android - 奇怪的 Android RecyclerView (GridLayoutManager) 焦点行为

Question

我有一个带有 GridLayoutManager 的 RecyclerView，每行 2 列。因为开发是针对 Android TV 的，所以我需要专注于导航。

如果我使用向下键导航到任何可见的项目，那没关系。例如，项目 1 -> 项目 3 -> 项目 5 -> 项目 7(仅部分可见。)。但是当我再次按下键时，焦点将移动到项目 10 而不是 9。

我的 GridView 适配器是:

public class GridAdapter extends RecyclerView.Adapter<GridAdapter.ViewHolder> {    
    private ArrayList<String> mDataset;

    public GridAdapter(ArrayList<String> myDataset) {
        mDataset = myDataset;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.grid_item, viewGroup, false);
        ViewHolder vh = new ViewHolder(v);
        return vh;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        holder.txtTitle.setText(mDataset.get(position));    
    }

    @Override
    public int getItemCount() {
        return mDataset.size();
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {

        public TextView txtTitle;
        public ViewHolder(View v) {
            super(v);
            txtTitle = (TextView) v.findViewById(R.id.title);
        }
    }
}

知道如何解决这个问题吗？谢谢。

Answer 1

查看this related post和 Vganin's answer解决您的问题。

I reported this bug to AOSP issue tracker: issue 190526

As I can see from source the issue is because GridLayoutManager uses LinearLayoutManager's implementation of onFocusSearchFailed() which is called when focus approaches the inner border of RecyclerView. LinearLayoutManager's implementation just offers first/last (depends on scrolling direction) element. Hence focus jumps to first/last element of new row.

My workaround for this issue.