content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java - Issue 128613003: [Tracking Patch] Unified gesture detection

Unified Diff: content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java

Issue 128613003: [Tracking Patch] Unified gesture detection (Closed) Base URL: https://chromium.googlesource.com/chromium/src.git@master

Patch Set: Another lonely rebase Created 6 years, 10 months ago

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Index: content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java

diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java

deleted file mode 100644

index 92573f4550742e59f064ee6526dd86287a782a46..0000000000000000000000000000000000000000

--- a/content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java

+++ /dev/null

@@ -1,993 +0,0 @@

-// Use of this source code is governed by a BSD-style license that can be

-// found in the LICENSE file.

-package org.chromium.content.browser;

-import android.annotation.TargetApi;

-import android.content.Context;

-import android.os.Build;

-import android.os.Bundle;

-import android.os.SystemClock;

-import android.util.Log;

-import android.view.InputDevice;

-import android.view.MotionEvent;

-import android.view.ScaleGestureDetector;

-import android.view.ViewConfiguration;

-import org.chromium.base.CommandLine;

-import org.chromium.base.TraceEvent;

-import org.chromium.content.browser.third_party.GestureDetector;

-import org.chromium.content.browser.third_party.GestureDetector.OnDoubleTapListener;

-import org.chromium.content.browser.third_party.GestureDetector.OnGestureListener;

-import org.chromium.content.common.ContentSwitches;

-/**

- * This class handles all MotionEvent handling done in ContentViewCore including the gesture

- * recognition. It sends all related native calls through the interface MotionEventDelegate.

- */

-class ContentViewGestureHandler {

- private static final String TAG = "ContentViewGestureHandler";

- /**

- * Used for FLING_START x velocity

- */

- static final String VELOCITY_X = "Velocity X";

- /**

- * Used for FLING_START y velocity

- */

- static final String VELOCITY_Y = "Velocity Y";

- /**

- * Used for SCROLL_BY x distance (scroll offset of update)

- */

- static final String DISTANCE_X = "Distance X";

- /**

- * Used for SCROLL_BY y distance (scroll offset of update)

- */

- static final String DISTANCE_Y = "Distance Y";

- /**

- * Used for SCROLL_START delta X hint (movement triggering scroll)

- */

- static final String DELTA_HINT_X = "Delta Hint X";

- /**

- * Used for SCROLL_START delta Y hint (movement triggering scroll)

- */

- static final String DELTA_HINT_Y = "Delta Hint Y";

- /**

- * Used in SINGLE_TAP_CONFIRMED to check whether ShowPress has been called before.

- */

- static final String SHOW_PRESS = "ShowPress";

- /**

- * Used for PINCH_BY delta

- */

- static final String DELTA = "Delta";

- private final Bundle mExtraParamBundleSingleTap;

- private final Bundle mExtraParamBundleFling;

- private final Bundle mExtraParamBundleScroll;

- private final Bundle mExtraParamBundleScrollStart;

- private final Bundle mExtraParamBundleDoubleTapDragZoom;

- private final Bundle mExtraParamBundlePinchBy;

- private GestureDetector mGestureDetector;

- private OnGestureListener mListener;

- private OnDoubleTapListener mDoubleTapListener;

- private ScaleGestureDetector mMultiTouchDetector;

- private ScaleGestureListener mMultiTouchListener;

- private MotionEvent mCurrentDownEvent;

- private final MotionEventDelegate mMotionEventDelegate;

- // Remember whether onShowPress() is called. If it is not, in onSingleTapConfirmed()

- // we will first show the press state, then trigger the click.

- private boolean mShowPressIsCalled;

- // Whether a sent TAP_DOWN event has yet to be accompanied by a corresponding

- // SINGLE_TAP_UP, SINGLE_TAP_CONFIRMED, TAP_CANCEL or DOUBLE_TAP.

- private boolean mNeedsTapEndingEvent;

- // This flag is used for ignoring the remaining touch events, i.e., All the events until the

- // next ACTION_DOWN. This is automatically set to false on the next ACTION_DOWN.

- private boolean mIgnoreRemainingTouchEvents;

- // TODO(klobag): this is to avoid a bug in GestureDetector. With multi-touch,

- // mAlwaysInTapRegion is not reset. So when the last finger is up, onSingleTapUp()

- // will be mistakenly fired.

- private boolean mIgnoreSingleTap;

- // True from right before we send the first scroll event until the last finger is raised.

- private boolean mTouchScrolling;

- // Used to remove the touch slop from the initial scroll event in a scroll gesture.

- private boolean mSeenFirstScrollEvent;

- private boolean mPinchInProgress = false;

- private static final int DOUBLE_TAP_TIMEOUT = ViewConfiguration.getDoubleTapTimeout();

- // Indicate current double tap mode state.

- private int mDoubleTapMode = DOUBLE_TAP_MODE_NONE;

- // x, y coordinates for an Anchor on double tap drag zoom.

- private float mDoubleTapDragZoomAnchorX;

- private float mDoubleTapDragZoomAnchorY;

- // On double tap this will store the y coordinates of the touch.

