@Override
public void onViewDragStateChanged(int state) {
switch (state) {
case ViewDragHelper.STATE_SETTLING:
case ViewDragHelper.STATE_DRAGGING:
{
mScrollingHeaderByHelper = false;
break;
}
case ViewDragHelper.STATE_IDLE:
{
if (mTime > 0 && !Float.isNaN(mVelocity)) {
final float velocity = mVelocity;
if (velocity < 0 && mDrawer.getHeaderTop() <= mDrawer.getHeaderTopMinimum()) {
mDrawer.flingCallback(-velocity);
}
}
mTime = -1;
mDx = Float.NaN;
mDy = Float.NaN;
mVelocity = Float.NaN;
mScrollingHeaderByHelper = false;
break;
}
}
super.onViewDragStateChanged(state);
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
final int top = mDrawer.getHeaderTop(), min = mDrawer.getHeaderTopMinimum();
final boolean showingFullContent = top <= min, flingUp = velocityY < 0;
final boolean verticalFling = Math.abs(velocityY) > Math.abs(velocityX);
if (!verticalFling) return true;
if (showingFullContent) {
if (flingUp) {
// Fling list up when showing full content
if (mDrawer.isScrollingContentCallback()) {
mDrawer.flingCallback(-velocityY);
}
} else {
// Fling down when list reached top and not dragging user ViewDragHelper,
// so we fling header down here
if (!mDrawer.canScrollCallback(1) && !mDrawer.isUsingDragHelper()) {
mDrawer.flingHeader(velocityY);
}
}
} else {
// Header still visible
}
return true;
}