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目录

一，效果图

二、技术难点

2.1实现方式

2.2核心代码

三、完整代码

一，效果图

二、技术难点

2.1实现方式

1. 横向RecyclerView，因为recyclerview可以实现数据的更多加载，所以当position为最后一个的时候，可以重新请求第二页的数据，进行刷新；
2. 后期也可以在此基础上添加Viewpager实现动态联动；

2.2核心代码

1. 解决滑动时候，Item的动态的位置校准，对齐下方的指示图标；

       public static CenterViewItem getMinDifferItem(List<CenterViewItem> itemHeights){
           CenterViewItem minItem = itemHeights.get(0); //默认第一个是最小差值
           for (int i = 0; i < itemHeights.size(); i++) {
               //遍历获取最小差值
               if (itemHeights.get(i).differ <= minItem.differ){
                   minItem = itemHeights.get(i);
               }
           }
           return minItem;
       }

2. 解决滑动时候，流畅的大小变化，重写LinearLayoutManager；

     @Override
       public int scrollVerticallyBy(int dy, RecyclerView.Recycler recycler, RecyclerView.State state) {
           int orientation = getOrientation();
           if (orientation == VERTICAL) {
               int scrolled = super.scrollVerticallyBy(dy, recycler, state);
               float midpoint = getHeight() / 2.f;
               float d0 = 0.f;
               float d1 = mShrinkDistance * midpoint;
               float s0 = 1.f;
               float s1 = 1.f - mShrinkAmount;
               for (int i = 0; i < getChildCount(); i++) {
                   View child = getChildAt(i);
                   float childMidpoint =
                           (getDecoratedBottom(child) + getDecoratedTop(child)) / 2.f;
                   float d = Math.min(d1, Math.abs(midpoint - childMidpoint));
                   float scale = s0 + (s1 - s0) * (d - d0) / (d1 - d0);
                   child.setScaleX(scale);
                   child.setScaleY(scale);
               }
               return scrolled;
           } else {
               return 0;
           }
       }
   
       @Override
       public int scrollHorizontallyBy(int dx, RecyclerView.Recycler recycler, RecyclerView.State state) {
           int orientation = getOrientation();
           if (orientation == HORIZONTAL) {
               int scrolled = super.scrollHorizontallyBy(dx, recycler, state);
   
               float midpoint = getWidth() / 2.f;
               float d0 = 0.f;
               float d1 = mShrinkDistance * midpoint;
               float s0 = 1.f;
               float s1 = 1.f - mShrinkAmount;
               for (int i = 0; i < getChildCount(); i++) {
                   View child = getChildAt(i);
                   float childMidpoint =
                           (getDecoratedRight(child) + getDecoratedLeft(child)) / 2.f;
                   float d = Math.min(d1, Math.abs(midpoint - childMidpoint));
                   float scale = s0 + (s1 - s0) * (d - d0) / (d1 - d0);
                   child.setScaleX(scale);
                   child.setScaleY(scale);
               }
               return scrolled;
           } else {
               return 0;
           }
   
       }

三、完整代码

Recyclerview实现滑动放大ItemView-Android文档类资源-CSDN下载