- private float mDoubleTapY;

- // Double tap drag zoom sensitive (speed).

- private static final float DOUBLE_TAP_DRAG_ZOOM_SPEED = 0.005f;

- // Used to track the last rawX/Y coordinates for moves. This gives absolute scroll distance.

- // Useful for full screen tracking.

- private float mLastRawX = 0;

- private float mLastRawY = 0;

- // Cache of square of the scaled touch slop so we don't have to calculate it on every touch.

- private int mScaledTouchSlopSquare;

- // Object that keeps track of and updates scroll snapping behavior.

- private final SnapScrollController mSnapScrollController;

- // Used to track the accumulated scroll error over time. This is used to remove the

- // rounding error we introduced by passing integers to webkit.

- private float mAccumulatedScrollErrorX = 0;

- private float mAccumulatedScrollErrorY = 0;

- // The page's viewport and scale sometimes allow us to disable double tap gesture detection,

- // according to the logic in ContentViewCore.onRenderCoordinatesUpdated().

- private boolean mShouldDisableDoubleTap;

- // Keeps track of the last long press event, if we end up opening a context menu, we would need

- // to potentially use the event to send TAP_CANCEL to remove ::active styling

- private MotionEvent mLastLongPressEvent;

- // Whether the click delay should always be disabled by sending clicks for double tap gestures.

- private final boolean mDisableClickDelay;

- private final float mPxToDp;

- static final int DOUBLE_TAP_MODE_NONE = 0;

- static final int DOUBLE_TAP_MODE_DRAG_DETECTION_IN_PROGRESS = 1;

- static final int DOUBLE_TAP_MODE_DRAG_ZOOM = 2;

- static final int DOUBLE_TAP_MODE_DISABLED = 3;

- /**

- * This is an interface to handle MotionEvent related communication with the native side also

- * access some ContentView specific parameters.

- */

- public interface MotionEventDelegate {

- /**

- * Signal the start of gesture detection for the provided {@link MotionEvent}.

- * @param event The {@link MotionEvent} being fed to the gesture detectors.

- */

- public void onTouchEventHandlingBegin(MotionEvent event);

- /**

- * Signal that all gestures for the current {@link MotionEvent} have been dispatched.

- */

- public void onTouchEventHandlingEnd();

- /**

- * Forward a generated event to the client. This will normally be wrapped by

- * calls to {@link #onTouchEventHandlingBegin(MotionEvent)} and

- * {@link #onTouchEventHandlingEnd()}, unless the gesture is generated from

- * a touch timeout, e.g., LONG_PRESS.

- * @param type The type of the gesture event.

- * @param timeMs The time the gesture event occurred at.

- * @param x The x location for the gesture event.

- * @param y The y location for the gesture event.

- * @param extraParams A bundle that holds specific extra parameters for certain gestures.

- * This is read-only and should not be modified in this function.

- * Refer to gesture type definition for more information.

- * @return Whether the gesture was forwarded successfully.

- */

- boolean onGestureEventCreated(int type, long timeMs, int x, int y, Bundle extraParams);

- }

- ContentViewGestureHandler(Context context, MotionEventDelegate delegate) {

- mExtraParamBundleSingleTap = new Bundle();

- mExtraParamBundleFling = new Bundle();

- mExtraParamBundleScroll = new Bundle();

- mExtraParamBundleScrollStart = new Bundle();

- mExtraParamBundleDoubleTapDragZoom = new Bundle();

- mExtraParamBundlePinchBy = new Bundle();

- mMotionEventDelegate = delegate;

- mSnapScrollController = new SnapScrollController(context);

- mPxToDp = 1.0f / context.getResources().getDisplayMetrics().density;

- mDisableClickDelay = CommandLine.isInitialized() &&

- CommandLine.getInstance().hasSwitch(ContentSwitches.DISABLE_CLICK_DELAY);

- initGestureDetectors(context);

- }

- private void initGestureDetectors(final Context context) {

- final int scaledTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();

- mScaledTouchSlopSquare = scaledTouchSlop * scaledTouchSlop;

- try {

- TraceEvent.begin();

- GestureDetector.SimpleOnGestureListener listener =

- new GestureDetector.SimpleOnGestureListener() {

- @Override

- public boolean onDown(MotionEvent e) {

- mShowPressIsCalled = false;

- mIgnoreSingleTap = false;

- mTouchScrolling = false;

- mSeenFirstScrollEvent = false;

- mLastRawX = e.getRawX();

- mLastRawY = e.getRawY();

- mAccumulatedScrollErrorX = 0;

- mAccumulatedScrollErrorY = 0;

- mLastLongPressEvent = null;

- mNeedsTapEndingEvent = false;

- if (sendMotionEventAsGesture(GestureEventType.TAP_DOWN, e, null)) {

- mNeedsTapEndingEvent = true;

- }

- // Return true to indicate that we want to handle touch

- return true;

- }

- @Override

- public boolean onScroll(MotionEvent e1, MotionEvent e2,

- float rawDistanceX, float rawDistanceY) {

- assert e1.getEventTime() <= e2.getEventTime();

- float distanceX = rawDistanceX;

- float distanceY = rawDistanceY;

- if (!mSeenFirstScrollEvent) {

- // Remove the touch slop region from the first scroll event to avoid a

- // jump.

