Andorid多媒体播放中的音乐播放一般是使用MediaPlayer实现的，他对音频文件提供了非常全面的方法。
梳理一下MediaPlayer工作流程,创建出一个Media对象之后用setDataSource()来设置音频文件的路径，再调用Prepare()方法使它进入到工作状态，接下来调用start()即可.
demo如下:
1：在清淡文件中添加sd卡权限
2：布局文件
就写三个按钮，开始播放，暂停播放和重新播放即可
xmlns:app="/apk/res-auto"
xmlns:tools="/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
android:id="@+id/play"
android:text="play"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
android:id="@+id/pause"
android:text="pause"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
android:id="@+id/replay"
android:text="replay"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
3：Activity
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;
import android.Manifest;
import android.content.pm.PackageManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import java.io.File;
import java.io.IOException;
public class MainActivity extends AppCompatActivity {
private Button play;
private Button pause;
private Button replay;
private MediaPlayer mediaPlayer = new MediaPlayer();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
play = findViewById(R.id.play);
pause = findViewById(R.id.pause);
replay = findViewById(R.id.replay);
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 {
try { //权限申请
initMediaPlayer();
} catch (IOException e) {
e.printStackTrace();
}
}
play.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (!mediaPlayer.isPlaying()){
mediaPlayer.start();
}
}
});
pause.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (mediaPlayer.isPlaying()){
mediaPlayer.pause();
}
}
});
replay.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (mediaPlayer.isPlaying()){
mediaPlayer.reset();
try {
initMediaPlayer();
} catch (IOException 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){
try {
initMediaPlayer();
} catch (IOException e) {
e.printStackTrace();
}
}else {
Toast.makeText(MainActivity.this,"权限被拒绝",Toast.LENGTH_LONG).show();
}
break;
default:
}
}
@Override
protected void onDestroy() {
super.onDestroy();
if (mediaPlayer != null){
mediaPlayer.stop();
mediaPlayer.release();
}
}
private void initMediaPlayer() throws IOException {
File file = new File(Environment.getExternalStorageDirectory(),"成磊 - 你不知道的事.mp3"); //这个文件要放在sd卡的根目录下
mediaPlayer.setDataSource(file.getPath());
mediaPlayer.prepare();
}
}
音频文件要放在sd卡的根目录下或自定义文件路径
