用安卓给我写个音频播放器代码

非常感谢您的提问。以下是一份简单的安卓音频播放器代码：

import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity {

    private MediaPlayer mediaPlayer;
    private Button playBtn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        playBtn = (Button) findViewById(R.id.playBtn);
        mediaPlayer = MediaPlayer.create(this, R.raw.song);

        playBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (mediaPlayer.isPlaying()) {
                    mediaPlayer.pause();
                    playBtn.setText("Play");
                } else {
                    mediaPlayer.start();
                    playBtn.setText("Pause");
                }
            }
        });

        mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
            @Override
            public void onCompletion(MediaPlayer mediaPlayer) {
                playBtn.setText("Play");
            }
        });
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (mediaPlayer != null) {
            mediaPlayer.pause();
            playBtn.setText("Play");
        }
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (mediaPlayer != null && !mediaPlayer.isPlaying()) {
            mediaPlayer.start();
            playBtn.setText("Pause");
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (mediaPlayer != null) {
            mediaPlayer.release();
            mediaPlayer = null;
        }
    }
}

希望这份代码能够帮助你实现音频播放功能。如果您有任何问题或建议，随时欢迎向我提出。