import android.view.ViewConfiguration; |
| import android.view.accessibility.AccessibilityEvent; |
| |
| /** |
| * This class handles magnification in response to touch events. |
| * |
| * The behavior is as follows: |
| * |
| * 1. Triple tap toggles permanent screen magnification which is magnifying |
| * the area around the location of the triple tap. One can think of the |
| * location of the triple tap as the center of the magnified viewport. |
| * For example, a triple tap when not magnified would magnify the screen |
| * and leave it in a magnified state. A triple tapping when magnified would |
| * clear magnification and leave the screen in a not magnified state. |
| * |
| * 2. Triple tap and hold would magnify the screen if not magnified and enable |
| * viewport dragging mode until the finger goes up. One can think of this |
| * mode as a way to move the magnified viewport since the area around the |
| * moving finger will be magnified to fit the screen. For example, if the |
| * screen was not magnified and the user triple taps and holds the screen |
| * would magnify and the viewport will follow the user's finger. When the |
| * finger goes up the screen will zoom out. If the same user interaction |
| * is performed when the screen is magnified, the viewport movement will |
| * be the same but when the finger goes up the screen will stay magnified. |
| * In other words, the initial magnified state is sticky. |
| * |
| * 3. Pinching with any number of additional fingers when viewport dragging |
| * is enabled, i.e. the user triple tapped and holds, would adjust the |
| * magnification scale which will become the current default magnification |
| * scale. The next time the user magnifies the same magnification scale |
| * would be used. |
| * |
| * 4. When in a permanent magnified state the user can use two or more fingers |
| * to pan the viewport. Note that in this mode the content is panned as |
| * opposed to the viewport dragging mode in which the viewport is moved. |
| * |
| * 5. When in a permanent magnified state the user can use two or more |
| * fingers to change the magnification scale which will become the current |
| * default magnification scale. The next time the user magnifies the same |
| * magnification scale would be used. |
| * |
| * 6. The magnification scale will be persisted in settings and in the cloud. |
| */ |
| class MagnificationGestureHandler implements EventStreamTransformation { |
| private static final String LOG_TAG = "MagnificationEventHandler"; |
| |
| private static final boolean DEBUG_STATE_TRANSITIONS = false; |
| private static final boolean DEBUG_DETECTING = false; |
| private static final boolean DEBUG_PANNING = false; |
| |
| private static final int STATE_DELEGATING = 1; |
| private static final int STATE_DETECTING = 2; |
| private static final int STATE_VIEWPORT_DRAGGING = 3; |
| private static final int STATE_MAGNIFIED_INTERACTION = 4; |
| |
| private static final float MIN_SCALE = 2.0f; |
| private static final float MAX_SCALE = 5.0f; |
| |
| private final MagnificationController mMagnificationController; |
| private final DetectingStateHandler mDetectingStateHandler; |
| private final MagnifiedContentInteractionStateHandler mMagnifiedContentInteractionStateHandler; |
| private final StateViewportDraggingHandler mStateViewportDraggingHandler; |
| |
| |
| private final boolean mDetectControlGestures; |
| |
| private EventStreamTransformation mNext; |
| |
| private int mCurrentState; |
| private int mPreviousState; |
| |
| private boolean mTranslationEnabledBeforePan; |
| |
| private PointerCoords[] mTempPointerCoords; |
