Android带播放进度条的音乐播放器

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：

1. 第一步

布局文件activity_main.xml

<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。