Getting problem in sending data from recyclerView

问题:

After doing many hit and try method and observing other stackoverflow code, I was able to send data to next activity. I want to know: Is it safe to call cursor.moveToPosition twice in onBindViewHolder method.

public class recyclerViewSongAdapter extends RecyclerView.Adapter<recyclerViewSongAdapter.MyViewHolder> {
        private final Activity callingActivity;
        private final Cursor songCursor;

        public recyclerViewSongAdapter(Activity activity, Cursor cursor) {
            callingActivity = activity;
            songCursor = cursor;
            if(songCursor != null) {
                songPathIndex = songCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA);
                songTitleIndex = songCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE);
                songAlbumIndex = songCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM);
            }
        }

        public class MyViewHolder extends RecyclerView.ViewHolder { //implements View.OnClickListener{
            public TextView titleTextView, albumTextView;
            public View parentLayout;

            public MyViewHolder(View view) {
                super(view);
                titleTextView = view.findViewById(R.id.songTitleId);
                albumTextView = view.findViewById(R.id.songAlbumId);
                parentLayout = view.findViewById(R.id.parentLinearId);

            }
        }

        @NonNull
        @Override
        public MyViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
            View itemView = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.song_element, viewGroup, false);
            return new MyViewHolder(itemView);
        }

        public String songTitle, songAlbum;
        int songPathIndex, songTitleIndex, songAlbumIndex;

        @Override
        public void onBindViewHolder(@NonNull final MyViewHolder myViewHolder, final int position) {
            if(songCursor != null) {
                songCursor.moveToPosition(position);
                songTitle = songCursor.getString(songTitleIndex);
                songAlbum = songCursor.getString(songAlbumIndex);

                myViewHolder.titleTextView.setText("" + songTitle);
                myViewHolder.albumTextView.setText("" + songAlbum);

                myViewHolder.parentLayout.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        songCursor.moveToPosition(position);
                        string title = songCursor.getString(songTitleIndex); 
                        Intent intent = new Intent(callingActivity.getApplicationContext(), SongPlaying.class);
                        intent.putExtra("mayank", "" + title);
                        callingActivity.startActivity(intent);
                    }
                });
            }
        }

        @Override
        public int getItemCount() {
            return (songCursor == null) ? 0 : songCursor.getCount();
        }
    }

Edit: Earlier my question was how to send the title of clicked item to next Activity and now my question is using cursor.moveToPosition twice, a good idea.

回答1:

This is not a correct way to use cursor in recycler adapter however this is a solution for you to send current title to the next activity.

write below code in your onclick listener

    songCursor.moveToPosition(position);
    String title= songCursor.getString(songTitleIndex);
    Intent intent = new Intent(callingActivity.this,SongPlaying.class);
    intent.putExtra("mayank", "" + title);
    callingActivity.startActivity(intent);