Android带播放进度条的音乐播放器

以你之姓@ 2022-06-08 04:13 815阅读 0赞

## Android带播放进度条的音乐播放器 ##

**前言:** 使用MediaPlayer实现Android的音乐播放器，能够播放、暂停、停止歌曲；同时使用SeekBar来控制音乐的播放进度，可以通过调节SeekBar的进度来控制播放进度。

**效果图**如下：

![这里写图片描述][SouthEast]

**1. 第一步**

布局文件activity\_main.xml

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_margin="20dp"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    
        <LinearLayout
            android:orientation="vertical"
            android:layout_marginTop="20dp"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
    
            <TextView
                android:id="@+id/music_name"
                android:layout_gravity="center_horizontal"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"/>
    
            <RelativeLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content">
    
                <SeekBar
                    android:id="@+id/seekBar"
                    android:layout_marginTop="80dp"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"/>
    
                <LinearLayout
                    android:layout_below="@id/seekBar"
                    android:layout_alignEnd="@id/seekBar"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content">
    
                    <TextView
                        android:id="@+id/music_cur"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"/>
    
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="/"/>
    
                    <TextView
                        android:id="@+id/music_length"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"/>
    
                </LinearLayout>
    
            </RelativeLayout>
    
        </LinearLayout>
    
       <LinearLayout
           android:gravity="center"
           android:layout_width="match_parent"
           android:layout_height="match_parent">
    
           <ImageButton
               android:id="@+id/play"
               android:src="@mipmap/bofang"
               android:background="@null"
               android:layout_width="wrap_content"
               android:layout_height="wrap_content"/>
    
           <ImageButton
               android:id="@+id/pause"
               android:src="@mipmap/pause"
               android:background="@null"
               android:layout_marginLeft="20dp"
               android:layout_width="wrap_content"
               android:layout_height="wrap_content"/>
    
           <ImageButton
               android:id="@+id/stop"
               android:src="@mipmap/stop"
               android:background="@null"
               android:layout_marginLeft="20dp"
               android:layout_width="wrap_content"
               android:layout_height="wrap_content"/>
    
       </LinearLayout>
    
        <LinearLayout
            android:gravity="bottom|right"
            android:orientation="vertical"
            android:layout_width="match_parent"
            android:layout_height="match_parent">
    
            <ImageButton
                android:id="@+id/volume_plus"
                android:src="@mipmap/volume_increase"
                android:background="@null"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"/>
    
            <ImageButton
                android:id="@+id/volume_decrease"
                android:src="@mipmap/volume_decrease"
                android:background="@null"
                android:layout_marginTop="20dp"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"/>
    
        </LinearLayout>
    
    </RelativeLayout>

**2. 第二步**

Activity——MusicActivity

public class MusicActivity extends AppCompatActivity implements View.OnClickListener {
        
    
        private ImageButton play,pause,stop,volume_plus,volume_decrease;
        private TextView musicName,musicLength,musicCur;
        private SeekBar seekBar;
    
        private MediaPlayer mediaPlayer = new MediaPlayer();
    
        private AudioManager audioManager;
    
        private Timer timer;
    
        int maxVolume,currentVolume;
    
        private boolean isSeekBarChanging;//互斥变量，防止进度条与定时器冲突。
        private int currentPosition;//当前音乐播放的进度
    
        SimpleDateFormat format;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_music);
    
            audioManager = (AudioManager) getSystemService(Service.AUDIO_SERVICE);
    
            format = new SimpleDateFormat("mm:ss");
    
            play = (ImageButton) findViewById(R.id.play);
            pause = (ImageButton) findViewById(R.id.pause);
            stop = (ImageButton) findViewById(R.id.stop);
            volume_plus = (ImageButton) findViewById(R.id.volume_plus);
            volume_decrease = (ImageButton) findViewById(R.id.volume_decrease);
    
            musicName = (TextView) findViewById(R.id.music_name);
            musicLength = (TextView) findViewById(R.id.music_length);
            musicCur = (TextView) findViewById(R.id.music_cur);
    
            seekBar = (SeekBar) findViewById(R.id.seekBar);
            seekBar.setOnSeekBarChangeListener(new MySeekBar());
    
            play.setOnClickListener(MusicActivity.this);
            pause.setOnClickListener(MusicActivity.this);
            stop.setOnClickListener(MusicActivity.this);
            volume_plus.setOnClickListener(MusicActivity.this);
            volume_decrease.setOnClickListener(MusicActivity.this);
    
            if (ContextCompat.checkSelfPermission(MusicActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)!=
                    PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(MusicActivity.this,
                        new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
            }else {
                initMediaPlayer();//初始化mediaplayer
            }
    
