Example usage for android.view VelocityTracker computeCurrentVelocity

List of usage examples for android.view VelocityTracker computeCurrentVelocity

Introduction

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

Prototype

public void computeCurrentVelocity(int units, float maxVelocity) 

Source Link

Document

Compute the current velocity based on the points that have been collected.

Usage

From source file:com.bahrini.pager.pager.RtlSupportViewPager.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    //       if (!isSwipeBlocked(ev)) return false; 

    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;
    }/*from  www.ja  v  a2  s  .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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        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;
                requestParentDisallowInterceptTouchEvent(true);
                mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                        : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);

                // Disallow Parent Intercept, just in case
                ViewParent parent = getParent();
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            needsInvalidate |= performDrag(x, mBlockedDirection);
        }
        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 width = getClientWidth();
            final int scrollX = getScrollX();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollX / width) - ii.offset) / ii.widthFactor;
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            final int totalDelta = (int) (x - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);

            if (mCutOffPage == -1
                    || (nextPage <= mCutOffPage && mPagerDirection == PagerDirection.PAGER_DIRECTION_LTR)
                    || (nextPage >= mCutOffPage && mPagerDirection == PagerDirection.PAGER_DIRECTION_RTL))
                setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            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) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:com.av.remusic.widget.RoundViewPager.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;
    }//from w ww.j ava 2  s. com

    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;
    Log.e("round", "onevent");

    switch (action & MotionEventCompat.ACTION_MASK) {

    case MotionEvent.ACTION_DOWN: {
        Log.e("round", "ondown");
        isSingleTouch = true;

        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        Log.e("round", "onmove");
        if (!mIsBeingDragged) {
            final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            if (pointerIndex == -1) {
                // A child has consumed some touch events and put us into an inconsistent state.
                needsInvalidate = resetTouch();
                break;
            }
            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!");

                isSingleTouch = false;
                if (mAnimationChange != null) {
                    mAnimationChange.onPause();
                }

                mIsBeingDragged = true;
                requestParentDisallowInterceptTouchEvent(true);
                mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                        : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);

                // Disallow Parent Intercept, just in case
                ViewParent parent = getParent();
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            needsInvalidate |= performDrag(x);
        }
        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 width = getClientWidth();
            final int scrollX = getScrollX();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final float marginOffset = (float) mPageMargin / width;
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollX / width) - ii.offset) / (ii.widthFactor + marginOffset);
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            final int totalDelta = (int) (x - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            needsInvalidate = resetTouch();
        }
        Log.e("round", "onup" + isSingleTouch);
        //                if(mAnimationChange != null && isSingleTouch){
        //                    mAnimationChange.onReStart();
        //        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            needsInvalidate = resetTouch();
        }
        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) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:com.telerik.examples.primitives.ExampleViewPagerBase.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;
    }/*from   w  ww . j  ava 2s .co  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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = getMotionEventCoordinate(ev);
        mLastMotionY = mInitialMotionY = getInvertedMotionEventCoordinate(ev);
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        if (!mIsBeingDragged) {
            final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = getMotionEventCompatCoordinate(ev, pointerIndex);
            final float xDiff = Math.abs(x - mLastMotionX);
            final float y = getInvertedMotionEventCompatCoordinate(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;
                requestParentDisallowInterceptTouchEvent(true);
                mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                        : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);

                // Disallow Parent Intercept, just in case
                ViewParent parent = getParent();
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = getMotionEventCompatCoordinate(ev, activePointerIndex);
            needsInvalidate |= performDrag(x);
        }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = this.getSwipeVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int length = getClientLength();
            final int scroll = getScroll(this);
            final ItemInfo ii = infoForCurrentScrollPosition();
            final int currentPage = ii.position;
            final float pageOffset = (((float) scroll / length) - ii.offset) / ii.lengthFactor;
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = getMotionEventCompatCoordinate(ev, activePointerIndex);
            final int totalDelta = (int) (x - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        final float x = getMotionEventCompatCoordinate(ev, index);
        mLastMotionX = x;
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionX = getMotionEventCompatCoordinate(ev,
                MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:com.example.mvpdemo.widget.NarrowViewPager.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    Log.i("xx", "=========== onTouchEvent ============");
    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  av  a2 s.co 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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
        final float y = MotionEventCompat.getY(ev, pointerIndex);
        if (!mIsBeingDragged && !isBeingPushed) {
            final float x = MotionEventCompat.getX(ev, pointerIndex);
            final float xDiff = Math.abs(x - mLastMotionX);
            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 && mDragDistance == 0) {
                if (DEBUG)
                    Log.v(TAG, "Starting drag!");
                mIsBeingDragged = true;
                requestParentDisallowInterceptTouchEvent(true);
                mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                        : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);