- mSeenFirstScrollEvent = true;

- double distance = Math.sqrt(

- distanceX * distanceX + distanceY * distanceY);

- double epsilon = 1e-3;

- if (distance > epsilon) {

- double ratio = Math.max(0, distance - scaledTouchSlop) / distance;

- distanceX *= ratio;

- distanceY *= ratio;

- }

- mSnapScrollController.updateSnapScrollMode(distanceX, distanceY);

- if (mSnapScrollController.isSnappingScrolls()) {

- if (mSnapScrollController.isSnapHorizontal()) {

- distanceY = 0;

- } else {

- distanceX = 0;

- }

- mLastRawX = e2.getRawX();

- mLastRawY = e2.getRawY();

- if (!mTouchScrolling) {

- sendTapCancelIfNecessary(e1);

- // Note that scroll start hints are in distance traveled, where

- // scroll deltas are in the opposite direction.

- mExtraParamBundleScrollStart.putInt(DELTA_HINT_X, (int) -rawDistanceX);

- mExtraParamBundleScrollStart.putInt(DELTA_HINT_Y, (int) -rawDistanceY);

- assert mExtraParamBundleScrollStart.size() == 2;

- if (sendGesture(GestureEventType.SCROLL_START, e2.getEventTime(),

- (int) e1.getX(), (int) e1.getY(),

- mExtraParamBundleScrollStart)) {

- mTouchScrolling = true;

- }

- // distanceX and distanceY is the scrolling offset since last onScroll.

- // Because we are passing integers to webkit, this could introduce

- // rounding errors. The rounding errors will accumulate overtime.

- // To solve this, we should be adding back the rounding errors each time

- // when we calculate the new offset.

- int x = (int) e2.getX();

- int y = (int) e2.getY();

- int dx = (int) (distanceX + mAccumulatedScrollErrorX);

- int dy = (int) (distanceY + mAccumulatedScrollErrorY);

- mAccumulatedScrollErrorX = distanceX + mAccumulatedScrollErrorX - dx;

- mAccumulatedScrollErrorY = distanceY + mAccumulatedScrollErrorY - dy;

- mExtraParamBundleScroll.putInt(DISTANCE_X, dx);

- mExtraParamBundleScroll.putInt(DISTANCE_Y, dy);

- assert mExtraParamBundleScroll.size() == 2;

- if ((dx | dy) != 0) {

- sendGesture(GestureEventType.SCROLL_BY,

- e2.getEventTime(), x, y, mExtraParamBundleScroll);

- }

- return true;

- }

- @Override

- public boolean onFling(MotionEvent e1, MotionEvent e2,

- float velocityX, float velocityY) {

- assert e1.getEventTime() <= e2.getEventTime();

- if (mSnapScrollController.isSnappingScrolls()) {

- if (mSnapScrollController.isSnapHorizontal()) {

- velocityY = 0;

- } else {

- velocityX = 0;

- }

- fling(e2.getEventTime(), (int) e1.getX(0), (int) e1.getY(0),

- (int) velocityX, (int) velocityY);

- return true;

- }

- @Override

- public void onShowPress(MotionEvent e) {

- mShowPressIsCalled = true;

- sendMotionEventAsGesture(GestureEventType.SHOW_PRESS, e, null);

- }

- @Override

- public boolean onSingleTapUp(MotionEvent e) {

- if (isDistanceBetweenDownAndUpTooLong(e.getRawX(), e.getRawY())) {

- sendTapCancelIfNecessary(e);

- mIgnoreSingleTap = true;

- return true;

- }

- // This is a hack to address the issue where user hovers

- // over a link for longer than DOUBLE_TAP_TIMEOUT, then

- // onSingleTapConfirmed() is not triggered. But we still

- // want to trigger the tap event at UP. So we override

- // onSingleTapUp() in this case. This assumes singleTapUp

- // gets always called before singleTapConfirmed.

- if (!mIgnoreSingleTap) {

- if (e.getEventTime() - e.getDownTime() > DOUBLE_TAP_TIMEOUT) {

- if (sendTapEndingEventAsGesture(

- GestureEventType.SINGLE_TAP_UP, e, null)) {

- mIgnoreSingleTap = true;

- }

- return true;

- } else if (isDoubleTapDisabled() || mDisableClickDelay) {

- // If double tap has been disabled, there is no need to wait

- // for the double tap timeout.

- return onSingleTapConfirmed(e);

- } else {

- // Notify Blink about this tapUp event anyway,

- // when none of the above conditions applied.

- sendMotionEventAsGesture(

- GestureEventType.SINGLE_TAP_UNCONFIRMED, e, null);

- }

- return triggerLongTapIfNeeded(e);

- }

- @Override

- public boolean onSingleTapConfirmed(MotionEvent e) {

- // Long taps in the edges of the screen have their events delayed by

- // ContentViewHolder for tab swipe operations. As a consequence of the delay

- // this method might be called after receiving the up event.