        }
    
        private void initMediaPlayer() {
            try {
                mediaPlayer.setDataSource("/sdcard/music.mp3");//指定音频文件的路径
                mediaPlayer.prepare();//让mediaplayer进入准备状态
                mediaPlayer.setLooping(true);
                mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                    public void onPrepared(MediaPlayer mp) {
                        seekBar.setMax(mediaPlayer.getDuration());
                        musicLength.setText(format.format(mediaPlayer.getDuration())+"");
                        musicCur.setText("00:00");
                        musicName.setText("music.mp3");
                    }
                });
            } 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(MusicActivity.this,"denied access",Toast.LENGTH_SHORT).show();
                        finish();
                    }
                    break;
                default:
            }
        }
    
        @Override
        public void onClick(View view) {
            switch (view.getId()){
                case R.id.play:
                    if (!mediaPlayer.isPlaying()) {
                        mediaPlayer.start();//开始播放
                        mediaPlayer.seekTo(currentPosition);
    
                        //监听播放时回调函数
                        timer = new Timer();
                        timer.schedule(new TimerTask() {
    
                            Runnable updateUI = new Runnable() {
                                @Override
                                public void run() {
                                    musicCur.setText(format.format(mediaPlayer.getCurrentPosition())+"");
                                }
                            };
                            @Override
                            public void run() {
                                if(!isSeekBarChanging){
                                    seekBar.setProgress(mediaPlayer.getCurrentPosition());
                                    runOnUiThread(updateUI);
                                }
                            }
                        },0,50);
                    }
                    break;
                case R.id.pause:
                    if (mediaPlayer.isPlaying()) {
                        mediaPlayer.pause();//暂停播放
                    }
                    break;
                case R.id.stop:
                    Toast.makeText(MusicActivity.this,"停止播放",Toast.LENGTH_SHORT).show();
                    if (mediaPlayer.isPlaying()) {
                        mediaPlayer.reset();//停止播放
                        initMediaPlayer();
                    }
                    break;
                //音量加
                case R.id.volume_plus:
                    maxVolume = audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
                    audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC,AudioManager.ADJUST_RAISE,AudioManager.FLAG_SHOW_UI);
                    currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
                    Toast.makeText(MusicActivity.this,"音量增加,最大音量是：" + maxVolume + "，当前音量" + currentVolume,
                            Toast.LENGTH_SHORT).show();
                    break;
                //音量减
                case R.id.volume_decrease:
                    maxVolume = audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
                    audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC,AudioManager.ADJUST_LOWER,AudioManager.FLAG_SHOW_UI);
                    currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
                    Toast.makeText(MusicActivity.this,"音量减小,最大音量是：" + maxVolume + "，当前音量" + currentVolume,
                            Toast.LENGTH_SHORT).show();
                    break;
                default:
                    break;
            }
        }
    
        @Override
        protected void onDestroy() {
            super.onDestroy();
            isSeekBarChanging = true;
            if (mediaPlayer != null) {
                mediaPlayer.stop();
                mediaPlayer.release();
                mediaPlayer = null;
            }
            if (timer != null){
                timer.cancel();
                timer = null;
            }
        }
    
        /*进度条处理*/
        public class MySeekBar implements SeekBar.OnSeekBarChangeListener {
        
    
            public void onProgressChanged(SeekBar seekBar, int progress,
                                          boolean fromUser) {
            }
    
            /*滚动时,应当暂停后台定时器*/
            public void onStartTrackingTouch(SeekBar seekBar) {
                isSeekBarChanging = true;
            }
            /*滑动结束后，重新设置值*/
            public void onStopTrackingTouch(SeekBar seekBar) {
                isSeekBarChanging = false;
                mediaPlayer.seekTo(seekBar.getProgress());
            }
        }

**总结:** 就这样我们就使用MediaPlayer实现了简单的音乐播放器，能够播放、暂停、停止歌曲；同时使用SeekBar来控制音乐的播放进度，通过调节SeekBar的进度我们就可以实现播放进度的控制。

[SouthEast]: /images/20220608/8a92a4ace6384374a3a9f830f6729b1e.png