问题：子RecycleView网格布局的话，使用GridSpacingItemDecoration控制间隔大小，不断上下滑动，部分间距会不断变大，超出界面
解决方法：
代码语言：java复制if (holder.rlv_select.getItemDecorationCount() == 0) {
int spacing = mContext.getResources().getDimensionPixelSize(R.dimen.dp_20);
holder.recyclerView.addItemDecoration(new GridSpacingItemDecoration(4, spacing, false));
}或者（未使用过）
代码语言：javascript复制holder.recyclerView.removeItemDecoration();附带询问AI可以得到的代码：
代码语言：javascript复制public class GridSpacingItemDecoration extends RecyclerView.ItemDecoration {
private int spanCount;
private int spacing;
private int topSpacing;
private boolean includeEdge;
public GridSpacingItemDecoration(int spanCount, int spacing, boolean includeEdge) {
this.spanCount = spanCount;
this.spacing = spacing;
this.includeEdge = includeEdge;
}
public GridSpacingItemDecoration(int spanCount, int spacing, int topSpacing, boolean includeEdge) {
this.spanCount = spanCount;
this.spacing = spacing;
this.topSpacing = topSpacing;
this.includeEdge = includeEdge;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view); // item position
int column = position % spanCount; // item column
if (includeEdge) {
outRect.left = spacing - column * spacing / spanCount; // spacing - column * ((1f / spanCount) * spacing)
outRect.right = (column 1) * spacing / spanCount; // (column 1) * ((1f / spanCount) * spacing)
if (position < spanCount) { // top edge
outRect.top = spacing;
}
outRect.bottom = spacing; // item bottom
} else {
outRect.left = column * spacing / spanCount; // column * ((1f / spanCount) * spacing)
outRect.right = spacing - (column 1) * spacing / spanCount; // spacing - (column 1) * ((1f / spanCount) * spacing)
if (position >= spanCount) {
outRect.top = topSpacing; // item top
}
}
}
}