| private PointerProperties[] mTempPointerProperties; |
| |
| private long mDelegatingStateDownTime; |
| |
| public MagnificationGestureHandler(Context context, AccessibilityManagerService ams, |
| boolean detectControlGestures) { |
| mMagnificationController = ams.getMagnificationController(); |
| mDetectingStateHandler = new DetectingStateHandler(context); |
| mStateViewportDraggingHandler = new StateViewportDraggingHandler(); |
| mMagnifiedContentInteractionStateHandler = |
| new MagnifiedContentInteractionStateHandler(context); |
| mDetectControlGestures = detectControlGestures; |
| |
| transitionToState(STATE_DETECTING); |
| } |
| |
| @Override |
| public void onMotionEvent(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| if (!event.isFromSource(InputDevice.SOURCE_TOUCHSCREEN)) { |
| if (mNext != null) { |
| mNext.onMotionEvent(event, rawEvent, policyFlags); |
| } |
| return; |
| } |
| if (!mDetectControlGestures) { |
| if (mNext != null) { |
| dispatchTransformedEvent(event, rawEvent, policyFlags); |
| } |
| return; |
| } |
| mMagnifiedContentInteractionStateHandler.onMotionEvent(event, rawEvent, policyFlags); |
| switch (mCurrentState) { |
| case STATE_DELEGATING: { |
| handleMotionEventStateDelegating(event, rawEvent, policyFlags); |
| } |
| break; |
| case STATE_DETECTING: { |
| mDetectingStateHandler.onMotionEvent(event, rawEvent, policyFlags); |
| } |
| break; |
| case STATE_VIEWPORT_DRAGGING: { |
| mStateViewportDraggingHandler.onMotionEvent(event, rawEvent, policyFlags); |
| } |
| break; |
| case STATE_MAGNIFIED_INTERACTION: { |
| // mMagnifiedContentInteractionStateHandler handles events only |
| // if this is the current state since it uses ScaleGestureDetecotr |
| // and a GestureDetector which need well formed event stream. |
| } |
| break; |
| default: { |
| throw new IllegalStateException("Unknown state: " + mCurrentState); |
| } |
| } |
| } |
| |
| @Override |
| public void onKeyEvent(KeyEvent event, int policyFlags) { |
| if (mNext != null) { |
| mNext.onKeyEvent(event, policyFlags); |
| } |
| } |
| |
| @Override |
| public void onAccessibilityEvent(AccessibilityEvent event) { |
| if (mNext != null) { |
| mNext.onAccessibilityEvent(event); |
| } |
| } |
| |
| @Override |
| public void setNext(EventStreamTransformation next) { |
| mNext = next; |
| } |
| |
| @Override |
| public void clearEvents(int inputSource) { |
| if (inputSource == InputDevice.SOURCE_TOUCHSCREEN) { |
| clear(); |
| } |
| |
| if (mNext != null) { |
| mNext.clearEvents(inputSource); |
| } |
| } |
| |
| @Override |
| public void onDestroy() { |
| clear(); |
| } |
| |
| private void clear() { |
| mCurrentState = STATE_DETECTING; |
| mDetectingStateHandler.clear(); |
| mStateViewportDraggingHandler.clear(); |
| mMagnifiedContentInteractionStateHandler.clear(); |
| } |
| |
| private void handleMotionEventStateDelegating(MotionEvent event, |
| MotionEvent rawEvent, int policyFlags) { |
| switch (event.getActionMasked()) { |
| case MotionEvent.ACTION_DOWN: { |
| mDelegatingStateDownTime = event.getDownTime(); |
| } |
| break; |
| case MotionEvent.ACTION_UP: { |
| if (mDetectingStateHandler.mDelayedEventQueue == null) { |
| transitionToState(STATE_DETECTING); |
| } |
| } |
| break; |
| } |
| if (mNext != null) { |
| // We cache some events to see if the user wants to trigger magnification. |
| // If no magnification is triggered we inject these events with adjusted |
| // time and down time to prevent subsequent transformations being confused |
| // by stale events. After the cached events, which always have a down, are |
| // injected we need to also update the down time of all subsequent non cached |
