Example usage for android.view VelocityTracker obtain

List of usage examples for android.view VelocityTracker obtain

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Introduction

In this page you can find the example usage for android.view VelocityTracker obtain.

Prototype

static public VelocityTracker obtain()

Source Link

Document

Retrieve a new VelocityTracker object to watch the velocity of a motion.

Usage

From source file:com.android.kit.swipeback.ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will
 * dispatch callback events as needed before returning. The parent view's
 * onTouchEvent implementation should call this.
 *
 * @param ev The touch event received by the parent view
 *//*from  www. j  a  v a2s  .  c  om*/
public void processTouchEvent(MotionEvent ev) {

    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't get
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        saveInitialMotion(x, y, pointerId);

        final View toCapture = findTopChildUnder((int) x, (int) y);

        // Catch a settling view if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgeTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_JUDGING) {

            final int i = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, i);
            final float y = MotionEventCompat.getY(ev, i);
            final float dx = x - mInitialMotionX[mActivePointerId];
            final float dy = y - mInitialMotionY[mActivePointerId];

            reportNewEdgeDrags(dx, dy, mActivePointerId);
            if (mDragState == STATE_DRAGGING) {
                // Callback might have started an edge drag.
                break;
            }

            final View toCapture = findTopChildUnder((int) x, (int) y);
            int slop = checkTouchSlop(toCapture, dx, dy);
            if (slop == -1)
                cancel();
            else if (slop > 0 && tryCaptureViewForDrag(toCapture, mActivePointerId)) {
                break;
            }
            saveLastMotion(ev);
        }

        if (mDragState == STATE_DRAGGING) {
            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            //????????
            if (index == -1)
                break;

            final float x = MotionEventCompat.getX(ev, index);
            final float y = MotionEventCompat.getY(ev, index);
            final int idx = (int) (x - mLastMotionX[mActivePointerId]);
            final int idy = (int) (y - mLastMotionY[mActivePointerId]);
            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp();
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    }
}

From source file:bw.com.yunifangstore.view.LazyViewPager.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    if (mFakeDragging) {
        // A fake drag is in progress already, ignore this real one
        // but still eat the touch events.
        // (It is likely that the user is multi-touching the screen.)
        return true;
    }//w ww  .java  2  s . c om

    if (ev.getAction() == MotionEvent.ACTION_DOWN && ev.getEdgeFlags() != 0) {
        // Don't handle edge touches immediately -- they may actually belong to one of our
        // descendants.
        return false;
    }

    if (mAdapter == null || mAdapter.getCount() == 0) {
        // Nothing to present or scroll; nothing to touch.
        return false;
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    final int action = ev.getAction();
    boolean needsInvalidate = false;

    switch (action & MotionEventCompat.ACTION_MASK) {
    case MotionEvent.ACTION_DOWN: {
        /*
         * If being flinged and user touches, stop the fling. isFinished
         * will be false if being flinged.
         */
        completeScroll();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        if (!mIsBeingDragged) {
            final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, pointerIndex);
            final float xDiff = Math.abs(x - mLastMotionX);
            final float y = MotionEventCompat.getY(ev, pointerIndex);
            final float yDiff = Math.abs(y - mLastMotionY);
            if (DEBUG)
                Log.v(TAG, "Moved x to " + x + "," + y + " diff=" + xDiff + "," + yDiff);
            if (xDiff > mTouchSlop && xDiff > yDiff) {
                if (DEBUG)
                    Log.v(TAG, "Starting drag!");
                mIsBeingDragged = true;
                mLastMotionX = x;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);
            }
        }
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            final float deltaX = mLastMotionX - x;
            mLastMotionX = x;
            float oldScrollX = getScrollX();
            float scrollX = oldScrollX + deltaX;
            final int width = getWidth();
            final int widthWithMargin = width + mPageMargin;