- // These corner cases should be ignored.

- if (mIgnoreSingleTap) return true;

- mExtraParamBundleSingleTap.putBoolean(SHOW_PRESS, mShowPressIsCalled);

- assert mExtraParamBundleSingleTap.size() == 1;

- if (sendTapEndingEventAsGesture(GestureEventType.SINGLE_TAP_CONFIRMED, e,

- mExtraParamBundleSingleTap)) {

- mIgnoreSingleTap = true;

- }

- return true;

- }

- @Override

- public boolean onDoubleTapEvent(MotionEvent e) {

- switch (e.getActionMasked()) {

- case MotionEvent.ACTION_DOWN:

- // Note that this will be called before the corresponding |onDown()|

- // of the same ACTION_DOWN event. Thus, the preceding TAP_DOWN

- // should be cancelled prior to sending a new one (in |onDown()|).

- sendTapCancelIfNecessary(e);

- mDoubleTapDragZoomAnchorX = e.getX();

- mDoubleTapDragZoomAnchorY = e.getY();

- mDoubleTapMode = DOUBLE_TAP_MODE_DRAG_DETECTION_IN_PROGRESS;

- // If a long-press fires during a double-tap, the GestureDetector

- // will stop feeding MotionEvents to |onDoubleTapEvent()|,

- // preventing double-tap drag zoom. Long press detection will be

- // re-enabled on the next ACTION_DOWN.

- mGestureDetector.setIsLongpressEnabled(false);

- break;

- case MotionEvent.ACTION_MOVE:

- if (mDoubleTapMode

- == DOUBLE_TAP_MODE_DRAG_DETECTION_IN_PROGRESS) {

- float distanceX = mDoubleTapDragZoomAnchorX - e.getX();

- float distanceY = mDoubleTapDragZoomAnchorY - e.getY();

- // Begin double tap drag zoom mode if the move distance is

- // further than the threshold.

- if (isDistanceGreaterThanTouchSlop(distanceX, distanceY)) {

- sendTapCancelIfNecessary(e);

- mExtraParamBundleScrollStart.putInt(DELTA_HINT_X,

- (int) -distanceX);

- mExtraParamBundleScrollStart.putInt(DELTA_HINT_Y,

- (int) -distanceY);

- assert mExtraParamBundleScrollStart.size() == 2;

- sendGesture(GestureEventType.SCROLL_START, e.getEventTime(),

- (int) e.getX(), (int) e.getY(),

- mExtraParamBundleScrollStart);

- pinchBegin(e.getEventTime(),

- Math.round(mDoubleTapDragZoomAnchorX),

- Math.round(mDoubleTapDragZoomAnchorY));

- mDoubleTapMode = DOUBLE_TAP_MODE_DRAG_ZOOM;

- }

- } else if (mDoubleTapMode == DOUBLE_TAP_MODE_DRAG_ZOOM) {

- assert mExtraParamBundleDoubleTapDragZoom.isEmpty();

- sendGesture(GestureEventType.SCROLL_BY, e.getEventTime(),

- (int) e.getX(), (int) e.getY(),

- mExtraParamBundleDoubleTapDragZoom);

- float dy = mDoubleTapY - e.getY();

- pinchBy(e.getEventTime(),

- Math.round(mDoubleTapDragZoomAnchorX),

- Math.round(mDoubleTapDragZoomAnchorY),

- (float) Math.pow(dy > 0 ?

- 1.0f - DOUBLE_TAP_DRAG_ZOOM_SPEED :

- 1.0f + DOUBLE_TAP_DRAG_ZOOM_SPEED,

- Math.abs(dy * mPxToDp)));

- }

- break;

- case MotionEvent.ACTION_UP:

- if (mDoubleTapMode != DOUBLE_TAP_MODE_DRAG_ZOOM) {

- // Normal double tap gesture.

- sendTapEndingEventAsGesture(

- GestureEventType.DOUBLE_TAP, e, null);

- }

- endDoubleTapDragIfNecessary(e);

- break;

- case MotionEvent.ACTION_CANCEL:

- sendTapCancelIfNecessary(e);

- endDoubleTapDragIfNecessary(e);

- break;

- default:

- break;

- }

- mDoubleTapY = e.getY();

- return true;

- }

- @Override

- public boolean onLongPress(MotionEvent e) {

- assert !isDoubleTapActive();

- if (isScaleGestureDetectionInProgress()) return false;

- setIgnoreSingleTap(true);

- mLastLongPressEvent = e;

- sendMotionEventAsGesture(GestureEventType.LONG_PRESS, e, null);

- // Returning true puts the GestureDetector in "longpress" mode, disabling

- // further scrolling. This is undesirable, as it is quite common for a

- // longpress gesture to fire on content that won't trigger a context menu.

- return false;

- }

- /**

- * This method inspects the distance between where the user started touching

- * the surface, and where she released. If the points are too far apart, we

- * should assume that the web page has consumed the scroll-events in-between,

- * and as such, this should not be considered a single-tap.

- *

- * We use the Android frameworks notion of how far a touch can wander before

- * we think the user is scrolling.