                // Disallow Parent Intercept, just in case
                ViewParent parent = getParent();
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }
            } else if (yDiff > mTouchSlop && xDiff < yDiff) {
                isBeingPushed = true;
                requestParentDisallowInterceptTouchEvent(true);
                mLastMotionY = y - mLastMotionY > 0 ? mLastMotionY + mTouchSlop : mLastMotionY - mTouchSlop;
                mLastMotionX = x;
                mOnDragY = y;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);

                // Disallow Parent Intercept, just in case
                ViewParent parent = getParent();
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }
            }

        }
        // Not else! Note that mIsBeingDragged can be set above.
        if (mIsBeingDragged) {

            // Scroll to follow the motion event
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            needsInvalidate |= performDrag(x);

        }

        if (isBeingPushed) {
            if (mOnDragY > 0) {
                mDragDistance += y - mOnDragY;
                mOnDragY = y;
                childScrollUp(mDragDistance);
                //                            mOnDragY = y;
            }
        }

        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {

            mOnDragY = 0;

            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int width = getClientWidth();
            final int scrollX = getScrollX();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollX / width) - ii.offset) / ii.widthFactor;
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float x = MotionEventCompat.getX(ev, activePointerIndex);
            final int totalDelta = (int) (x - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            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) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:com.tjych.swip.vertical.DirectionalViewPager.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;
    }//from   ww w.j  a v  a  2  s.com

    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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();
        mIsBeingDragged = true;
        setScrollState(SCROLL_STATE_DRAGGING);

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        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 (mOrientation == HORIZONTAL) {
                if (xDiff > mTouchSlop && xDiff > yDiff) {
                    if (DEBUG)
                        Log.v(TAG, "Starting drag!");
                    mIsBeingDragged = true;
                    mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                            : mInitialMotionX - mTouchSlop;
                    mLastMotionY = y;
                    setScrollState(SCROLL_STATE_DRAGGING);
                    setScrollingCacheEnabled(true);
                }
            } else {
                if (yDiff > mTouchSlop && yDiff > xDiff) {
                    if (DEBUG)
                        Log.v(TAG, "Starting drag!");
                    mIsBeingDragged = true;
                    mLastMotionX = x;
                    mLastMotionY = y - mInitialMotionY > 0 ? mInitialMotionY + mTouchSlop
                            : mInitialMotionY - mTouchSlop;
                    ;
                    setScrollState(SCROLL_STATE_DRAGGING);
                    setScrollingCacheEnabled(true);
                }
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);

            final float coord = mOrientation == HORIZONTAL ? MotionEventCompat.getX(ev, activePointerIndex)
                    : MotionEventCompat.getY(ev, activePointerIndex);

            needsInvalidate |= performDrag(coord);
        }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = mOrientation == HORIZONTAL
                    ? (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId)
                    : (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int dimension = getClientDimension();
            final int scrollCoord = getScrollCoord();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollCoord / dimension) - ii.offset) / ii.dimensionFactor;
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float coord = mOrientation == HORIZONTAL ? MotionEventCompat.getX(ev, activePointerIndex)
                    : MotionEventCompat.getY(ev, activePointerIndex);
            final int totalDelta = mOrientation == HORIZONTAL ? (int) (coord - mInitialMotionX)
                    : (int) (coord - mInitialMotionY);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mStartEdge.onRelease() | mEndEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mStartEdge.onRelease() | mEndEdge.onRelease();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);

        if (mOrientation == HORIZONTAL) {
            final float coord = MotionEventCompat.getX(ev, index);
            mLastMotionX = coord;
        } else {
            final float coord = MotionEventCompat.getY(ev, index);
            mLastMotionY = coord;
        }

        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);

        if (mOrientation == HORIZONTAL) {
            mLastMotionX = MotionEventCompat.getX(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        } else {
            mLastMotionY = MotionEventCompat.getY(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        }

        break;
    }
    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:cn.androidy.materialdesignsample.ryanharterviewpager.ViewPager.java