| // events. All delegated events cached and non-cached are delivered here. |
| event.setDownTime(mDelegatingStateDownTime); |
| dispatchTransformedEvent(event, rawEvent, policyFlags); |
| } |
| } |
| |
| private void dispatchTransformedEvent(MotionEvent event, MotionEvent rawEvent, |
| int policyFlags) { |
| // If the event is within the magnified portion of the screen we have |
| // to change its location to be where the user thinks he is poking the |
| // UI which may have been magnified and panned. |
| final float eventX = event.getX(); |
| final float eventY = event.getY(); |
| if (mMagnificationController.isMagnifying() |
| && mMagnificationController.magnifiedRegionContains(eventX, eventY)) { |
| final float scale = mMagnificationController.getScale(); |
| final float scaledOffsetX = mMagnificationController.getOffsetX(); |
| final float scaledOffsetY = mMagnificationController.getOffsetY(); |
| final int pointerCount = event.getPointerCount(); |
| PointerCoords[] coords = getTempPointerCoordsWithMinSize(pointerCount); |
| PointerProperties[] properties = getTempPointerPropertiesWithMinSize( |
| pointerCount); |
| for (int i = 0; i < pointerCount; i++) { |
| event.getPointerCoords(i, coords[i]); |
| coords[i].x = (coords[i].x - scaledOffsetX) / scale; |
| coords[i].y = (coords[i].y - scaledOffsetY) / scale; |
| event.getPointerProperties(i, properties[i]); |
| } |
| event = MotionEvent.obtain(event.getDownTime(), |
| event.getEventTime(), event.getAction(), pointerCount, properties, |
| coords, 0, 0, 1.0f, 1.0f, event.getDeviceId(), 0, event.getSource(), |
| event.getFlags()); |
| } |
| mNext.onMotionEvent(event, rawEvent, policyFlags); |
| } |
| |
| private PointerCoords[] getTempPointerCoordsWithMinSize(int size) { |
| final int oldSize = (mTempPointerCoords != null) ? mTempPointerCoords.length : 0; |
| if (oldSize < size) { |
| PointerCoords[] oldTempPointerCoords = mTempPointerCoords; |
| mTempPointerCoords = new PointerCoords[size]; |
| if (oldTempPointerCoords != null) { |
| System.arraycopy(oldTempPointerCoords, 0, mTempPointerCoords, 0, oldSize); |
| } |
| } |
| for (int i = oldSize; i < size; i++) { |
| mTempPointerCoords[i] = new PointerCoords(); |
| } |
| return mTempPointerCoords; |
| } |
| |
| private PointerProperties[] getTempPointerPropertiesWithMinSize(int size) { |
| final int oldSize = (mTempPointerProperties != null) ? mTempPointerProperties.length |
| : 0; |
| if (oldSize < size) { |
| PointerProperties[] oldTempPointerProperties = mTempPointerProperties; |
| mTempPointerProperties = new PointerProperties[size]; |
| if (oldTempPointerProperties != null) { |
| System.arraycopy(oldTempPointerProperties, 0, mTempPointerProperties, 0, |
| oldSize); |
| } |
| } |
| for (int i = oldSize; i < size; i++) { |
| mTempPointerProperties[i] = new PointerProperties(); |
| } |
| return mTempPointerProperties; |
| } |
| |
| private void transitionToState(int state) { |
| if (DEBUG_STATE_TRANSITIONS) { |
| switch (state) { |
| case STATE_DELEGATING: { |
| Slog.i(LOG_TAG, "mCurrentState: STATE_DELEGATING"); |
| } |
| break; |
| case STATE_DETECTING: { |
| Slog.i(LOG_TAG, "mCurrentState: STATE_DETECTING"); |
| } |
| break; |
| case STATE_VIEWPORT_DRAGGING: { |
| Slog.i(LOG_TAG, "mCurrentState: STATE_VIEWPORT_DRAGGING"); |
| } |
| break; |
| case STATE_MAGNIFIED_INTERACTION: { |
| Slog.i(LOG_TAG, "mCurrentState: STATE_MAGNIFIED_INTERACTION"); |
| } |
| break; |
| default: { |
| throw new IllegalArgumentException("Unknown state: " + state); |
| } |
| } |
| } |
| mPreviousState = mCurrentState; |
| mCurrentState = state; |
| } |
| |
| private interface MotionEventHandler { |
| |