            final int lastItemIndex = mAdapter.getCount() - 1;
            final float leftBound = Math.max(0, (mCurItem - 1) * widthWithMargin);
            final float rightBound = Math.min(mCurItem + 1, lastItemIndex) * widthWithMargin;
            if (scrollX < leftBound) {
                if (leftBound == 0) {
                    float over = -scrollX;
                    needsInvalidate = mLeftEdge.onPull(over / width);
                }
                scrollX = leftBound;
            } else if (scrollX > rightBound) {
                if (rightBound == lastItemIndex * widthWithMargin) {
                    float over = scrollX - rightBound;
                    needsInvalidate = mRightEdge.onPull(over / width);
                }
                scrollX = rightBound;
            }
            // Don't lose the rounded component
            mLastMotionX += scrollX - (int) scrollX;
            scrollTo((int) scrollX, getScrollY());
            if (mOnPageChangeListener != null) {
                final int position = (int) scrollX / widthWithMargin;
                final int positionOffsetPixels = (int) scrollX % widthWithMargin;
                final float positionOffset = (float) positionOffsetPixels / widthWithMargin;
                mOnPageChangeListener.onPageScrolled(position, positionOffset, positionOffsetPixels);
            }
        }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int widthWithMargin = getWidth() + mPageMargin;
            final int scrollX = getScrollX();
            final int currentPage = scrollX / widthWithMargin;
            int nextPage = initialVelocity > 0 ? currentPage : currentPage + 1;
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            setCurrentItemInternal(mCurItem, true, true);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        final float x = MotionEventCompat.getX(ev, index);
        mLastMotionX = x;
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionX = MotionEventCompat.getX(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        invalidate();
    }
    return false;
}

From source file:com.example.administrator.mouseapp.M5ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will dispatch callback events
 * as needed before returning. The parent view's onTouchEvent implementation should call this.
 *
 * @param ev The touch event received by the parent view
 *///w  w w . j av  a2s. c om
public void processTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't get
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        final View toCapture = findTopChildUnder((int) x, (int) y);

        saveInitialMotion(x, y, pointerId);

        // Since the parent is already directly processing this touch event,
        // there is no reason to delay for a slop before dragging.
        // Start immediately if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgesTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);

        // A ViewDragHelper can only manipulate one view at a time.
        if (mDragState == STATE_IDLE) {
            // If we're idle we can do anything! Treat it like a normal down event.

            final View toCapture = findTopChildUnder((int) x, (int) y);
            tryCaptureViewForDrag(toCapture, pointerId);

            final int edgesTouched = mInitialEdgesTouched[pointerId];
            if ((edgesTouched & mTrackingEdges) != 0) {
                mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
            }
        } else if (isCapturedViewUnder((int) x, (int) y)) {
            // We're still tracking a captured view. If the same view is under this
            // point, we'll swap to controlling it with this pointer instead.
            // (This will still work if we're "catching" a settling view.)

            tryCaptureViewForDrag(mCapturedView, pointerId);
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_DRAGGING) {
            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, index);
            final float y = MotionEventCompat.getY(ev, index);
            float deltaX = x - mLastMotionX[mActivePointerId];
            final int idx = (int) (deltaX < 0 ? deltaX * mResistance[2] : deltaX * mResistance[3]);
            float deltaY = y - mLastMotionY[mActivePointerId];
            final int idy = (int) (deltaY < 0 ? deltaY * mResistance[0] : deltaY * mResistance[1]);

            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);

            saveLastMotion(ev);
        } else {
            // Check to see if any pointer is now over a draggable view.
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int pointerId = MotionEventCompat.getPointerId(ev, i);
                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                final float dx = x - mInitialMotionX[pointerId];
                final float dy = y - mInitialMotionY[pointerId];

                reportNewEdgeDrags(dx, dy, pointerId);
                if (mDragState == STATE_DRAGGING) {
                    // Callback might have started an edge drag.
                    break;
                }

                final View toCapture = findTopChildUnder((int) x, (int) y);
                if (checkTouchSlop(toCapture, dx, dy) && tryCaptureViewForDrag(toCapture, pointerId)) {
                    break;
                }
            }
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
            // Try to find another pointer that's still holding on to the captured view.
            int newActivePointer = INVALID_POINTER;
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int id = MotionEventCompat.getPointerId(ev, i);
                if (id == mActivePointerId) {
                    // This one's going away, skip.
                    continue;
                }