/**
 * End a fake drag of the pager./*from www  .j  a va2 s  . c  om*/
 *
 * @see #beginFakeDrag()
 * @see #fakeDragBy(float)
 */
public void endFakeDrag() {
    if (!mFakeDragging) {
        throw new IllegalStateException("No fake drag in progress. Call beginFakeDrag first.");
    }

    final VelocityTracker velocityTracker = mVelocityTracker;
    velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);

    final ItemInfo ii = infoForCurrentScrollPosition();
    final int currentPage = ii.position;

    int initialVelocity, totalDelta;
    float pageOffset;
    if (isOrientationHorizontal()) {
        initialVelocity = (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId);
        mPopulatePending = true;
        final int width = getClientWidth();
        final int scrollX = getScrollX();
        pageOffset = (((float) scrollX / width) - ii.offset) / ii.sizeFactor;
        totalDelta = (int) (mLastMotionX - mInitialMotionX);
    } else {
        initialVelocity = (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId);
        mPopulatePending = true;
        final int height = getClientHeight();
        final int scrollY = getScrollY();
        pageOffset = (((float) scrollY / height) - ii.offset) / ii.sizeFactor;
        totalDelta = (int) (mLastMotionY - mInitialMotionY);
    }

    int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
    setCurrentItemInternal(nextPage, true, true, initialVelocity);
    endDrag();

    mFakeDragging = false;
}

From source file:com.jit.lib.widget.verticalviewpager.VerticalViewPager.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;
    }//from  w  w w  .j a va2 s.com

    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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();
        mIsBeingDragged = true;
        setScrollState(SCROLL_STATE_DRAGGING);

        // Remember where the motion event started
        mLastMotionY = mInitialMotionY = ev.getY();
        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 (yDiff > mTouchSlop && yDiff > xDiff) {
                if (DEBUG)
                    Log.v(TAG, "Starting drag!");
                mIsBeingDragged = true;
                mLastMotionY = y - mInitialMotionY > 0 ? mInitialMotionY + mTouchSlop
                        : mInitialMotionY - mTouchSlop;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        //                if (mIsBeingDragged) {
        //                    // Scroll to follow the motion event
        //                    final int activePointerIndex = MotionEventCompat.findPointerIndex(
        //                            ev, mActivePointerId);
        //                    final float y = MotionEventCompat.getY(ev, activePointerIndex);
        //                    needsInvalidate |= performDrag(y);
        //                }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            //                    velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            //                    int initialVelocity = (int) VelocityTrackerCompat.getYVelocity(
            //                            velocityTracker, mActivePointerId);
            int minimumVelocity = (int) DensityUtil.getHeightInPx(getContext());
            velocityTracker.computeCurrentVelocity(minimumVelocity, minimumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int height = getHeight();
            final int scrollY = getScrollY();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollY / height) - ii.offset) / ii.heightFactor;
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float y = MotionEventCompat.getY(ev, activePointerIndex);
            final int totalDelta = (int) (y - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mTopEdge.onRelease() | mBottomEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mTopEdge.onRelease() | mBottomEdge.onRelease();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        final float y = MotionEventCompat.getY(ev, index);
        mLastMotionY = y;
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionY = MotionEventCompat.getY(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:com.example.sky.test.view.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;
    }//from   w ww. j a  va 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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        mActivePointerId = ev.getPointerId(0);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        if (!mIsBeingDragged) {
            final int pointerIndex = ev.findPointerIndex(mActivePointerId);
            if (pointerIndex == -1) {
                // A child has consumed some touch events and put us into an inconsistent
                // state.
                needsInvalidate = resetTouch();
                break;
            }
            final float x = ev.getX(pointerIndex);
            final float xDiff = Math.abs(x - mLastMotionX);
            final float y = ev.getY(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;
                requestParentDisallowInterceptTouchEvent(true);
                mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                        : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);

