ViewPager判斷是向左划還是右划

   //記錄上一次滑動的positionOffsetPixels值
    private int lastValue = -1;
     private boolean isLeft = true;


 mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
            if (positionOffset != 0) {
                if (lastValue >= positionOffsetPixels) {
                    //右滑
                    isLeft = false;
                } else if (lastValue < positionOffsetPixels) {
                    //左滑
                    isLeft = true;
                }
                setIndiactorView(positionOffset,isLeft);
            }
            lastValue = positionOffsetPixels;

        }

        @Override
        public void onPageSelected(int position) {
            if (isLeft){
                Log.e("onPageScrolled","--->左划");
            }else {
                Log.e("onPageScrolled","--->右划");

            }
        }

        @Override
        public void onPageScrollStateChanged(int state) {

        }
    });