1600802120

 　　1.实现的功能

　　1.音乐播放器的前一首，下一首，暂停，播放功能。

　　

• 2.对音乐播放器界面截图
• 

   

  
  

   

  
  

   

  
  

   

  .将其中的关键代码放置自己的博客，比如：播放功能的代码

1.上一首下一首切换，暂停播放

private void changeMusic(int position) {//切歌
    if (position < 0) {
        musicposition = position = list1.size() - 1;

    } else if (position > list1.size() - 1) {
        musicposition = position = 0;
    }

    if (mediaPlayer == null) {
        mediaPlayer = new MediaPlayer();
    }
    try {
        mediaPlayer.reset();
        mediaPlayer.setDataSource(list1.get(position).path);
        mediaPlayer.prepare();
        mediaPlayer.start();
    } catch (IOException e) {
        e.printStackTrace();
    }

}
public void onClick(View v) {

    switch (v.getId()) {
        case R.id.play:
            if (!mediaPlayer.isPlaying()) {
                changeMusic(0);
            }
            break;
        case R.id.pause:
            if (mediaPlayer.isPlaying()) {
                mediaPlayer.pause();
            }
            break;
        case R.id.stop:
            if (mediaPlayer.isPlaying()) {
                mediaPlayer.reset();//停止播放

            }
            break;
        case R.id.next:
        {
            changeMusic(++musicposition);


            ;}

        break;


        case R.id.last:
            changeMusic(--musicposition);
            break;
    }
}

 2.扫描sd卡并得到音乐文件

mListView = (ListView) findViewById(R.id.list1);
list1 = new ArrayList<>();
//把扫描到的音乐赋值给list
list1 = adpter2.getMusicData(this);

public static List<musiclist> getMusicData(Context context) {
    List<musiclist>list = new ArrayList<musiclist>();
    Cursor cursor = context.getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null,
            null, MediaStore.Audio.AudioColumns.IS_MUSIC);
    if (cursor != null) {
        while (cursor.moveToNext()) {
            musiclist song = new musiclist();
            song.song = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME));
            song.path = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
            song.size = cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));
                list.add(song);
        }
        cursor.close();
    }
    return list;
}

 3.通过适配器输出音乐文件属性

adapter = new Adapter1(this, list1);
        mListView.setAdapter(adapter);

public class Adapter1 extends BaseAdapter {
    private Context context;
    private List<musiclist> list;

    public Adapter1(MainActivity mainActivity, List<musiclist> list) {
        this.context = mainActivity;
        this.list = list;

    }

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

    public Object getItem(int i) {
        return list.get(i);
    }

    public long getItemId(int i) {
        return i;
    }

    public View getView(final int i, View view, ViewGroup viewGroup) {
        ViewHolder holder = null;
        if (view == null) {
            holder = new ViewHolder();
            view = View.inflate(context, R.layout.list1, null);
            holder.song = (TextView) view.findViewById(R.id.text1);
            holder.position = (TextView) view.findViewById(R.id.text4);
            view.setTag(holder);
        } else {
            holder = (ViewHolder) view.getTag();
        }
        holder.song.setText(list.get(i).song.toString());
        holder.position.setText(i+1+"");

        return view;
    }
    class ViewHolder{
        TextView song;
        TextView position;

    }

}

4.对listview的是否点击和是否播放的添加监听器

 mediaPlayer.setOnCompletionListener( this);
        mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {

                musicposition = position;
                changeMusic(musicposition);

            }
        });
    }

　　

　　

4.代码链接  https://git.coding.net/ahabbw/android12.git

5.apk的下载地址  https://git.coding.net/ahabbw/android12.git