Question

我的应用程序中发生了非常不寻常的事情。当我单击此视图时，将前一个位置设置为当前位置，以便下次按下该视图时，方法notifyItemChanged（position）将刷新前一个位置。奇怪的是，它第一次像吊饰一样工作，但是当涉及到第二次或第三次等等时，它不会刷新该项目。在logcat中，一切似乎也很正常。它遍历代码，没有警告或错误。这是我的代码：

我的变量previous_pos在适配器类的顶部初始化。

private int previous_pos = -1;

这是我的Adapter类的代码段

@Override
public void onBindViewHolder(@NonNull final TrackHolder holder, final int position) {
    holder.mInstrumentalName.setText(tracks.get(position).getInstrumentalName());
    holder.mProducer.setText(tracks.get(position).getProducer());


    Log.d("position", Integer.toString(holder.getAdapterPosition()));
    holder.mPlayButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            if (previous_pos != -1) {
                notifyItemChanged(previous_pos);
            }

            previous_pos = holder.getAdapterPosition();
            holder.mPlayButton.toggle();



            if (mediaPlayer.isPlaying()) {

                mediaPlayer.reset();
                mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
                try {
                    mediaPlayer.setDataSource(tracks.get(position).getMusicLink());
                } catch (IOException e) {
                    e.printStackTrace();
                }
                mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                    @Override
                    public void onPrepared(MediaPlayer mediaPlayer) {
                        mediaPlayer.start();
                    }
                });
                mediaPlayer.prepareAsync();

            } else {
                mediaPlayer.reset();
                mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
                try {
                    mediaPlayer.setDataSource(tracks.get(position).getMusicLink());
                    previous_link = tracks.get(position).getMusicLink();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                    @Override
                    public void onPrepared(MediaPlayer mediaPlayer) {
                        mediaPlayer.start();
                    }
                });
                mediaPlayer.prepareAsync();
            }


        }
    });

    mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
        @Override
        public void onCompletion(MediaPlayer mediaPlayer) {
            mediaPlayer.release();
        }
    });

    holder.setItemClickListener(new ItemClickListener() {
        @Override
        public void onItemClick(View v, int pos) {
            Toast.makeText(context, Integer.toString(tracks.size()), Toast.LENGTH_SHORT).show();
        }
    });
}

holder.mPlayButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {


            if (previous_pos != -1) {
                notifyItemChanged(previous_pos);
            }

            previous_pos = holder.getAdapterPosition();
            holder.mPlayButton.toggle();



            if (mediaPlayer.isPlaying()) {

                mediaPlayer.reset();
                mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
                try {
                    mediaPlayer.setDataSource(tracks.get(position).getMusicLink());
                } catch (IOException e) {
                    e.printStackTrace();
                }
                mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                    @Override
                    public void onPrepared(MediaPlayer mediaPlayer) {
                        mediaPlayer.start();
                    }
                });
                mediaPlayer.prepareAsync();

            } else {
                mediaPlayer.reset();
                mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
                try {
                    mediaPlayer.setDataSource(tracks.get(position).getMusicLink());
                    previous_link = tracks.get(position).getMusicLink();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                    @Override
                    public void onPrepared(MediaPlayer mediaPlayer) {
                        mediaPlayer.start();
                    }
                });
                mediaPlayer.prepareAsync();
            }


        }
    });

Answer 1

只需将setOnClickListener从onBindViewHolder移到onCreateViewHolder。

notifyitemchanged（position）第一次刷新列表中的项目，但此后不再刷新

1 个答案: