Android：音乐播放器（3）—从播放列表到播放歌曲

播放列表

播放列表布局

播放列表代码

1.MusicMedia 类

public class MusicMedia {

    private int id;    //音乐id
    private String title;  //音乐标题
    private String artist;//音乐作者
    private String url; //音乐存放路径
    private String time; //音乐时长
    private String size; //音乐大小
    private int albumId; //专辑id
    private String album; //专辑

    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getTitle() {
        return title;
    }
    public void setTitle(String title) {
        this.title = title;
    }
    public String getArtist() {
        return artist;
    }
    public void setArtist(String artist) {
        this.artist = artist;
    }
    public String getUrl() {
        return url;
    }
    public void setUrl(String url) {
        this.url = url;
    }
    public String getTime() {
        return time;
    }
    //修改时间格式
    public void setTime(int time) {
        time /= 1000;
        int minute = time / 60;
        int hour = minute / 60;
        int second = time % 60;
        minute %= 60;
        this.time = String.format("%02d:%02d", minute, second);
    }
    public String getSize() {
        return size;
    }
    public void setSize(Long size) {
        long kb = 1024;
        long mb = kb * 1024;
        long gb = mb * 1024;
        if (size >= gb) {
            this.size = String.format("%.1f GB", (float) size / gb);
        } else if (size >= mb) {
            float f = (float) size / mb;
            this.size = String.format(f > 100 ? "%.0f MB" : "%.1f MB", f);
        } else if (size >= kb) {
            float f = (float) size / kb;
            this.size = String.format(f > 100 ? "%.0f KB" : "%.1f KB", f);
        } else
            this.size = String.format("%d B", size);
    }
    public int getAlbumId() {
        return albumId;
    }
    public void setAlbumId(int albumId) {
        this.albumId = albumId;
    }
    public String getAlbum() {
        return album;
    }
    public void setAlbum(String album) {
        this.album = album;
    }
}

2.Main4Activity代码

public class Main4Activity extends AppCompatActivity {

    private ListView listView;
    private List list=new ArrayList<>();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main4);
        listView= (ListView) findViewById(R.id.listView);
        getList();
        listView.setAdapter(new MyAdapter());
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView parent, View view, int position, long id) {
                Intent intent=new Intent(Main4Activity.this,Main3Activity.class);
                intent.putExtra("url",list.get(position).getUrl());
                startActivity(intent);
            }
        });
    }
    public  void getList(){
      /*加载本地音乐文件库需要加READ_EXTERNAL_STORAGE权限
                查询媒体数据库的uri
        视频：MediaStore.Video.Media.EXTERNAL_CONTENT_URI
        图片：MediaStore.Images.Media.EXTERNAL_CONTENT_URI
        音乐（SD卡）：MediaStore.Audio.Media.EXTERNAL_CONTENT_URI
        音乐（手机内部）：MediaStore.Audio.Media.INTERNAL_CONTENT_URI
        */

        ContentResolver contentResolver=getContentResolver();
       Cursor cursor= contentResolver.query(MediaStore.Audio.Media.INTERNAL_CONTENT_URI,null,null,null,MediaStore.Audio.Media.DEFAULT_SORT_ORDER);
        while(cursor!=null){
            while (cursor.moveToNext()){
                int id = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media._ID));
                //歌曲标题
                String title = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE));
                //歌曲的专辑名：MediaStore.Audio.Media.ALBUM
                String album = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM));
                int albumId = cursor.getInt(cursor.getColumnIndex(MediaStore.Audio.Media.ALBUM_ID));
                //歌曲的歌手名： MediaStore.Audio.Media.ARTIST
                String artist = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));
                //歌曲文件的路径 ：MediaStore.Audio.Media.DATA
                String url = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
                //歌曲的总播放时长 ：MediaStore.Audio.Media.DURATION
                int duration = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION));
                //歌曲文件的大小 ：MediaStore.Audio.Media.SIZE
                Long size = cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));

                MusicMedia musicMedia = new MusicMedia();
                musicMedia.setId(id);
                musicMedia.setArtist(artist);
                musicMedia.setSize(size);
                musicMedia.setTitle(title);
                musicMedia.setTime(duration);
                musicMedia.setUrl(url);
                musicMedia.setAlbum(album);
                musicMedia.setAlbumId(albumId);

                list.add(musicMedia);
            }
        }
    }
    class MyAdapter extends BaseAdapter{

        @Override
        public int getCount() {
            return  list.size();
        }

        @Override
        public Object getItem(int position) {
            return list.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            TextView textView ;
            if(convertView==null){
                textView = new TextView(Main4Activity.this);
            }else{
                textView = (TextView) convertView;
            }
            textView.setText(list.get(position).getTitle());
            return textView;
        }
    }
}

3.Main3Activity代码 跳转播放页面代码

public class Main3Activity extends AppCompatActivity {
    private Button start,end,pause;
    MediaPlayer mediaPlayer;
    private SeekBar seekBar;
    Timer timer = new Timer();;
    TimerTask timerTask;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main3);

        start = (Button) findViewById(R.id.start);
        end = (Button) findViewById(R.id.end);
        pause = (Button) findViewById(R.id.pause);
        seekBar = (SeekBar) findViewById(R.id.seekBar);



        Intent intent = getIntent();
        String url = intent.getStringExtra("url");
        mediaPlayer = MediaPlayer.create(Main3Activity.this, Uri.parse(url));


        //歌曲的播放时长
        seekBar.setMax(mediaPlayer.getDuration());

        seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int i, boolean b) {

            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {
                Log.i("messgae","start");

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                Log.i("messgae","stop");

                //设置歌曲的进度为进度条的位置
                mediaPlayer.seekTo(seekBar.getProgress());

            }
        });
    }

    public void click(View view){

        int id = view.getId();

        switch(id){
            case R.id.start:
                start();

                break;
            case R.id.end:

                stop();

                break;
            case R.id.pause:
                pause();
                break;
        }
    }
    public void start(){
        mediaPlayer.start();
        timerTask = new TimerTask() {
            @Override
            public void run() {
                //歌曲当前播放位置
                seekBar.setProgress(mediaPlayer.getCurrentPosition());
            }
        };

        //1.等多久再执行什么
        //2.每隔多久执行一次什么
        timer.schedule(timerTask,0,100);


        start.setEnabled(false);
    }
    public void pause(){
        String pause1 = pause.getText().toString().trim();
        if("暂停".equals(pause1)){
            mediaPlayer.pause();
            pause.setText("继续");
        }else{
            mediaPlayer.start();
            pause.setText("暂停");
        }


    }
    public void stop(){
        if(mediaPlayer!=null){
            timer.cancel();
            mediaPlayer.stop();
            mediaPlayer.release();
            mediaPlayer = null;
            start.setEnabled(true);
        }
    }
}

注：调试时，需要真机！！因为用的手机默认音乐