- *

- * @param x the new x coordinate

- * @param y the new y coordinate

- * @return true if the distance is too long to be considered a single tap

- */

- private boolean isDistanceBetweenDownAndUpTooLong(float x, float y) {

- return isDistanceGreaterThanTouchSlop(mLastRawX - x, mLastRawY - y);

- }

- };

- mListener = listener;

- mDoubleTapListener = listener;

- mGestureDetector = new GestureDetector(context, listener);

- mMultiTouchListener = new ScaleGestureListener();

- mMultiTouchDetector = new ScaleGestureDetector(context, mMultiTouchListener);

- // ScaleGestureDetector's "QuickScale" feature was introduced in KitKat.

- // As ContentViewGestureHandler already implements this feature,

- // explicitly disable it to prevent double-handling of the gesture.

- if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {

- disableQuickScale(mMultiTouchDetector);

- }

- } finally {

- TraceEvent.end();

- }

- private class ScaleGestureListener implements ScaleGestureDetector.OnScaleGestureListener {

- // Completely silence scaling events. Used in WebView when zoom support

- // is turned off.

- private boolean mPermanentlyIgnoreDetectorEvents = false;

- // Whether any pinch zoom event has been sent to native.

- private boolean mPinchEventSent;

- // ScaleGestureDetector previous to 4.2.2 failed to record the touch event time

- // (b/7626515), so we record it manually for synthesizing pinch gestures.

- private long mCurrentEventTime;

- void setCurrentEventTime(long currentEventTime) {

- mCurrentEventTime = currentEventTime;

- }

- private long getEventTime(ScaleGestureDetector detector) {

- // Workaround for b/7626515, fixed in 4.2.2.

- assert mCurrentEventTime != 0;

- assert detector.getEventTime() == 0 || detector.getEventTime() == mCurrentEventTime;

- return mCurrentEventTime;

- }

- boolean getPermanentlyIgnoreDetectorEvents() {

- return mPermanentlyIgnoreDetectorEvents;

- }

- void setPermanentlyIgnoreDetectorEvents(boolean value) {

- // Note that returning false from onScaleBegin / onScale makes the

- // gesture detector not to emit further scaling notifications

- // related to this gesture. Thus, if detector events are enabled in

- // the middle of the gesture, we don't need to do anything.

- mPermanentlyIgnoreDetectorEvents = value;

- }

- @Override

- public boolean onScaleBegin(ScaleGestureDetector detector) {

- if (mPermanentlyIgnoreDetectorEvents) return false;

- mPinchEventSent = false;

- setIgnoreSingleTap(true);

- return true;

- }

- @Override

- public void onScaleEnd(ScaleGestureDetector detector) {

- if (!mPinchEventSent) return;

- pinchEnd(getEventTime(detector));

- mPinchEventSent = false;

- }

- @Override

- public boolean onScale(ScaleGestureDetector detector) {

- if (mPermanentlyIgnoreDetectorEvents) return false;

- // It is possible that pinchBegin() was never called when we reach here.

- // This happens when webkit handles the 2nd touch down event. That causes

- // ContentView to ignore the onScaleBegin() call. And if webkit does not

- // handle the touch move events afterwards, we will face a situation

- // that pinchBy() is called without any pinchBegin().

- // To solve this problem, we call pinchBegin() here if it is never called.

- if (!mPinchEventSent) {

- pinchBegin(getEventTime(detector),

- (int) detector.getFocusX(), (int) detector.getFocusY());

- mPinchEventSent = true;

- }

- pinchBy(getEventTime(detector), (int) detector.getFocusX(), (int) detector.getFocusY(),

- detector.getScaleFactor());

- return true;

- }

- };

- @TargetApi(Build.VERSION_CODES.KITKAT)

- private static void disableQuickScale(ScaleGestureDetector scaleGestureDetector) {

- if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) return;

- scaleGestureDetector.setQuickScaleEnabled(false);

- }

- /**

- * Fling the ContentView from the current position.

- * @param x Fling touch starting position

- * @param y Fling touch starting position

- * @param velocityX Initial velocity of the fling (X) measured in pixels per second.

- * @param velocityY Initial velocity of the fling (Y) measured in pixels per second.

- */

- void fling(long timeMs, int x, int y, int velocityX, int velocityY) {

- if (velocityX == 0 && velocityY == 0) {

- endTouchScrollIfNecessary(timeMs, true);

- return;

- }

- if (!mTouchScrolling) {

- // The native side needs a SCROLL_BEGIN before FLING_START

- // to send the fling to the correct target. Send if it has not sent.

- // The distance traveled in one second is a reasonable scroll start hint.

- mExtraParamBundleScrollStart.putInt(DELTA_HINT_X, velocityX);

- mExtraParamBundleScrollStart.putInt(DELTA_HINT_Y, velocityY);

- assert mExtraParamBundleScrollStart.size() == 2;

- sendGesture(GestureEventType.SCROLL_START, timeMs, x, y, mExtraParamBundleScrollStart);

- }

- endTouchScrollIfNecessary(timeMs, false);

- mExtraParamBundleFling.putInt(VELOCITY_X, velocityX);

- mExtraParamBundleFling.putInt(VELOCITY_Y, velocityY);

- assert mExtraParamBundleFling.size() == 2;

- sendGesture(GestureEventType.FLING_START, timeMs, x, y, mExtraParamBundleFling);

- }

- /**π

- * End DOUBLE_TAP_MODE_DRAG_ZOOM by sending SCROLL_END and PINCH_END events.