| void onMotionEvent(MotionEvent event, MotionEvent rawEvent, int policyFlags); |
| |
| void clear(); |
| } |
| |
| /** |
| * This class determines if the user is performing a scale or pan gesture. |
| */ |
| private final class MagnifiedContentInteractionStateHandler extends SimpleOnGestureListener |
| implements OnScaleGestureListener, MotionEventHandler { |
| |
| private final ScaleGestureDetector mScaleGestureDetector; |
| |
| private final GestureDetector mGestureDetector; |
| |
| private final float mScalingThreshold; |
| |
| private float mInitialScaleFactor = -1; |
| |
| private boolean mScaling; |
| |
| public MagnifiedContentInteractionStateHandler(Context context) { |
| final TypedValue scaleValue = new TypedValue(); |
| context.getResources().getValue( |
| com.android.internal.R.dimen.config_screen_magnification_scaling_threshold, |
| scaleValue, false); |
| mScalingThreshold = scaleValue.getFloat(); |
| mScaleGestureDetector = new ScaleGestureDetector(context, this); |
| mScaleGestureDetector.setQuickScaleEnabled(false); |
| mGestureDetector = new GestureDetector(context, this); |
| } |
| |
| @Override |
| public void onMotionEvent(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| mScaleGestureDetector.onTouchEvent(event); |
| mGestureDetector.onTouchEvent(event); |
| if (mCurrentState != STATE_MAGNIFIED_INTERACTION) { |
| return; |
| } |
| if (event.getActionMasked() == MotionEvent.ACTION_UP) { |
| clear(); |
| mMagnificationController.persistScale(); |
| if (mPreviousState == STATE_VIEWPORT_DRAGGING) { |
| transitionToState(STATE_VIEWPORT_DRAGGING); |
| } else { |
| transitionToState(STATE_DETECTING); |
| } |
| } |
| } |
| |
| @Override |
| public boolean onScroll(MotionEvent first, MotionEvent second, float distanceX, |
| float distanceY) { |
| if (mCurrentState != STATE_MAGNIFIED_INTERACTION) { |
| return true; |
| } |
| if (DEBUG_PANNING) { |
| Slog.i(LOG_TAG, "Panned content by scrollX: " + distanceX |
| + " scrollY: " + distanceY); |
| } |
| mMagnificationController.offsetMagnifiedRegionCenter(distanceX, distanceY); |
| return true; |
| } |
| |
| @Override |
| public boolean onScale(ScaleGestureDetector detector) { |
| if (!mScaling) { |
| if (mInitialScaleFactor < 0) { |
| mInitialScaleFactor = detector.getScaleFactor(); |
| } else { |
| final float deltaScale = detector.getScaleFactor() - mInitialScaleFactor; |
| if (Math.abs(deltaScale) > mScalingThreshold) { |
| mScaling = true; |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| final float initialScale = mMagnificationController.getScale(); |
| final float targetScale = initialScale * detector.getScaleFactor(); |
| |
| // Don't allow a gesture to move the user further outside the |
| // desired bounds for gesture-controlled scaling. |
| final float scale; |
| if (targetScale > MAX_SCALE && targetScale > initialScale) { |
| // The target scale is too big and getting bigger. |
| scale = MAX_SCALE; |
| } else if (targetScale < MIN_SCALE && targetScale < initialScale) { |
| // The target scale is too small and getting smaller. |
| scale = MIN_SCALE; |
| } else { |
| // The target scale may be outside our bounds, but at least |
| // it's moving in the right direction. This avoids a "jump" if |
| // we're at odds with some other service's desired bounds. |
| scale = targetScale; |
| } |
| |
| final float pivotX = detector.getFocusX(); |
| final float pivotY = detector.getFocusY(); |
| mMagnificationController.setScale(scale, pivotX, pivotY, false); |
| return true; |
| } |
| |
| @Override |
| public boolean onScaleBegin(ScaleGestureDetector detector) { |
| return (mCurrentState == STATE_MAGNIFIED_INTERACTION); |
| } |
| |
| @Override |