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                if (findTopChildUnder((int) x, (int) y) == mCapturedView
                        && tryCaptureViewForDrag(mCapturedView, id)) {
                    newActivePointer = mActivePointerId;
                    break;
                }
            }

            if (newActivePointer == INVALID_POINTER) {
                // We didn't find another pointer still touching the view, release it.
                releaseViewForPointerUp();
            }
        }
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp();
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    }
}

From source file:cn.edu.bjtu.svnteen.nourriture.uilib.ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will
 * dispatch callback events as needed before returning. The parent view's
 * onTouchEvent implementation should call this.
 * /*  www  .j  ava2  s.c om*/
 * @param ev The touch event received by the parent view
 */
public void processTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't get
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        final View toCapture = findTopChildUnder((int) x, (int) y);

        saveInitialMotion(x, y, pointerId);

        // Since the parent is already directly processing this touch
        // event,
        // there is no reason to delay for a slop before dragging.
        // Start immediately if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgesTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);

        // A ViewDragHelper can only manipulate one view at a time.
        if (mDragState == STATE_IDLE) {
            // If we're idle we can do anything! Treat it like a normal
            // down event.

            final View toCapture = findTopChildUnder((int) x, (int) y);
            tryCaptureViewForDrag(toCapture, pointerId);

            final int edgesTouched = mInitialEdgesTouched[pointerId];
            if ((edgesTouched & mTrackingEdges) != 0) {
                mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
            }
        } else if (isCapturedViewUnder((int) x, (int) y)) {
            // We're still tracking a captured view. If the same view is
            // under this
            // point, we'll swap to controlling it with this pointer
            // instead.
            // (This will still work if we're "catching" a settling
            // view.)

            tryCaptureViewForDrag(mCapturedView, pointerId);
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_DRAGGING) {
            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, index);
            final int idx = (int) (x - mLastMotionX[mActivePointerId]);
            final int idy = 0;

            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);

            saveLastMotion(ev);
        } else {
            // Check to see if any pointer is now over a draggable view.
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int pointerId = MotionEventCompat.getPointerId(ev, i);
                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                final float dx = x - mInitialMotionX[pointerId];
                //final float dy = y - mInitialMotionY[pointerId];
                final int dy = 0; // ???bug????                        // ??????   by huqian

                reportNewEdgeDrags(dx, dy, pointerId);
                if (mDragState == STATE_DRAGGING) {
                    // Callback might have started an edge drag.
                    break;
                }

                final View toCapture = findTopChildUnder((int) x, (int) y);
                if (checkTouchSlop(toCapture, dx, dy) && tryCaptureViewForDrag(toCapture, pointerId)) {
                    break;
                }
            }
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
            // Try to find another pointer that's still holding on to
            // the captured view.
            int newActivePointer = INVALID_POINTER;
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int id = MotionEventCompat.getPointerId(ev, i);
                if (id == mActivePointerId) {
                    // This one's going away, skip.
                    continue;
                }

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                if (findTopChildUnder((int) x, (int) y) == mCapturedView
                        && tryCaptureViewForDrag(mCapturedView, id)) {
                    newActivePointer = mActivePointerId;
                    break;
                }
            }

            if (newActivePointer == INVALID_POINTER) {
                // We didn't find another pointer still touching the
                // view, release it.
                releaseViewForPointerUp(ev);
            }
        }
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp(ev);
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    }
}

