android - 在 recyclerview 中为项目设置悬停

Question

我有一个 ListView ，因为我有卡片 View 的回收 View ...当我选择其中任何一个时，应该会有一个 float 布局，其中有 3 个按钮。我正在使用这个库 enter link description here .

我在适配器中使用这个库并在 Activity 中设置了该适配器，但我一进入 Activity 应用程序就崩溃并出现 NullPointerException。出现的错误是，当我膨胀两个 xml 文件但我想首先膨胀 abc_card_view_video 然后单击其中任何一个时，新文件 hover_card_view 应该膨胀但旧文件应该在后台。

帮我摆脱困境。谢谢

     public class LessonVideoAdapter extends RecyclerView.Adapter<LessonDataHolder> {

            private List<VideoList> slipList;
            private Context mContext;
            public BlurLayout samplelayout;


            public LessonVideoAdapter() {
                slipList = new ArrayList<>();
                slipList.add(new VideoList("Chapter 1", R.drawable.demo_one));
                slipList.add(new VideoList("Chapter 2", R.drawable.demo_two));
                slipList.add(new VideoList("Chapter 3", R.drawable.demo_one));

            }

            @Override
            public LessonDataHolder onCreateViewHolder(ViewGroup parent, int viewType) {
                Context context = parent.getContext();
                LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                View view = inflater.inflate(R.layout.abc_card_view_video, parent, false);
return new LessonDataHolder(view);          
  }

            @Override
            public void onBindViewHolder(LessonDataHolder holder, int position) {
                VideoList s = slipList.get(position);
                holder.bindSlip(s);

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

        class LessonDataHolder extends RecyclerView.ViewHolder {

            private TextView nameOfSlip;
            private ImageView slipImage;
            private Context context;
            public LessonDataHolder(View itemView) {
                super(itemView);

                context = itemView.getContext();
                nameOfSlip = (TextView) itemView.findViewById(R.id.demoText);
                slipImage = (ImageView) itemView.findViewById(R.id.imageViewDemoVideo);

            }

            public void bindSlip(VideoList videoList) {
                nameOfSlip.setText(videoList.stringSlipName);
                slipImage.setImageResource(videoList.stringImage);
            }
        }

        class VideoList {
            public String stringSlipName;
            public int stringImage;

            public VideoList(String stringSlipName, int stringImage) {
                this.stringImage = stringImage;
                this.stringSlipName = stringSlipName;
            }

        }

Answer 1

您应该在项目的监听器或点击中编写此代码

 View view = inflater.inflate(R.layout.abc_card_view_video, parent, false);
    samplelayout = (BlurLayout) parent.findViewById(R.id.blur_layout);
                View hover = inflater.inflate(R.layout.hover_card_view, null);
                samplelayout.setHoverView(hover);