SwipeView类似桌面的滑动界面(12)

        } 
         
        private boolean actionDown(MotionEvent event) 
        { 
            mMotionStartX = (int) event.getX(); 
            mMotionStartY = (int) event.getY(); 
            mFirstMotionEvent = false; 
            return false; 
        } 
         
        private boolean actionMove(MotionEvent event) 
        { 
            int newDistance = mMotionStartX - (int) event.getX(); 
            int newDirection; 
             
            if(newDistance<0) //backwards 
            { 
                newDirection =  (mDistanceX+4 <= newDistance) ? 1 : -1;  //the distance +4 is to allow for jitter 
            } 
            else //forwards 
            { 
                newDirection =  (mDistanceX-4 <= newDistance) ? 1 : -1;  //the distance -4 is to allow for jitter 
            } 
             
             
            if(newDirection != mPreviousDirection && !mFirstMotionEvent)//changed direction, so reset start point 
            { 
                mMotionStartX = (int) event.getX(); 
                mDistanceX = mMotionStartX - (int) event.getX(); 
            }