1 @Override
2 public void onScrolled(int dx, int dy) {
3     super.onScrolled(dx, dy);
4     sx = sx +dx;
5     if (scrollViewListener != null && isMark) {
6         scrollViewListener.onScrollChanged(this, sx, 0);
7     }
8 }

 1 @Override
 2 public void onScrollChanged(Object scrollView, int x, int y) {
 3     int width1 = CommonUtil.getScreenWidth(this) - DensityUtils.dip2px(this, 60);
 4     int width2 = CommonUtil.getScreenWidth(this);
 5     if (scrollView == rvHead) {
 6         rvFoot.setmark(false);
 7         rvFoot.scrollTo(x * width2 / width1, y);
 8     } else if (scrollView == rvFoot) {
 9         rvHead.setmark(false);
10         rvHead.scrollTo(x * width1 / width2, y);
11     }
12     rvHead.setmark(true);
13     rvFoot.setmark(true);
14 }

1 @Override
2 public void scrollTo(int x, int y) {
3     scrollBy(x-sx,0);
4 }

 1 public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
 2         super.onScrollStateChanged(recyclerView, newState);
 3         if (newState == RecyclerView.SCROLL_STATE_IDLE) {
 4             int mmSelected;
 5             //当控件停止滚动时，获取可视范围第一个item的位置，滚动调整控件以使选中的item刚好处于正中间
 6             int firstVisiblePos = mLayoutManager.findFirstVisibleItemPosition();
 7             if (firstVisiblePos == RecyclerView.NO_POSITION) {
 8                 return;
 9             }
10             Rect rect = new Rect();
11             mLayoutManager.findViewByPosition(firstVisiblePos).getHitRect(rect);
12             if (Math.abs(rect.left) > mItemWidth / 2) {
13                 smoothScrollBy(rect.right, 0);
14                 mmSelected = firstVisiblePos + 1;
15             } else {
16                 smoothScrollBy(rect.left, 0);
17                 mmSelected = firstVisiblePos;
18             }
19             if (Math.abs(rect.left) == 0 && mOnSelectListener != null && mmSelected != mSelected) {
20                 mSelected = mmSelected;
21                 mOnSelectListener.onSelect(mSelected);
22             }
23         }
24     }
25 }

 1 @Override
 2 public boolean fling(int velocityX, int velocityY) {
 3     int v;
 4     int touchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop();
 5     if (Math.abs(velocityX) <= 3*touchSlop) {
 6         return false;
 7     }
 8     mPhysicalCoeff = SensorManager.GRAVITY_EARTH   // g (m/s^2)
 9             * 39.37f               // inch/meter
10             * getContext().getResources().getDisplayMetrics().density * 160.0f                 // pixels per inch
11             * 0.84f;
12     int firstVisiblePos = mLayoutManager.findFirstVisibleItemPosition();
13     if (firstVisiblePos == RecyclerView.NO_POSITION) {
14         return false;
15     }
16     Rect rect = new Rect();
17     mLayoutManager.findViewByPosition(firstVisiblePos).getHitRect(rect);
18     double n = getSplineFlingDistance(velocityX) / mItemWidth;
19     int num = Double.valueOf(n).intValue();
20     if (velocityX > 0)
21         v = Double.valueOf(getVelocityByDistance(num * mItemWidth + Math.abs(rect.right)- DensityUtils.dip2px(getContext(), 20))).intValue();
22     else
23         v = Double.valueOf(getVelocityByDistance(num * mItemWidth + Math.abs(rect.left)+ DensityUtils.dip2px(getContext(), 20))).intValue();
24     if (velocityX < 0) {
25         v = -v;
26     }
27     return super.fling(v, velocityY);
28 }