- * @param event A hint event that its x, y, and eventTime will be used for the ending events

- * to send. This argument is an optional and can be null.

- */

- private void endDoubleTapDragIfNecessary(MotionEvent event) {

- assert event != null;

- if (!isDoubleTapActive()) return;

- if (mDoubleTapMode == DOUBLE_TAP_MODE_DRAG_ZOOM) {

- pinchEnd(event.getEventTime());

- sendGesture(GestureEventType.SCROLL_END, event.getEventTime(),

- (int) event.getX(), (int) event.getY(), null);

- }

- mDoubleTapMode = DOUBLE_TAP_MODE_NONE;

- updateDoubleTapListener();

- }

- /**

- * Reset touch scroll flag and optionally send a SCROLL_END event if necessary.

- * @param timeMs The time in ms for the event initiating this gesture.

- * @param sendScrollEndEvent Whether to send SCROLL_END event.

- */

- private void endTouchScrollIfNecessary(long timeMs, boolean sendScrollEndEvent) {

- if (!mTouchScrolling) return;

- mTouchScrolling = false;

- if (sendScrollEndEvent) {

- sendGesture(GestureEventType.SCROLL_END, timeMs, 0, 0, null);

- }

- /**

- * @return Whether native is tracking a scroll.

- */

- boolean isNativeScrolling() {

- // TODO(wangxianzhu): Also return true when fling is active once the UI knows exactly when

- // the fling ends.

- return mTouchScrolling;

- }

- /**

- * @return Whether native is tracking a pinch (i.e. between sending PINCH_BEGIN and PINCH_END).

- */

- boolean isNativePinching() {

- return mPinchInProgress;

- }

- /**

- * Starts a pinch gesture.

- * @param timeMs The time in ms for the event initiating this gesture.

- * @param x The x coordinate for the event initiating this gesture.

- * @param y The x coordinate for the event initiating this gesture.

- */

- private void pinchBegin(long timeMs, int x, int y) {

- sendGesture(GestureEventType.PINCH_BEGIN, timeMs, x, y, null);

- }

- /**

- * Pinch by a given percentage.

- * @param timeMs The time in ms for the event initiating this gesture.

- * @param anchorX The x coordinate for the anchor point to be used in pinch.

- * @param anchorY The y coordinate for the anchor point to be used in pinch.

- * @param delta The percentage to pinch by.

- */

- private void pinchBy(long timeMs, int anchorX, int anchorY, float delta) {

- mExtraParamBundlePinchBy.putFloat(DELTA, delta);

- assert mExtraParamBundlePinchBy.size() == 1;

- sendGesture(GestureEventType.PINCH_BY, timeMs, anchorX, anchorY, mExtraParamBundlePinchBy);

- mPinchInProgress = true;

- }

- /**

- * End a pinch gesture.

- * @param timeMs The time in ms for the event initiating this gesture.

- */

- private void pinchEnd(long timeMs) {

- sendGesture(GestureEventType.PINCH_END, timeMs, 0, 0, null);

- mPinchInProgress = false;

- }

- /**

- * Ignore singleTap gestures.

- */

- void setIgnoreSingleTap(boolean value) {

- mIgnoreSingleTap = value;

- }

- /**

- * Cancel the current touch event sequence by sending ACTION_CANCEL and ignore all the

- * subsequent events until the next ACTION_DOWN.

- *

- * One example usecase is stop processing the touch events when showing context popup menu.

- */

- public void setIgnoreRemainingTouchEvents() {

- if (mIgnoreRemainingTouchEvents) return;

- MotionEvent me = obtainActionCancelMotionEvent();

- if (mCurrentDownEvent != null) {

- // Only insert a synthetic event if there's an active touch sequence.

- onTouchEvent(me);

- } else {

- // Otherwise, we still want to reset the gesture detector pipeline

- // (e.g., reset double-tap detection state).

- mGestureDetector.onTouchEvent(me);

- processTouchEventForMultiTouch(me);

- }

- me.recycle();

- assert mCurrentDownEvent == null;

- mIgnoreRemainingTouchEvents = true;

- }

- /**

- * Handle the incoming MotionEvent.

- * @return Whether the event was handled.

- */

- boolean onTouchEvent(MotionEvent event) {

- final int eventAction = event.getActionMasked();

- // Only these actions have any effect on gesture detection. Other

- // actions have no corresponding WebTouchEvent type and may confuse the

- // touch pipline, so we ignore them entirely.