From source file:com.vincestyling.traversaless.ViewPager.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    if (mFakeDragging) {
        // A fake drag is in progress already, ignore this real one
        // but still eat the touch events.
        // (It is likely that the user is multi-touching the screen.)
        return true;
    }/*w  ww. j ava  2s . c  o  m*/

    if (ev.getAction() == MotionEvent.ACTION_DOWN && ev.getEdgeFlags() != 0) {
        // Don't handle edge touches immediately -- they may actually belong to one of our
        // descendants.
        return false;
    }

    if (mAdapter == null || mAdapter.getCount() == 0) {
        // Nothing to present or scroll; nothing to touch.
        return false;
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    final int action = ev.getAction();
    boolean needsInvalidate = false;

    switch (action & MotionEventCompat.ACTION_MASK) {
    case MotionEvent.ACTION_DOWN: {
        /*
         * If being flinged and user touches, stop the fling. isFinished
         * will be false if being flinged.
         */
        completeScroll();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        if (!mIsBeingDragged) {
            final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, pointerIndex);
            final float xDiff = Math.abs(x - mLastMotionX);
            final float y = MotionEventCompat.getY(ev, pointerIndex);
            final float yDiff = Math.abs(y - mLastMotionY);
            if (DEBUG)
                Log.v(TAG, "Moved x to " + x + "," + y + " diff=" + xDiff + "," + yDiff);
            if (xDiff > mTouchSlop && xDiff > yDiff) {
                if (DEBUG)
                    Log.v(TAG, "Starting drag!");
                mIsBeingDragged = true;
                mLastMotionX = x;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);
            }
        }
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            final float deltaX = mLastMotionX - x;
            mLastMotionX = x;
            float oldScrollX = getScrollX();
            float scrollX = oldScrollX + deltaX;
            final int width = getWidth();
            final int widthWithMargin = width + mPageMargin;

            final int lastItemIndex = mAdapter.getCount() - 1;
            final float leftBound = Math.max(0, (mCurItem - 1) * widthWithMargin);
            final float rightBound = Math.min(mCurItem + 1, lastItemIndex) * widthWithMargin;
            if (scrollX < leftBound) {
                if (leftBound == 0) {
                    float over = -scrollX;
                    needsInvalidate = mLeftEdge.onPull(over / width);
                }
                scrollX = leftBound;
            } else if (scrollX > rightBound) {
                if (rightBound == lastItemIndex * widthWithMargin) {
                    float over = scrollX - rightBound;
                    needsInvalidate = mRightEdge.onPull(over / width);
                }
                scrollX = rightBound;
            }
            // Don't lose the rounded component
            mLastMotionX += scrollX - (int) scrollX;
            scrollTo((int) scrollX, getScrollY());
            if (mOnPageChangeListener != null) {
                final int position = (int) scrollX / widthWithMargin;
                final int positionOffsetPixels = (int) scrollX % widthWithMargin;
                final float positionOffset = (float) positionOffsetPixels / widthWithMargin;
                mOnPageChangeListener.onPageScrolled(position, positionOffset, positionOffsetPixels);
            }
        }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int widthWithMargin = getWidth() + mPageMargin;
            final int scrollX = getScrollX();
            final int currentPage = scrollX / widthWithMargin;
            int nextPage = initialVelocity > 0 ? currentPage : currentPage + 1;
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            setCurrentItemInternal(mCurItem, true, true);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        mLastMotionX = MotionEventCompat.getX(ev, index);
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionX = MotionEventCompat.getX(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        invalidate();
    }
    return true;
}

From source file:com.sun.swipebacklayout.lib.ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will
 * dispatch callback events as needed before returning. The parent view's
 * onTouchEvent implementation should call this.
 * /*from ww w.j a va  2 s . com*/
 * @param ev The touch event received by the parent view
 */
public void processTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't get
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        final View toCapture = findTopChildUnder((int) x, (int) y);
        saveInitialMotion(x, y, pointerId);

        // Since the parent is already directly processing this touch
        // event,
        // there is no reason to delay for a slop before dragging.
        // Start immediately if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgesTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);

        // A ViewDragHelper can only manipulate one view at a time.
        if (mDragState == STATE_IDLE) {
            // If we're idle we can do anything! Treat it like a normal
            // down event.

