在RecyclerView中播放和释放音频

Question

I'm learning android and currently RecyclerView, so in this example I'm playing a specific raw sound file when clicking a play button and then releasing it when it's done. I could seriously use some pointers on what is the best practice however as I have a few issues and questions:

• I have a problem with transiting states so if I press play very quickly I'll get an IllegalStateException , probably from trying to release an already released player.
• I should apparently also nullify after release and do a null check prior but since I'm using it in a nested scope it has to be declared final and can't be nulled which is confusing, I've obviously missed something.
• setting the clickListner on an item in onBindViewHolder also seems significantly slower and less responsive than adding a clickListner on the entire row in the viewHolder class.

What is the best practice for setting up your mediaPlayer and managing your resources correctly with RecyclerView and what am I doing wrong that would cause crashes and "slowness"?

//ViewHolder

public static class myHolder extends RecyclerView.ViewHolder implements View.OnClickListener{


    ImageView playBtn;

    public myHolder(View v){
        super(v);
        playBtn = (ImageView) v.findViewById(R.id.playBtn);
        v.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
    }

}

//onBindViewHolder / onCompletionListener

  @Override
public void onBindViewHolder(myHolder holder, int position) {
    myClass item = itemList.get(position);
    final MediaPlayer mediaPlayer = MediaPlayer.create(holder.itemView.getContext(), item.getAudioSource());

   holder.playBtn.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v) {

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

Answer 1

If you're only listening in user interaction you can drop setOnCompleteListener() and instead define your play/stop code in (in order) OnLongClickListener() and OnClickListener . Like this:

holder.playBtn.setOnClickListener(new View.OnClickListener(){
    @Override
    public void onClick(View v) {
       //Code to stop playing and release resources
    }
});

holder.playBtn.setOnLongClickListener(new View.OnClickListener(){
        @Override
        public void onLongClick(View v) {
           //Code to start playing 

           return false; //!!This is important so that OnClick() would be called after releasing the button
        }
    });

Answer 2

OBS As I'm answering my own question I can NOT say that this is acctualy good practice but it did solve the issues I was having, if anyone spots an error or has a better more efficient way then please post an answer and elaborate.

• instead of declaring the MediaPlayer inside the onBindViewHolder I made it a class variable, this allowed me to avoid having it final and be able to nullify it after release.
• I then defined it inside the onClick method instead to make sure that it would never be null and always be declared when needed.
• I had to make my holder and "item" final in order to use them inside the onClick but this seems to have worked (recyclerView magic I guess)

The app no longer crashes and onCompletionListener should clear all resources, this is the current code:

//class variable mediaplayer and onCompletionListener method

MediaPlayer mediaPlayer;

//onCompletionListener method
MediaPlayer.OnCompletionListener mCompletionListener = new MediaPlayer.OnCompletionListener() {
    @Override
    public void onCompletion(MediaPlayer mp) {
        mp.release();
        mediaPlayer = null;
    }
};

//onBindViewHolder

@Override
public void onBindViewHolder(final itemHolder holder, int position) {
    final Items item = mItemList.get(position);

    holder.playBtn.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v) {
            mediaPlayer = MediaPlayer.create(holder.itemView.getContext(), item.getAudioSource());
            if(mediaPlayer != null) {
                mediaPlayer.start();
                mediaPlayer.setOnCompletionListener(mCompletionListener);
            }
        }
    });
}