主程序
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private MediaPlayer mediaPlayer = new MediaPlayer();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btnPlay = (Button) findViewById(R.id.btnPlay);
Button btnPause = (Button) findViewById(R.id.btnPause);
Button btnStop = (Button) findViewById(R.id.btnStop);
btnPlay.setOnClickListener(this);
btnPause.setOnClickListener(this);
btnStop.setOnClickListener(this);
//权限判断,如果没有权限就请求权限
if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
} else {
initMediaPlayer();//初始化播放器 MediaPlayer
}
}
private void initMediaPlayer() {
try {
File file = new File(Environment.getExternalStorageDirectory(), "music.mp3");
mediaPlayer.setDataSource(file.getPath()+"/"+R.raw.a);//指定音频文件路径
mediaPlayer.setLooping(true);//设置为循环播放
mediaPlayer.prepare();//初始化播放器MediaPlayer
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
switch (requestCode){
case 1:
if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
initMediaPlayer();
}else{
Toast.makeText(this, "拒绝权限,将无法使用程序。", Toast.LENGTH_LONG).show();
finish();
}
break;
default:
}
}
@Override
public void onClick(View v) {
switch (v.getId()){
case R.id.btnPlay:
//如果没在播放中,立刻开始播放。
if(!mediaPlayer.isPlaying()){
mediaPlayer.start();
}
break;
case R.id.btnPause:
//如果在播放中,立刻暂停。
if(mediaPlayer.isPlaying()){
mediaPlayer.pause();
}
break;
case R.id.btnStop:
//如果在播放中,立刻停止。
if(mediaPlayer.isPlaying()){
mediaPlayer.reset();
initMediaPlayer();//初始化播放器 MediaPlayer
}
break;
default:
break;
}
}
@Override
protected void onDestroy() {
super.onDestroy();
if(mediaPlayer != null){
mediaPlayer.stop();
mediaPlayer.release();
}
}
}
main布局文件
<?xml version="1.0" encoding="utf-8"?><Button
android:id="@+id/btnPlay"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAllCaps="false"
android:text="Play"/>
<Button
android:id="@+id/btnPause"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAllCaps="false"
android:text="Pause"/>
<Button
android:id="@+id/btnStop"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAllCaps="false"
android:text="Stop"/>