| public void onScaleEnd(ScaleGestureDetector detector) { |
| clear(); |
| } |
| |
| @Override |
| public void clear() { |
| mInitialScaleFactor = -1; |
| mScaling = false; |
| } |
| } |
| |
| /** |
| * This class handles motion events when the event dispatcher has |
| * determined that the user is performing a single-finger drag of the |
| * magnification viewport. |
| */ |
| private final class StateViewportDraggingHandler implements MotionEventHandler { |
| |
| private boolean mLastMoveOutsideMagnifiedRegion; |
| |
| @Override |
| public void onMotionEvent(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| final int action = event.getActionMasked(); |
| switch (action) { |
| case MotionEvent.ACTION_DOWN: { |
| throw new IllegalArgumentException("Unexpected event type: ACTION_DOWN"); |
| } |
| case MotionEvent.ACTION_POINTER_DOWN: { |
| clear(); |
| transitionToState(STATE_MAGNIFIED_INTERACTION); |
| } |
| break; |
| case MotionEvent.ACTION_MOVE: { |
| if (event.getPointerCount() != 1) { |
| throw new IllegalStateException("Should have one pointer down."); |
| } |
| final float eventX = event.getX(); |
| final float eventY = event.getY(); |
| if (mMagnificationController.magnifiedRegionContains(eventX, eventY)) { |
| if (mLastMoveOutsideMagnifiedRegion) { |
| mLastMoveOutsideMagnifiedRegion = false; |
| mMagnificationController.setCenter(eventX, |
| eventY, true); |
| } else { |
| mMagnificationController.setCenter(eventX, |
| eventY, false); |
| } |
| } else { |
| mLastMoveOutsideMagnifiedRegion = true; |
| } |
| } |
| break; |
| case MotionEvent.ACTION_UP: { |
| if (!mTranslationEnabledBeforePan) { |
| mMagnificationController.reset(true); |
| } |
| clear(); |
| transitionToState(STATE_DETECTING); |
| } |
| break; |
| case MotionEvent.ACTION_POINTER_UP: { |
| throw new IllegalArgumentException( |
| "Unexpected event type: ACTION_POINTER_UP"); |
| } |
| } |
| } |
| |
| @Override |
| public void clear() { |
| mLastMoveOutsideMagnifiedRegion = false; |
| } |
| } |
| |
| /** |
| * This class handles motion events when the event dispatch has not yet |
| * determined what the user is doing. It watches for various tap events. |
| */ |
| private final class DetectingStateHandler implements MotionEventHandler { |
| |
| private static final int MESSAGE_ON_ACTION_TAP_AND_HOLD = 1; |
| |
| private static final int MESSAGE_TRANSITION_TO_DELEGATING_STATE = 2; |
| |
| private static final int ACTION_TAP_COUNT = 3; |
| |
| private final int mTapTimeSlop = ViewConfiguration.getJumpTapTimeout(); |
| |
| private final int mMultiTapTimeSlop; |
| |
| private final int mTapDistanceSlop; |
| |
| private final int mMultiTapDistanceSlop; |
| |
| private MotionEventInfo mDelayedEventQueue; |
| |
| private MotionEvent mLastDownEvent; |
| |
| private MotionEvent mLastTapUpEvent; |
| |
| private int mTapCount; |
| |
| public DetectingStateHandler(Context context) { |
| mMultiTapTimeSlop = ViewConfiguration.getDoubleTapTimeout() |
| + context.getResources().getInteger( |
| com.android.internal.R.integer.config_screen_magnification_multi_tap_adjustment); |
| mTapDistanceSlop = ViewConfiguration.get(context).getScaledTouchSlop(); |
| mMultiTapDistanceSlop = ViewConfiguration.get(context).getScaledDoubleTapSlop(); |
| } |
| |
| private final Handler mHandler = new Handler() { |
| @Override |
| public void handleMessage(Message message) { |
| final int type = message.what; |
| switch (type) { |
| case MESSAGE_ON_ACTION_TAP_AND_HOLD: { |
| MotionEvent event = (MotionEvent) message.obj; |
| final int policyFlags = message.arg1; |
| onActionTapAndHold(event, policyFlags); |
| } |
| break; |
| case MESSAGE_TRANSITION_TO_DELEGATING_STATE: { |