            final View toCapture = findTopChildUnder((int) x, (int) y);
            tryCaptureViewForDrag(toCapture, pointerId);

            final int edgesTouched = mInitialEdgesTouched[pointerId];
            if ((edgesTouched & mTrackingEdges) != 0) {
                mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
            }
        } else if (isCapturedViewUnder((int) x, (int) y)) {
            // We're still tracking a captured view. If the same view is
            // under this
            // point, we'll swap to controlling it with this pointer
            // instead.
            // (This will still work if we're "catching" a settling
            // view.)

            tryCaptureViewForDrag(mCapturedView, pointerId);
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_DRAGGING) {
            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, index);
            final float y = MotionEventCompat.getY(ev, index);
            final int idx = (int) (x - mLastMotionX[mActivePointerId]);
            final int idy = (int) (y - mLastMotionY[mActivePointerId]);

            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);

            saveLastMotion(ev);
        } else {
            // Check to see if any pointer is now over a draggable view.
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int pointerId = MotionEventCompat.getPointerId(ev, i);
                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                final float dx = x - mInitialMotionX[pointerId];
                final float dy = y - mInitialMotionY[pointerId];

                reportNewEdgeDrags(dx, dy, pointerId);
                if (mDragState == STATE_DRAGGING) {
                    // Callback might have started an edge drag.
                    break;
                }

                final View toCapture = findTopChildUnder((int) x, (int) y);
                if (checkTouchSlop(toCapture, dx, dy) && tryCaptureViewForDrag(toCapture, pointerId)) {
                    break;
                }
            }
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
            // Try to find another pointer that's still holding on to
            // the captured view.
            int newActivePointer = INVALID_POINTER;
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int id = MotionEventCompat.getPointerId(ev, i);
                if (id == mActivePointerId) {
                    // This one's going away, skip.
                    continue;
                }

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                if (findTopChildUnder((int) x, (int) y) == mCapturedView
                        && tryCaptureViewForDrag(mCapturedView, id)) {
                    newActivePointer = mActivePointerId;
                    break;
                }
            }

            if (newActivePointer == INVALID_POINTER) {
                // We didn't find another pointer still touching the
                // view, release it.
                releaseViewForPointerUp();
            }
        }
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp();
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    }
}

From source file:com.fastbuildlibrary.widget.swipebacklayout.ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will
 * dispatch callback events as needed before returning. The parent view's
 * onTouchEvent implementation should call this.
 *
 * @param ev The touch event received by the parent view
 *///  www .  j  av a2  s. c  o m
public void processTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't execute
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        final View toCapture = findTopChildUnder((int) x, (int) y);

        saveInitialMotion(x, y, pointerId);

        // Since the parent is already directly processing this touch
        // event,
        // there is no reason to delay for a slop before dragging.
        // Start immediately if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgeTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);

        // A ViewDragHelper can only manipulate one view at a time.
        if (mDragState == STATE_IDLE) {
            // If we're idle we can do anything! Treat it like a normal
            // down event.

            final View toCapture = findTopChildUnder((int) x, (int) y);
            tryCaptureViewForDrag(toCapture, pointerId);

            final int edgesTouched = mInitialEdgeTouched[pointerId];
            if ((edgesTouched & mTrackingEdges) != 0) {
                mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
            }
        } else if (isCapturedViewUnder((int) x, (int) y)) {
            // We're still tracking a captured view. If the same view is
            // under this
            // point, we'll swap to controlling it with this pointer
            // instead.
            // (This will still work if we're "catching" a settling
            // view.)

            tryCaptureViewForDrag(mCapturedView, pointerId);
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_DRAGGING) {
            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, index);
            final float y = MotionEventCompat.getY(ev, index);
            final int idx = (int) (x - mLastMotionX[mActivePointerId]);
            final int idy = (int) (y - mLastMotionY[mActivePointerId]);

