@Override
public boolean onTouchEvent(MotionEvent ev) {
if (!mEnabled) return false;
if (!mIsBeingDragged && !thisTouchAllowed(ev)) return false;
// if (!mIsBeingDragged && !mQuickReturn)
// return false;
final int action = ev.getAction();
if (mVelocityTracker == null) {
mVelocityTracker = VelocityTracker.obtain();
}
mVelocityTracker.addMovement(ev);
switch (action & MotionEventCompat.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
/*
* If being flinged and user touches, stop the fling. isFinished
* will be false if being flinged.
*/
completeScroll();
// Remember where the motion event started
int index = MotionEventCompat.getActionIndex(ev);
mActivePointerId = MotionEventCompat.getPointerId(ev, index);
mLastMotionX = mInitialMotionX = ev.getX();
break;
case MotionEvent.ACTION_MOVE:
if (!mIsBeingDragged) {
determineDrag(ev);
if (mIsUnableToDrag) return false;
}
if (mIsBeingDragged) {
// Scroll to follow the motion event
final int activePointerIndex = getPointerIndex(ev, mActivePointerId);
if (mActivePointerId == INVALID_POINTER) break;
final float x = MotionEventCompat.getX(ev, activePointerIndex);
final float deltaX = mLastMotionX - x;
mLastMotionX = x;
float oldScrollX = getScrollX();
float scrollX = oldScrollX + deltaX;
final float leftBound = getLeftBound();
final float rightBound = getRightBound();
if (scrollX < leftBound) {
scrollX = leftBound;
} else if (scrollX > rightBound) {
scrollX = rightBound;
}
// Don't lose the rounded component
mLastMotionX += scrollX - (int) scrollX;
scrollTo((int) scrollX, getScrollY());
pageScrolled((int) scrollX);
}
break;
case MotionEvent.ACTION_UP:
if (mIsBeingDragged) {
final VelocityTracker velocityTracker = mVelocityTracker;
velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
int initialVelocity =
(int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId);
final int scrollX = getScrollX();
final float pageOffset = (float) (scrollX - getDestScrollX(mCurItem)) / getBehindWidth();
final int activePointerIndex = getPointerIndex(ev, mActivePointerId);
if (mActivePointerId != INVALID_POINTER) {
final float x = MotionEventCompat.getX(ev, activePointerIndex);
final int totalDelta = (int) (x - mInitialMotionX);
int nextPage = determineTargetPage(pageOffset, initialVelocity, totalDelta);
setCurrentItemInternal(nextPage, true, true, initialVelocity);
} else {
setCurrentItemInternal(mCurItem, true, true, initialVelocity);
}
mActivePointerId = INVALID_POINTER;
endDrag();
} else if (mQuickReturn
&& mViewBehind.menuTouchInQuickReturn(mContent, mCurItem, ev.getX() + mScrollX)) {
// close the menu
setCurrentItem(1);
endDrag();
}
break;
case MotionEvent.ACTION_CANCEL:
if (mIsBeingDragged) {
setCurrentItemInternal(mCurItem, true, true);
mActivePointerId = INVALID_POINTER;
endDrag();
}
break;
case MotionEventCompat.ACTION_POINTER_DOWN:
{
final int indexx = MotionEventCompat.getActionIndex(ev);
mLastMotionX = MotionEventCompat.getX(ev, indexx);
mActivePointerId = MotionEventCompat.getPointerId(ev, indexx);
break;
}
case MotionEventCompat.ACTION_POINTER_UP:
onSecondaryPointerUp(ev);
int pointerIndex = getPointerIndex(ev, mActivePointerId);
if (mActivePointerId == INVALID_POINTER) break;
mLastMotionX = MotionEventCompat.getX(ev, pointerIndex);
break;
}
return true;
}
/**
* Set the currently selected page.
*
* @param item Item index to select
* @param smoothScroll True to smoothly scroll to the new item, false to transition immediately
*/
public void setCurrentItem(int item, boolean smoothScroll) {
setCurrentItemInternal(item, smoothScroll, false);
}
void setCurrentItemInternal(int item, boolean smoothScroll, boolean always) {
setCurrentItemInternal(item, smoothScroll, always, 0);
}
/**
* Set the currently selected page. If the CustomViewPager has already been through its first
* layout there will be a smooth animated transition between the current item and the specified
* item.
*
* @param item Item index to select
*/
public void setCurrentItem(int item) {
setCurrentItemInternal(item, true, false);
}