| transitionToState(STATE_DELEGATING); |
| sendDelayedMotionEvents(); |
| clear(); |
| } |
| break; |
| default: { |
| throw new IllegalArgumentException("Unknown message type: " + type); |
| } |
| } |
| } |
| }; |
| |
| @Override |
| public void onMotionEvent(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| cacheDelayedMotionEvent(event, rawEvent, policyFlags); |
| final int action = event.getActionMasked(); |
| switch (action) { |
| case MotionEvent.ACTION_DOWN: { |
| mHandler.removeMessages(MESSAGE_TRANSITION_TO_DELEGATING_STATE); |
| if (!mMagnificationController.magnifiedRegionContains( |
| event.getX(), event.getY())) { |
| transitionToDelegatingStateAndClear(); |
| return; |
| } |
| if (mTapCount == ACTION_TAP_COUNT - 1 && mLastDownEvent != null |
| && GestureUtils.isMultiTap(mLastDownEvent, event, |
| mMultiTapTimeSlop, mMultiTapDistanceSlop, 0)) { |
| Message message = mHandler.obtainMessage(MESSAGE_ON_ACTION_TAP_AND_HOLD, |
| policyFlags, 0, event); |
| mHandler.sendMessageDelayed(message, |
| ViewConfiguration.getLongPressTimeout()); |
| } else if (mTapCount < ACTION_TAP_COUNT) { |
| Message message = mHandler.obtainMessage( |
| MESSAGE_TRANSITION_TO_DELEGATING_STATE); |
| mHandler.sendMessageDelayed(message, mMultiTapTimeSlop); |
| } |
| clearLastDownEvent(); |
| mLastDownEvent = MotionEvent.obtain(event); |
| } |
| break; |
| case MotionEvent.ACTION_POINTER_DOWN: { |
| if (mMagnificationController.isMagnifying()) { |
| transitionToState(STATE_MAGNIFIED_INTERACTION); |
| clear(); |
| } else { |
| transitionToDelegatingStateAndClear(); |
| } |
| } |
| break; |
| case MotionEvent.ACTION_MOVE: { |
| if (mLastDownEvent != null && mTapCount < ACTION_TAP_COUNT - 1) { |
| final double distance = GestureUtils.computeDistance(mLastDownEvent, |
| event, 0); |
| if (Math.abs(distance) > mTapDistanceSlop) { |
| transitionToDelegatingStateAndClear(); |
| } |
| } |
| } |
| break; |
| case MotionEvent.ACTION_UP: { |
| if (mLastDownEvent == null) { |
| return; |
| } |
| mHandler.removeMessages(MESSAGE_ON_ACTION_TAP_AND_HOLD); |
| if (!mMagnificationController.magnifiedRegionContains( |
| event.getX(), event.getY())) { |
| transitionToDelegatingStateAndClear(); |
| return; |
| } |
| if (!GestureUtils.isTap(mLastDownEvent, event, mTapTimeSlop, |
| mTapDistanceSlop, 0)) { |
| transitionToDelegatingStateAndClear(); |
| return; |
| } |
| if (mLastTapUpEvent != null && !GestureUtils.isMultiTap(mLastTapUpEvent, |
| event, mMultiTapTimeSlop, mMultiTapDistanceSlop, 0)) { |
| transitionToDelegatingStateAndClear(); |
| return; |
| } |
| mTapCount++; |
| if (DEBUG_DETECTING) { |
| Slog.i(LOG_TAG, "Tap count:" + mTapCount); |
| } |
| if (mTapCount == ACTION_TAP_COUNT) { |
| clear(); |
| onActionTap(event, policyFlags); |
| return; |
| } |
| clearLastTapUpEvent(); |
| mLastTapUpEvent = MotionEvent.obtain(event); |
| } |
| break; |
| case MotionEvent.ACTION_POINTER_UP: { |
| /* do nothing */ |
| } |
| break; |
| } |
| } |
| |
| @Override |
| public void clear() { |
| mHandler.removeMessages(MESSAGE_ON_ACTION_TAP_AND_HOLD); |
| mHandler.removeMessages(MESSAGE_TRANSITION_TO_DELEGATING_STATE); |
| clearTapDetectionState(); |
| clearDelayedMotionEvents(); |
| } |
| |
| private void clearTapDetectionState() { |
| mTapCount = 0; |
| clearLastTapUpEvent(); |
| clearLastDownEvent(); |
| } |
| |
| private void clearLastTapUpEvent() { |
| if (mLastTapUpEvent != null) { |
| mLastTapUpEvent.recycle(); |
| mLastTapUpEvent = null; |
| } |
| } |
| |
| private void clearLastDownEvent() { |
| if (mLastDownEvent != null) { |
| mLastDownEvent.recycle(); |
| mLastDownEvent = null; |
| } |
| } |
| |