            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);

            saveLastMotion(ev);
        } else {
            // Check to see if any pointer is now over a draggable view.
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int pointerId = MotionEventCompat.getPointerId(ev, i);
                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                final float dx = x - mInitialMotionX[pointerId];
                final float dy = y - mInitialMotionY[pointerId];

                reportNewEdgeDrags(dx, dy, pointerId);
                if (mDragState == STATE_DRAGGING) {
                    // Callback might have started an edge drag.
                    break;
                }

                final View toCapture = findTopChildUnder((int) x, (int) y);
                if (checkTouchSlop(toCapture, dx, dy) && tryCaptureViewForDrag(toCapture, pointerId)) {
                    break;
                }
            }
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
            // Try to find another pointer that's still holding on to
            // the captured view.
            int newActivePointer = INVALID_POINTER;
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int id = MotionEventCompat.getPointerId(ev, i);
                if (id == mActivePointerId) {
                    // This one's going away, skip.
                    continue;
                }

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                if (findTopChildUnder((int) x, (int) y) == mCapturedView
                        && tryCaptureViewForDrag(mCapturedView, id)) {
                    newActivePointer = mActivePointerId;
                    break;
                }
            }

            if (newActivePointer == INVALID_POINTER) {
                // We didn't find another pointer still touching the
                // view, release it.
                releaseViewForPointerUp();
            }
        }
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp();
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    }
}

From source file:com.xander.drag.ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will dispatch callback events
 * as needed before returning. The parent view's onTouchEvent implementation should call this.
 *
 * @param ev The touch event received by the parent view
 *//*from  w  ww. jav a  2 s.  c  o  m*/
public void processTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't get
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        final View toCapture = findTopChildUnder((int) x, (int) y);

        saveInitialMotion(x, y, pointerId);

        // Since the parent is already directly processing this touch event,
        // there is no reason to delay for a slop before dragging.
        // Start immediately if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgesTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);

        // A ViewDragHelper can only manipulate one view at a time.
        if (mDragState == STATE_IDLE) {
            // If we're idle we can do anything! Treat it like a normal down event.

            final View toCapture = findTopChildUnder((int) x, (int) y);
            tryCaptureViewForDrag(toCapture, pointerId);

            final int edgesTouched = mInitialEdgesTouched[pointerId];
            if ((edgesTouched & mTrackingEdges) != 0) {
                mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
            }
        } else if (isCapturedViewUnder((int) x, (int) y)) {
            // We're still tracking a captured view. If the same view is under this
            // point, we'll swap to controlling it with this pointer instead.
            // (This will still work if we're "catching" a settling view.)

            tryCaptureViewForDrag(mCapturedView, pointerId);
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_DRAGGING) {
            // If pointer is invalid then skip the ACTION_MOVE.
            if (!isValidPointerForActionMove(mActivePointerId))
                break;

            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, index);
            final float y = MotionEventCompat.getY(ev, index);
            final int idx = (int) (x - mLastMotionX[mActivePointerId]);
            final int idy = (int) (y - mLastMotionY[mActivePointerId]);

            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);

            saveLastMotion(ev);
        } else {
            // Check to see if any pointer is now over a draggable view.
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int pointerId = MotionEventCompat.getPointerId(ev, i);

                // If pointer is invalid then skip the ACTION_MOVE.
                if (!isValidPointerForActionMove(pointerId))
                    continue;

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                final float dx = x - mInitialMotionX[pointerId];
                final float dy = y - mInitialMotionY[pointerId];

                reportNewEdgeDrags(dx, dy, pointerId);
                if (mDragState == STATE_DRAGGING) {
                    // Callback might have started an edge drag.
                    break;
                }

                final View toCapture = findTopChildUnder((int) x, (int) y);
                if (checkTouchSlop(toCapture, dx, dy) && tryCaptureViewForDrag(toCapture, pointerId)) {
                    break;
                }
            }
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
            // Try to find another pointer that's still holding on to the captured view.
            int newActivePointer = INVALID_POINTER;
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int id = MotionEventCompat.getPointerId(ev, i);
                if (id == mActivePointerId) {
                    // This one's going away, skip.
                    continue;
                }

