Example usage for android.support.v4.view MotionEventCompat ACTION_MASK

List of usage examples for android.support.v4.view MotionEventCompat ACTION_MASK

Introduction

In this page you can find the example usage for android.support.v4.view MotionEventCompat ACTION_MASK.

Prototype

int ACTION_MASK

To view the source code for android.support.v4.view MotionEventCompat ACTION_MASK.

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Document

Synonym for MotionEvent#ACTION_MASK .

Usage

From source file:com.mobilesolutionworks.android.imagepaging.ImageViewPager.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  v  a 2  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;
                mLastMotionX = mInitialMotionX;
                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 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.lzy.mmd.widget.viewpager.ViewPagerCompat.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    try {/*from   w ww  .  j  a va 2 s . c  o  m*/
        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 = 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);
            }
            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);
                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;
    } catch (IllegalArgumentException e) {
        // 
        e.printStackTrace();
        return false;
    }
}

From source file:com.financeyun.commonlibrary.ui.view.DLGViewPager.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  . java2s .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 (ev.getX() > getWidth() / 5 || getCurrentItem() == 0)
            return super.onTouchEvent(ev);
        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 (xDiff > mTouchSlop && xDiff > yDiff) {
                mIsBeingDragged = true;
                mLastMotionX = x - mInitialMotionX > 0 ? mInitialMotionX + mTouchSlop
                        : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                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 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 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.goodfriends.personalchef.viewflipper.MyViewPager.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 w  w. j ava 2 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: {
        MyLogger.showLogWithLineNum(3, "?MyViewPager ---> onTouchEvent 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 (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);
            }
        }
        // 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 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.pan.panautolooperviewpager.lib.LoopViewPager.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  av a 2  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: {
        //   MyLogger.showLogWithLineNum(3, "?yViewPager---> onTouchEvent 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 (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);
            }
        }
        // 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 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.guide.ViewPager.java

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    /*//from   w  w  w . ja  va 2  s .co  m
     * This method JUST determines whether we want to intercept the motion.
     * If we return true, onMotionEvent will be called and we do the actual
     * scrolling there.
     */

    final int action = ev.getAction() & MotionEventCompat.ACTION_MASK;

    // Always take care of the touch gesture being complete.
    if (action == MotionEvent.ACTION_CANCEL || action == MotionEvent.ACTION_UP) {
        // Release the drag.
        if (DEBUG)
            Log.v(TAG, "Intercept done!");
        mIsBeingDragged = false;
        mIsUnableToDrag = false;
        mActivePointerId = INVALID_POINTER;
        if (mVelocityTracker != null) {
            mVelocityTracker.recycle();
            mVelocityTracker = null;
        }
        return false;
    }

    // Nothing more to do here if we have decided whether or not we
    // are dragging.
    if (action != MotionEvent.ACTION_DOWN) {
        if (mIsBeingDragged) {
            if (DEBUG)
                Log.v(TAG, "Intercept returning true!");
            return true;
        }
        if (mIsUnableToDrag) {
            if (DEBUG)
                Log.v(TAG, "Intercept returning false!");
            return false;
        }
    }

    switch (action) {
    case MotionEvent.ACTION_MOVE: {
        /*
         * mIsBeingDragged == false, otherwise the shortcut would have
         * caught it. Check whether the user has moved far enough from his
         * original down touch.
         */

        /*
         * Locally do absolute value. mLastMotionY is set to the y value of
         * the down event.
         */
        final int activePointerId = mActivePointerId;
        if (activePointerId == INVALID_POINTER) {
            // If we don't have a valid id, the touch down wasn't on
            // content.
            break;
        }

        final int pointerIndex = MotionEventCompat.findPointerIndex(ev, activePointerId);
        final float x = MotionEventCompat.getX(ev, pointerIndex);
        final float dx = x - mLastMotionX;
        final float xDiff = Math.abs(dx);
        final float y = MotionEventCompat.getY(ev, pointerIndex);
        final float dy = y - mLastMotionY;
        final float yDiff = Math.abs(y - mInitialMotionY);
        if (DEBUG)
            Log.v(TAG, "Moved x to " + x + "," + y + " diff=" + xDiff + "," + yDiff);

