GridRecyclerView.java 文件源码

@Override
protected void attachLayoutAnimationParameters(View child, ViewGroup.LayoutParams params, int index, int count) {

  if (getAdapter() != null && getLayoutManager() instanceof GridLayoutManager){

    GridLayoutAnimationController.AnimationParameters animationParams =
        (GridLayoutAnimationController.AnimationParameters) params.layoutAnimationParameters;

    if (animationParams == null) {
      animationParams = new GridLayoutAnimationController.AnimationParameters();
      params.layoutAnimationParameters = animationParams;
    }

    int columns = ((GridLayoutManager) getLayoutManager()).getSpanCount();

    animationParams.count = count;
    animationParams.index = index;
    animationParams.columnsCount = columns;
    animationParams.rowsCount = count / columns;

    final int invertedIndex = count - 1 - index;
    animationParams.column = columns - 1 - (invertedIndex % columns);
    animationParams.row = animationParams.rowsCount - 1 - invertedIndex / columns;

  } else {
    super.attachLayoutAnimationParameters(child, params, index, count);
  }
}