| private void cacheDelayedMotionEvent(MotionEvent event, MotionEvent rawEvent, |
| int policyFlags) { |
| MotionEventInfo info = MotionEventInfo.obtain(event, rawEvent, |
| policyFlags); |
| if (mDelayedEventQueue == null) { |
| mDelayedEventQueue = info; |
| } else { |
| MotionEventInfo tail = mDelayedEventQueue; |
| while (tail.mNext != null) { |
| tail = tail.mNext; |
| } |
| tail.mNext = info; |
| } |
| } |
| |
| private void sendDelayedMotionEvents() { |
| while (mDelayedEventQueue != null) { |
| MotionEventInfo info = mDelayedEventQueue; |
| mDelayedEventQueue = info.mNext; |
| MagnificationGestureHandler.this.onMotionEvent(info.mEvent, info.mRawEvent, |
| info.mPolicyFlags); |
| info.recycle(); |
| } |
| } |
| |
| private void clearDelayedMotionEvents() { |
| while (mDelayedEventQueue != null) { |
| MotionEventInfo info = mDelayedEventQueue; |
| mDelayedEventQueue = info.mNext; |
| info.recycle(); |
| } |
| } |
| |
| private void transitionToDelegatingStateAndClear() { |
| transitionToState(STATE_DELEGATING); |
| sendDelayedMotionEvents(); |
| clear(); |
| } |
| |
| private void onActionTap(MotionEvent up, int policyFlags) { |
| if (DEBUG_DETECTING) { |
| Slog.i(LOG_TAG, "onActionTap()"); |
| } |
| |
| if (!mMagnificationController.isMagnifying()) { |
| final float targetScale = mMagnificationController.getPersistedScale(); |
| final float scale = MathUtils.constrain(targetScale, MIN_SCALE, MAX_SCALE); |
| mMagnificationController.setScaleAndCenter(scale, up.getX(), up.getY(), true); |
| } else { |
| mMagnificationController.reset(true); |
| } |
| } |
| |
| private void onActionTapAndHold(MotionEvent down, int policyFlags) { |
| if (DEBUG_DETECTING) { |
| Slog.i(LOG_TAG, "onActionTapAndHold()"); |
| } |
| |
| clear(); |
| mTranslationEnabledBeforePan = mMagnificationController.isMagnifying(); |
| |
| final float targetScale = mMagnificationController.getPersistedScale(); |
| final float scale = MathUtils.constrain(targetScale, MIN_SCALE, MAX_SCALE); |
| mMagnificationController.setScaleAndCenter(scale, down.getX(), down.getY(), true); |
| |
| transitionToState(STATE_VIEWPORT_DRAGGING); |
| } |
| } |
| |
| private static final class MotionEventInfo { |
| |
| private static final int MAX_POOL_SIZE = 10; |
| |
| private static final Object sLock = new Object(); |
| |
| private static MotionEventInfo sPool; |
| |
| private static int sPoolSize; |
| |
| private MotionEventInfo mNext; |
| |
| private boolean mInPool; |
| |
| public MotionEvent mEvent; |
| |
| public MotionEvent mRawEvent; |
| |
| public int mPolicyFlags; |
| |
| public static MotionEventInfo obtain(MotionEvent event, MotionEvent rawEvent, |
| int policyFlags) { |
| synchronized (sLock) { |
| MotionEventInfo info; |
| if (sPoolSize > 0) { |
| sPoolSize--; |
| info = sPool; |
| sPool = info.mNext; |
| info.mNext = null; |
| info.mInPool = false; |
| } else { |
| info = new MotionEventInfo(); |
| } |
| info.initialize(event, rawEvent, policyFlags); |
| return info; |
| } |
| } |
| |
| private void initialize(MotionEvent event, MotionEvent rawEvent, |
| int policyFlags) { |
| mEvent = MotionEvent.obtain(event); |
| mRawEvent = MotionEvent.obtain(rawEvent); |
| mPolicyFlags = policyFlags; |
| } |
| |
| public void recycle() { |
| synchronized (sLock) { |
| if (mInPool) { |
| throw new IllegalStateException("Already recycled."); |
| } |
| clear(); |
| if (sPoolSize < MAX_POOL_SIZE) { |
| sPoolSize++; |
| mNext = sPool; |
| sPool = this; |
| mInPool = true; |
| } |
| } |
| } |
| |
| private void clear() { |
| mEvent.recycle(); |
| mEvent = null; |
| mRawEvent.recycle(); |
| mRawEvent = null; |
| mPolicyFlags = 0; |
| } |
| } |
| } |