question: public boolean canScroll ( int direction ) { RectF bitmapRect = getBitmapRect ( ) ; updateRect ( bitmapRect , mScrollRect ) ; Rect imageViewRect = new Rect ( ) ; getGlobalVisibleRect ( imageViewRect ) ; if ( null == bitmapRect ) { return false ; } if ( bitmapRect . right >= imageViewRect . right ) { if ( direction < 0 ) { return Math . abs ( bitmapRect . right - imageViewRect . right ) > SCROLL_DELTA_THRESHOLD ; } } double bitmapScrollRectDelta = Math . abs ( bitmapRect . left - mScrollRect . left ) ; return bitmapScrollRectDelta > SCROLL_DELTA_THRESHOLD ; }
target:  Determines whether this ImageViewTouch can be scrolled.