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                if (findTopChildUnder((int) x, (int) y) == mCapturedView
                        && tryCaptureViewForDrag(mCapturedView, id)) {
                    newActivePointer = mActivePointerId;
                    break;
                }
            }

            if (newActivePointer == INVALID_POINTER) {
                // We didn't find another pointer still touching the view, release it.
                releaseViewForPointerUp();
            }
        }
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp();
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    }
}

From source file:co.codecrunch.musicplayerlite.slidinguppanelhelper.ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will
 * dispatch callback events as needed before returning. The parent view's
 * onTouchEvent implementation should call this.
 *
 * @param ev/*from  w  w  w.j av a  2 s  .  co  m*/
 *            The touch event received by the parent view
 */
public void processTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't get
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        final View toCapture = findTopChildUnder((int) x, (int) y);

        saveInitialMotion(x, y, pointerId);

        // Since the parent is already directly processing this touch event,
        // there is no reason to delay for a slop before dragging.
        // Start immediately if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgesTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);

        // A ViewDragHelper can only manipulate one view at a time.
        if (mDragState == STATE_IDLE) {
            // If we're idle we can do anything! Treat it like a normal down
            // event.

            final View toCapture = findTopChildUnder((int) x, (int) y);
            tryCaptureViewForDrag(toCapture, pointerId);

            final int edgesTouched = mInitialEdgesTouched[pointerId];
            if ((edgesTouched & mTrackingEdges) != 0) {
                mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
            }
        } else if (isCapturedViewUnder((int) x, (int) y)) {
            // We're still tracking a captured view. If the same view is
            // under this
            // point, we'll swap to controlling it with this pointer
            // instead.
            // (This will still work if we're "catching" a settling view.)

            tryCaptureViewForDrag(mCapturedView, pointerId);
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_DRAGGING) {
            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, index);
            final float y = MotionEventCompat.getY(ev, index);
            final int idx = (int) (x - mLastMotionX[mActivePointerId]);
            final int idy = (int) (y - mLastMotionY[mActivePointerId]);

            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);

            saveLastMotion(ev);
        } else {
            // Check to see if any pointer is now over a draggable view.
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int pointerId = MotionEventCompat.getPointerId(ev, i);
                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                final float dx = x - mInitialMotionX[pointerId];
                final float dy = y - mInitialMotionY[pointerId];

                reportNewEdgeDrags(dx, dy, pointerId);
                if (mDragState == STATE_DRAGGING) {
                    // Callback might have started an edge drag.
                    break;
                }

                final View toCapture = findTopChildUnder((int) x, (int) y);
                if (checkTouchSlop(toCapture, dx, dy) && tryCaptureViewForDrag(toCapture, pointerId)) {
                    break;
                }
            }
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
            // Try to find another pointer that's still holding on to the
            // captured view.
            int newActivePointer = INVALID_POINTER;
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int id = MotionEventCompat.getPointerId(ev, i);
                if (id == mActivePointerId) {
                    // This one's going away, skip.
                    continue;
                }

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                if (findTopChildUnder((int) x, (int) y) == mCapturedView
                        && tryCaptureViewForDrag(mCapturedView, id)) {
                    newActivePointer = mActivePointerId;
                    break;
                }
            }

            if (newActivePointer == INVALID_POINTER) {
                // We didn't find another pointer still touching the view,
                // release it.
                releaseViewForPointerUp();
            }
        }
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp();
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    }
}

From source file:com.example.zw.demolist.widget.ViewDragHelper.java

/**
 * Process a touch event received by the parent view. This method will dispatch callback events
 * as needed before returning. The parent view's onTouchEvent implementation should call this.
 *
 * @param ev The touch event received by the parent view
 *//*  w  ww. j  av a2 s .  c o  m*/
public void processTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);
    final int actionIndex = MotionEventCompat.getActionIndex(ev);

    if (action == MotionEvent.ACTION_DOWN) {
        // Reset things for a new event stream, just in case we didn't get
        // the whole previous stream.
        cancel();
    }