        if (isOrientationHorizontal()) {
            if (dx != 0 && !isGutterDrag(mLastMotionX, dx)
                    && canScroll(this, false, (int) dx, (int) x, (int) y)) {
                // Nested view has scrollable area under this point. Let it
                // be handled there.
                mLastMotionX = x;
                mLastMotionY = y;
                mIsUnableToDrag = true;
                return false;
            }
            if (xDiff > mTouchSlop && xDiff * 0.5f > yDiff) {
                if (DEBUG)
                    Log.v(TAG, "Starting drag!");
                mIsBeingDragged = true;
                setScrollState(SCROLL_STATE_DRAGGING);
                mLastMotionX = dx > 0 ? mInitialMotionX + mTouchSlop : mInitialMotionX - mTouchSlop;
                mLastMotionY = y;
                setScrollingCacheEnabled(true);
            } else if (yDiff > mTouchSlop) {
                // The finger has moved enough in the vertical
                // direction to be counted as a drag... abort
                // any attempt to drag horizontally, to work correctly
                // with children that have scrolling containers.
                if (DEBUG)
                    Log.v(TAG, "Starting unable to drag!");
                mIsUnableToDrag = true;
            }
            if (mIsBeingDragged) {
                // Scroll to follow the motion event
                if (performDrag(x)) {
                    ViewCompat.postInvalidateOnAnimation(this);
                }
            }
        } else {
            if (dy != 0 && !isGutterDrag(mLastMotionY, dy)
                    && canScroll(this, false, (int) dx, (int) x, (int) y)) {
                // Nested view has scrollable area under this point. Let it
                // be handled there.
                mLastMotionX = x;
                mLastMotionY = y;
                mIsUnableToDrag = true;
                return false;
            }
            if (yDiff > mTouchSlop && yDiff * 0.5f > xDiff) {
                if (DEBUG)
                    Log.v(TAG, "Starting drag!");
                mIsBeingDragged = true;
                setScrollState(SCROLL_STATE_DRAGGING);
                mLastMotionY = dy > 0 ? mInitialMotionY + mTouchSlop : mInitialMotionY - mTouchSlop;
                mLastMotionX = x;
                setScrollingCacheEnabled(true);
            } else if (xDiff > mTouchSlop) {
                // The finger has moved enough in the vertical
                // direction to be counted as a drag... abort
                // any attempt to drag horizontally, to work correctly
                // with children that have scrolling containers.
                if (DEBUG)
                    Log.v(TAG, "Starting unable to drag!");
                mIsUnableToDrag = true;
            }
            if (mIsBeingDragged) {
                // Scroll to follow the motion event
                if (performDrag(y)) {
                    ViewCompat.postInvalidateOnAnimation(this);
                }
            }
        }
        break;
    }

    case MotionEvent.ACTION_DOWN: {
        /*
         * Remember location of down touch. ACTION_DOWN always refers to
         * pointer index 0.
         */
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        mIsUnableToDrag = false;

        mScroller.computeScrollOffset();
        int distance = 0;
        if (isOrientationHorizontal()) {
            distance = Math.abs(mScroller.getFinalX() - mScroller.getCurrX());
        } else {
            distance = Math.abs(mScroller.getFinalY() - mScroller.getCurrY());
        }
        if (mScrollState == SCROLL_STATE_SETTLING && distance > mCloseEnough) {
            // Let the user 'catch' the pager as it animates.
            mScroller.abortAnimation();
            mPopulatePending = false;
            populate();
            mIsBeingDragged = true;
            setScrollState(SCROLL_STATE_DRAGGING);
        } else {
            completeScroll(false);
            mIsBeingDragged = false;
        }

        if (DEBUG)
            Log.v(TAG, "Down at " + mLastMotionX + "," + mLastMotionY + " mIsBeingDragged=" + mIsBeingDragged
                    + "mIsUnableToDrag=" + mIsUnableToDrag);
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        break;
    }

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

    /*
     * The only time we want to intercept motion events is if we are in the
     * drag mode.
     */
    return mIsBeingDragged;
}

From source file:cn.bmob.otaku.number_z.view.imagepager.PinchImageViewPager.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  w w . j  a v a  2 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:
        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);
        }
        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);
            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.aizou.core.widget.pagerIndicator.viewpager.FixedViewPager.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    if (!isCanScroll) {
        return false;
    }//from   ww w .j  a va2s .c o  m
    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 = 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);
        }
        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);
            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.minoon.stackviewpagersample.StackViewPager.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   www . j a  v a  2  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:
        // 

        //                Log.d(TAG, "[Action] Move, " + mCurItem);
        if (!mIsBeingDragged) {
            // ??????

            // x????y???
            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);
            // x????????????? && x????y??????
            // -> ?
            if (xDiff > mTouchSlop && xDiff > yDiff) {
                //                        if (DEBUG) Log.v(TAG, "Starting drag!");
                // ???View???????????
                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:
        //                Log.d(TAG, "[Action] Up, " + mIsBeingDragged);
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId);
            mPopulatePending = true;
            final int width = getClientWidth();
            // [Changed]
            //                    final int scrollX = getScrollX();
            final int scrollX = getOverlapScrollX();
            final ItemInfo ii = infoForCurrentScrollPosition();
            //                    Log.d(TAG, "[Action] Up, ItemInfo. position: " + ii.position + ", offset: " + ii.offset + ", scrolling: " + ii.scrolling);
            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);
            //                    Log.d(TAG, "[Action] Up, currentPage = " + currentPage + ", pageOffset: " + pageOffset +
            //                            ", initialVelocity" + initialVelocity + ", totalDelta" + totalDelta);
            int nextPage = determineTargetPage(currentPage, pageOffset, initialVelocity, totalDelta);
            setCurrentItemInternal(nextPage, true, true, initialVelocity);
            //                    Log.d(TAG, "[Action] Up, nextPage = " + nextPage);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        //                Log.d(TAG, "[Action] Cancel");
        if (mIsBeingDragged) {
            scrollToItem(mCurItem, true, 0, false);
            mActivePointerId = INVALID_POINTER;
            endDrag();
            needsInvalidate = mLeftEdge.onRelease() | mRightEdge.onRelease();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        //                Log.d(TAG, "[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:
        //                Log.d(TAG, "[Action] pointer up");
        onSecondaryPointerUp(ev);
        mLastMotionX = MotionEventCompat.getX(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }
    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
    return true;
}

