StaggeredGridLayoutManager重新排序项目,而不考虑定义的边距

时间:2020-01-15 07:56:33

标签: android android-layout android-recyclerview staggeredgridlayoutmanager

我,StaggeredGridLayoutManager使用RecyclerView,以便在宽度相等但高度不同的2列中显示项目。由于我希望项目之间的空隙相等,因此使用了以下ItemDecoration

public class ImageCardDecoration extends RecyclerView.ItemDecoration {
    private int margin;

    public ImageCardDecoration(Context context) {
        margin = 5;
    }

    @Override
    public void getItemOffsets(@NonNull Rect outRect, @NonNull View view, @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {
        super.getItemOffsets(outRect, view, parent, state);

        int position = parent.getChildAdapterPosition(view);
        int spanIndex =((StaggeredGridLayoutManager.LayoutParams)view.getLayoutParams()).getSpanIndex();
        if (spanIndex == 0) {
            outRect.left = 2 * margin;
            outRect.right = margin;
        } else {
            outRect.left = margin;
            outRect.right = 2 * margin;
        }
        outRect.top = 2 * margin;

        if (position == 0 || position == 1)
            outRect.top = 14 * margin;
    }
}

,效果很好。但是在滚动recyclerview并获得Idle后,布局管理器会重新排序一些项目以填补空白(这很好,我想要这种行为),但是如果某项目从第二列移动到第一列,它将不使用上面代码中为第一列定义的边距,并且如果项目从第一列移到第二列,则不会再更新其边距。如何解决这种不当行为? before reordering after reordering

1 个答案:

答案 0 :(得分:0)

以下解决方案很有魅力!

        recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrollStateChanged(@NonNull final RecyclerView recyclerView, int newState) {
            super.onScrollStateChanged(recyclerView, newState);

            if (newState == RecyclerView.SCROLL_STATE_IDLE)
                recyclerView.invalidateItemDecorations();
        }
}