- if (eventAction != MotionEvent.ACTION_DOWN

- && eventAction != MotionEvent.ACTION_UP

- && eventAction != MotionEvent.ACTION_CANCEL

- && eventAction != MotionEvent.ACTION_MOVE

- && eventAction != MotionEvent.ACTION_POINTER_DOWN

- && eventAction != MotionEvent.ACTION_POINTER_UP) {

- return false;

- }

- try {

- TraceEvent.begin("onTouchEvent");

- if (mIgnoreRemainingTouchEvents) {

- if (event.getActionMasked() == MotionEvent.ACTION_DOWN) {

- mIgnoreRemainingTouchEvents = false;

- } else {

- return false;

- }

- return processTouchEvent(event);

- } finally {

- TraceEvent.end("onTouchEvent");

- }

- /**

- * Handle content view losing focus -- ensure that any remaining active state is removed.

- */

- void onWindowFocusLost() {

- // TODO(jdduke): Determine if this should behave more like setIgnoreRemainingTouchEvents().

- if (mLastLongPressEvent != null) {

- sendTapCancelIfNecessary(mLastLongPressEvent);

- }

- private MotionEvent obtainActionCancelMotionEvent() {

- MotionEvent me = MotionEvent.obtain(

- mCurrentDownEvent != null ?

- mCurrentDownEvent.getDownTime() : SystemClock.uptimeMillis(),

- SystemClock.uptimeMillis(),

- MotionEvent.ACTION_CANCEL, 0.0f, 0.0f, 0);

- me.setSource(mCurrentDownEvent != null ?

- mCurrentDownEvent.getSource() : InputDevice.SOURCE_CLASS_POINTER);

- return me;

- }

- /**

- * Resets gesture handlers state; called on didStartLoading().

- * Note that this does NOT clear the pending motion events queue;

- * it gets cleared in hasTouchEventHandlers() called from WebKit

- * FrameLoader::transitionToCommitted iff the page ever had touch handlers.

- */

- void resetGestureHandlers() {

- MotionEvent me = obtainActionCancelMotionEvent();

- mGestureDetector.onTouchEvent(me);

- processTouchEventForMultiTouch(me);

- me.recycle();

- }

- private boolean processTouchEvent(MotionEvent event) {

- if (!canHandle(event)) return false;

- try {

- mMotionEventDelegate.onTouchEventHandlingBegin(event);

- final boolean wasTouchScrolling = mTouchScrolling;

- mSnapScrollController.setSnapScrollingMode(event, isScaleGestureDetectionInProgress());

- if (event.getActionMasked() == MotionEvent.ACTION_POINTER_DOWN) {

- endDoubleTapDragIfNecessary(event);

- } else if (event.getActionMasked() == MotionEvent.ACTION_DOWN) {

- mGestureDetector.setIsLongpressEnabled(true);

- mCurrentDownEvent = MotionEvent.obtain(event);

- }

- boolean handled = mGestureDetector.onTouchEvent(event);

- handled |= processTouchEventForMultiTouch(event);

- if (event.getAction() == MotionEvent.ACTION_UP

- || event.getAction() == MotionEvent.ACTION_CANCEL) {

- if (event.getAction() == MotionEvent.ACTION_CANCEL) {

- sendTapCancelIfNecessary(event);

- }

- // "Last finger raised" could be an end to movement, but it should

- // only terminate scrolling if the event did not cause a fling.

- if (wasTouchScrolling && !handled) {

- endTouchScrollIfNecessary(event.getEventTime(), true);

- }

- if (mCurrentDownEvent != null) recycleEvent(mCurrentDownEvent);

- mCurrentDownEvent = null;

- }

- return handled;

- } finally {

- mMotionEventDelegate.onTouchEventHandlingEnd();

- }

- private boolean isScaleGestureDetectionInProgress() {

- return !mMultiTouchListener.getPermanentlyIgnoreDetectorEvents()

- && mMultiTouchDetector.isInProgress();

- }

- private boolean processTouchEventForMultiTouch(MotionEvent event) {

- // TODO(jdduke): Need to deal with multi-touch transition

- mMultiTouchListener.setCurrentEventTime(event.getEventTime());

- try {

- boolean inGesture = isScaleGestureDetectionInProgress();

- boolean retVal = mMultiTouchDetector.onTouchEvent(event);

- if (!inGesture && (event.getActionMasked() == MotionEvent.ACTION_UP

- || event.getActionMasked() == MotionEvent.ACTION_CANCEL)) {

- return false;

- }

- return retVal;

- } catch (Exception e) {

- Log.e(TAG, "ScaleGestureDetector got into a bad state!", e);

- assert false;

- }

- return false;

- }

- private void recycleEvent(MotionEvent event) {

- event.recycle();

- }

- private boolean sendMotionEventAsGesture(

- int type, MotionEvent event, Bundle extraParams) {

- return sendGesture(type, event.getEventTime(),

- (int) event.getX(), (int) event.getY(), extraParams);

- }

- private boolean sendGesture(

- int type, long timeMs, int x, int y, Bundle extraParams) {

- assert timeMs != 0;

- // The only valid gestures that can occur after the touch sequence has

- // ended are SHOW_PRESS and SINGLE_TAP_CONFIRMED, potentially triggered

- // after the double-tap delay window times out.