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(ev);

    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        final float x = ev.getX();
        final float y = ev.getY();
        final int pointerId = MotionEventCompat.getPointerId(ev, 0);
        final View toCapture = findTopChildUnder((int) x, (int) y);

        saveInitialMotion(x, y, pointerId);

        // Since the parent is already directly processing this touch event,
        // there is no reason to delay for a slop before dragging.
        // Start immediately if possible.
        tryCaptureViewForDrag(toCapture, pointerId);

        final int edgesTouched = mInitialEdgesTouched[pointerId];
        if ((edgesTouched & mTrackingEdges) != 0) {
            mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        final float x = MotionEventCompat.getX(ev, actionIndex);
        final float y = MotionEventCompat.getY(ev, actionIndex);

        saveInitialMotion(x, y, pointerId);

        // A ViewDragHelper can only manipulate one view at a time.
        if (mDragState == STATE_IDLE) {
            // If we're idle we can do anything! Treat it like a normal down event.

            final View toCapture = findTopChildUnder((int) x, (int) y);
            tryCaptureViewForDrag(toCapture, pointerId);

            final int edgesTouched = mInitialEdgesTouched[pointerId];
            if ((edgesTouched & mTrackingEdges) != 0) {
                mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
            }
        } else if (isCapturedViewUnder((int) x, (int) y)) {
            // We're still tracking a captured view. If the same view is under this
            // point, we'll swap to controlling it with this pointer instead.
            // (This will still work if we're "catching" a settling view.)

            tryCaptureViewForDrag(mCapturedView, pointerId);
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        if (mDragState == STATE_DRAGGING) {
            final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, index);
            final float y = MotionEventCompat.getY(ev, index);
            final int idx = (int) (x - mLastMotionX[mActivePointerId]);
            final int idy = (int) (y - mLastMotionY[mActivePointerId]);

            dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);

            saveLastMotion(ev);
        } else {
            // Check to see if any pointer is now over a draggable view.
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int pointerId = MotionEventCompat.getPointerId(ev, i);
                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                final float dx = x - mInitialMotionX[pointerId];
                final float dy = y - mInitialMotionY[pointerId];

                reportNewEdgeDrags(dx, dy, pointerId);
                if (mDragState == STATE_DRAGGING) {
                    // Callback might have started an edge drag.
                    break;
                }

                final View toCapture = findTopChildUnder((int) x, (int) y);
                if (checkTouchSlop(toCapture, dx, dy) && tryCaptureViewForDrag(toCapture, pointerId)) {
                    break;
                }
            }
            saveLastMotion(ev);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP: {
        final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
        if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
            // Try to find another pointer that's still holding on to the captured view.
            int newActivePointer = INVALID_POINTER;
            final int pointerCount = MotionEventCompat.getPointerCount(ev);
            for (int i = 0; i < pointerCount; i++) {
                final int id = MotionEventCompat.getPointerId(ev, i);
                if (id == mActivePointerId) {
                    // This one's going away, skip.
                    continue;
                }

                final float x = MotionEventCompat.getX(ev, i);
                final float y = MotionEventCompat.getY(ev, i);
                if (findTopChildUnder((int) x, (int) y) == mCapturedView
                        && tryCaptureViewForDrag(mCapturedView, id)) {
                    newActivePointer = mActivePointerId;
                    break;
                }
            }

            if (newActivePointer == INVALID_POINTER) {
                // We didn't find another pointer still touching the view, release it.
                releaseViewForPointerUp();
            }
        }
        clearMotionHistory(pointerId);
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mDragState == STATE_DRAGGING) {
            releaseViewForPointerUp();
        }
        cancel();
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mDragState == STATE_DRAGGING) {
            dispatchViewReleased(0, 0);
        }
        cancel();
        break;
    }
    default:
        break;

    }
}