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

/**
 * ?/*  w  w w.j  a v  a 2s  . co  m*/
 */
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    /*
     * This method JUST determines whether we want to intercept the motion.
     * If we return true, onMotionEvent will be called and we do the actual
     * scrolling there.
     */

    final int action = ev.getAction() & MotionEventCompat.ACTION_MASK;

    // Always take care of the touch gesture being complete.
    if (action == MotionEvent.ACTION_CANCEL || action == MotionEvent.ACTION_UP) {
        // Release the drag.
        if (DEBUG)
            Log.v(TAG, "Intercept done!");
        resetTouch();
        return false;
    }

    // Nothing more to do here if we have decided whether or not we
    // are dragging.
    if (action != MotionEvent.ACTION_DOWN) {
        if (mIsBeingDragged) {
            if (DEBUG)
                Log.v(TAG, "Intercept returning true!");
            return true;
        }
        if (mIsUnableToDrag) {
            if (DEBUG)
                Log.v(TAG, "Intercept returning false!");
            return false;
        }
    }

    switch (action) {
    case MotionEvent.ACTION_MOVE: {
        /*
         * mIsBeingDragged == false, otherwise the shortcut would have caught it. Check
         * whether the user has moved far enough from his original down touch.
         */

        /*
        * Locally do absolute value. mLastMotionY is set to the y value
        * of the down event.
        */
        final int activePointerId = mActivePointerId;
        if (activePointerId == INVALID_POINTER) {
            // If we don't have a valid id, the touch down wasn't on content.
            break;
        }

        final int pointerIndex = ev.findPointerIndex(activePointerId);
        final float x = ev.getX(pointerIndex);
        final float dx = x - mLastMotionX;
        final float xDiff = Math.abs(dx);
        final float y = ev.getY(pointerIndex);
        final float yDiff = Math.abs(y - mInitialMotionY);
        if (DEBUG)
            Log.v(TAG, "Moved x to " + x + "," + y + " diff=" + xDiff + "," + yDiff);

        if (dx != 0 && !isGutterDrag(mLastMotionX, dx) && canScroll(this, false, (int) dx, (int) x, (int) y)) {
            // Nested view has scrollable area under this point. Let it be handled there.
            mLastMotionX = x;
            mLastMotionY = y;
            mIsUnableToDrag = true;
            return false;
        }
        if (xDiff > mTouchSlop && xDiff * 0.5f > yDiff) {
            if (DEBUG)
                Log.v(TAG, "Starting drag!");
            mIsBeingDragged = true;
            requestParentDisallowInterceptTouchEvent(true);
            setScrollState(SCROLL_STATE_DRAGGING);
            mLastMotionX = dx > 0 ? mInitialMotionX + mTouchSlop : mInitialMotionX - mTouchSlop;
            mLastMotionY = y;
            setScrollingCacheEnabled(true);
        } else if (yDiff > mTouchSlop) {
            // The finger has moved enough in the vertical
            // direction to be counted as a drag...  abort
            // any attempt to drag horizontally, to work correctly
            // with children that have scrolling containers.
            if (DEBUG)
                Log.v(TAG, "Starting unable to drag!");
            mIsUnableToDrag = true;
        }
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            if (performDrag(x)) {
                ViewCompat.postInvalidateOnAnimation(this);
            }
        }
        break;
    }

    case MotionEvent.ACTION_DOWN: {
        /*
         * Remember location of down touch.
         * ACTION_DOWN always refers to pointer index 0.
         */
        mLastMotionX = mInitialMotionX = ev.getX();
        mLastMotionY = mInitialMotionY = ev.getY();
        mActivePointerId = ev.getPointerId(0);
        mIsUnableToDrag = false;

        mIsScrollStarted = true;
        mScroller.computeScrollOffset();
        if (mScrollState == SCROLL_STATE_SETTLING
                && Math.abs(mScroller.getFinalX() - mScroller.getCurrX()) > mCloseEnough) {
            // Let the user 'catch' the pager as it animates.
            mScroller.abortAnimation();
            mPopulatePending = false;
            populate();
            mIsBeingDragged = true;
            requestParentDisallowInterceptTouchEvent(true);
            setScrollState(SCROLL_STATE_DRAGGING);
        } else {
            completeScroll(false);
            mIsBeingDragged = false;
        }

        if (DEBUG) {
            Log.v(TAG, "Down at " + mLastMotionX + "," + mLastMotionY + " mIsBeingDragged=" + mIsBeingDragged
                    + "mIsUnableToDrag=" + mIsUnableToDrag);
        }
        break;
    }

    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        break;
    }

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

    /*
     * The only time we want to intercept motion events is if we are in the
     * drag mode.
     */
    return mIsBeingDragged;
}