- if (mCurrentDownEvent == null

- && type != GestureEventType.SINGLE_TAP_CONFIRMED

- && type != GestureEventType.SHOW_PRESS) {

- return false;

- }

- return mMotionEventDelegate.onGestureEventCreated(type, timeMs, x, y, extraParams);

- }

- private boolean sendTapEndingEventAsGesture(int type, MotionEvent e, Bundle extraParams) {

- if (!sendMotionEventAsGesture(type, e, extraParams)) return false;

- mNeedsTapEndingEvent = false;

- return true;

- }

- private void sendTapCancelIfNecessary(MotionEvent e) {

- if (!mNeedsTapEndingEvent) return;

- if (!sendTapEndingEventAsGesture(GestureEventType.TAP_CANCEL, e, null)) return;

- mLastLongPressEvent = null;

- }

- /**

- * @return Whether the ContentViewGestureHandler can handle a MotionEvent right now. True only

- * if it's the start of a new stream (ACTION_DOWN), or a continuation of the current stream.

- */

- private boolean canHandle(MotionEvent ev) {

- return ev.getAction() == MotionEvent.ACTION_DOWN ||

- (mCurrentDownEvent != null && mCurrentDownEvent.getDownTime() == ev.getDownTime());

- }

- /**

- * @return Whether the event can trigger a LONG_TAP gesture. True when it can and the event

- * will be consumed.

- */

- private boolean triggerLongTapIfNeeded(MotionEvent ev) {

- if (mLastLongPressEvent != null

- && ev.getAction() == MotionEvent.ACTION_UP

- && !isScaleGestureDetectionInProgress()) {

- sendTapCancelIfNecessary(ev);

- sendMotionEventAsGesture(GestureEventType.LONG_TAP, ev, null);

- return true;

- }

- return false;

- }

- /**

- * This is for testing only.

- * Sends a show pressed state gesture through mListener. This should always be called after

- * a down event;

- */

- void sendShowPressedStateGestureForTesting() {

- if (mCurrentDownEvent == null) return;

- mListener.onShowPress(mCurrentDownEvent);

- }

- /**

- * This is for testing only.

- * @return Whether a sent TapDown event has been accompanied by a tap-ending event.

- */

- boolean needsTapEndingEventForTesting() {

- return mNeedsTapEndingEvent;

- }

- /**

- * Update whether multi-touch gestures are supported.

- */

- public void updateMultiTouchSupport(boolean supportsMultiTouchZoom) {

- mMultiTouchListener.setPermanentlyIgnoreDetectorEvents(!supportsMultiTouchZoom);

- }

- /**

- * Update whether double-tap gestures are supported. This allows

- * double-tap gesture suppression independent of whether or not the page's

- * viewport and scale would normally prevent double-tap.

- * Note: This should never be called while a double-tap gesture is in progress.

- * @param supportDoubleTap Whether double-tap gestures are supported.

- */

- public void updateDoubleTapSupport(boolean supportDoubleTap) {

- assert !isDoubleTapActive();

- int doubleTapMode = supportDoubleTap ?

- DOUBLE_TAP_MODE_NONE : DOUBLE_TAP_MODE_DISABLED;

- if (mDoubleTapMode == doubleTapMode) return;

- mDoubleTapMode = doubleTapMode;

- updateDoubleTapListener();

- }

- /**

- * Update whether double-tap gesture detection should be suppressed due to

- * the viewport or scale of the current page. Suppressing double-tap gesture

- * detection allows for rapid and responsive single-tap gestures.

- * @param shouldDisableDoubleTap Whether double-tap should be suppressed.

- */

- public void updateShouldDisableDoubleTap(boolean shouldDisableDoubleTap) {

- if (mShouldDisableDoubleTap == shouldDisableDoubleTap) return;

- mShouldDisableDoubleTap = shouldDisableDoubleTap;

- updateDoubleTapListener();

- }

- /**

- * @return Whether double-tap gesture detection is enabled.

- */

- public boolean isDoubleTapDisabled() {

- return mDoubleTapMode == DOUBLE_TAP_MODE_DISABLED || mShouldDisableDoubleTap;

- }

- /**

- * @return Whether the click delay preceding a double tap is disabled.

- */

- public boolean isClickDelayDisabled() {

- return mDisableClickDelay;

- }

- /**

- * @return Whether a double tap-gesture is in-progress.

- */

- public boolean isDoubleTapActive() {

- return mDoubleTapMode != DOUBLE_TAP_MODE_DISABLED &&

- mDoubleTapMode != DOUBLE_TAP_MODE_NONE;

- }

- private void updateDoubleTapListener() {

- if (isDoubleTapDisabled()) {

- // Defer nulling the DoubleTapListener until the double tap gesture is complete.

- if (isDoubleTapActive()) return;

- mGestureDetector.setOnDoubleTapListener(null);

- } else {

- mGestureDetector.setOnDoubleTapListener(mDoubleTapListener);

- }

- private boolean isDistanceGreaterThanTouchSlop(float distanceX, float distanceY) {

- return distanceX * distanceX + distanceY * distanceY > mScaledTouchSlopSquare;

- }