                // Disallow Parent Intercept, just in case
                ViewParent parent = getParent();
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = ev.findPointerIndex(mActivePointerId);
            final float x = ev.getX(activePointerIndex);
            needsInvalidate |= performDrag(x);
        }
        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 width = getClientWidth();
            final int scrollX = getScrollX();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final float marginOffset = (float) mPageMargin / width;
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollX / width) - ii.offset) / (ii.widthFactor + marginOffset);
            final int activePointerIndex = ev.findPointerIndex(mActivePointerId);
            final float x = ev.getX(activePointerIndex);
            final int totalDelta = (int) (x - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            needsInvalidate = resetTouch();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            needsInvalidate = resetTouch();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        final float x = ev.getX(index);
        mLastMotionX = x;
        mActivePointerId = ev.getPointerId(index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionX = ev.getX(ev.findPointerIndex(mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:com.ex.lib.ext.widget.verticalviewpager.VerticalViewPager.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;
    }//from  ww  w .j  a v  a 2s  .  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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();
        mIsBeingDragged = true;
        setScrollState(SCROLL_STATE_DRAGGING);

        // Remember where the motion event started
        mLastMotionY = mInitialMotionY = ev.getY();
        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 (yDiff > mTouchSlop && yDiff > xDiff) {
                if (DEBUG)
                    Log.v(TAG, "Starting drag!");
                mIsBeingDragged = true;
                mLastMotionY = y - mInitialMotionY > 0 ? mInitialMotionY + mTouchSlop
                        : mInitialMotionY - mTouchSlop;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        //                if (mIsBeingDragged) {
        //                    // Scroll to follow the motion event
        //                    final int activePointerIndex = MotionEventCompat.findPointerIndex(
        //                            ev, mActivePointerId);
        //                    final float y = MotionEventCompat.getY(ev, activePointerIndex);
        //                    needsInvalidate |= performDrag(y);
        //                }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            //                    velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            //                    int initialVelocity = (int) VelocityTrackerCompat.getYVelocity(
            //                            velocityTracker, mActivePointerId);
            int minimumVelocity = (int) getContext().getResources().getDisplayMetrics().heightPixels;
            velocityTracker.computeCurrentVelocity(minimumVelocity, minimumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int height = getHeight();
            final int scrollY = getScrollY();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollY / height) - ii.offset) / ii.heightFactor;
            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            final float y = MotionEventCompat.getY(ev, activePointerIndex);
            final int totalDelta = (int) (y - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mTopEdge.onRelease() | mBottomEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mTopEdge.onRelease() | mBottomEdge.onRelease();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        final float y = MotionEventCompat.getY(ev, index);
        mLastMotionY = y;
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionY = MotionEventCompat.getY(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

From source file:example.luojing.androidsourceanalysis.ViewPager.java

/**
 * //from  w  ww.  j a  v  a  2 s  .com
 */
@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;
    }

    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: {
        mScroller.abortAnimation();
        mPopulatePending = false;
        populate();

        // Remember where the motion event started
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        mActivePointerId = ev.getPointerId(0);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        if (!mIsBeingDragged) {
            final int pointerIndex = ev.findPointerIndex(mActivePointerId);
            if (pointerIndex == -1) {
                // A child has consumed some touch events and put us into an inconsistent
                // state.
                needsInvalidate = resetTouch();
                break;
            }
            final float x = ev.getX(pointerIndex);
            final float xDiff = Math.abs(x - mLastMotionX);
            final float y = ev.getY(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;
                requestParentDisallowInterceptTouchEvent(true);
                mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                        : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                setScrollState(SCROLL_STATE_DRAGGING);
                setScrollingCacheEnabled(true);

                // Disallow Parent Intercept, just in case
                ViewParent parent = getParent();
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }
            }
        }
        // Not else! Note that mIsBeingDragged can be set above.
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            final int activePointerIndex = ev.findPointerIndex(mActivePointerId);
            final float x = ev.getX(activePointerIndex);
            needsInvalidate |= performDrag(x);
        }
        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 width = getClientWidth();
            final int scrollX = getScrollX();
            final ItemInfo ii = infoForCurrentScrollPosition();
            final float marginOffset = (float) mPageMargin / width;
            final int currentPage = ii.position;
            final float pageOffset = (((float) scrollX / width) - ii.offset) / (ii.widthFactor + marginOffset);
            final int activePointerIndex = ev.findPointerIndex(mActivePointerId);
            final float x = ev.getX(activePointerIndex);
            final int totalDelta = (int) (x - mInitialMotionX);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);

            needsInvalidate = resetTouch();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            needsInvalidate = resetTouch();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        final float x = ev.getX(index);
        mLastMotionX = x;
        mActivePointerId = ev.getPointerId(index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionX = ev.getX(ev.findPointerIndex(mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}