Android 音乐播放器 - HelloWorld开发者社区

国庆七天没有更新博客，今天第一天上班就来了。

想了很久不知道写什么，突然想了最近在做的项目要用的一个功能（利用contentProvider来扫描内存卡上的音频文件），速度相当给力，300首歌一秒钟都不到。废话不多说，上代码吧！

主界面：

public class MainActivity extends Activity {

   private ListView listview;
   private List data;
   private BaseAdapter adapter ;

   private RelativeLayout root ;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
       root = (RelativeLayout) findViewById(R.id.root) ;
       data = ReadDataFromContentProvider.readAudio(this) ;
       if(null == data || data.size() == 0) {
           Toast.makeText(this, "没有扫描到音频文件!", Toast.LENGTH_LONG).show() ;
           return ;
       }
       listview = (ListView) findViewById(R.id.listview) ;
       adapter = new AudioAdapter(this, data) ;
       listview.setAdapter(adapter) ;
       listview.setOnItemClickListener(new OnItemClickListener() {

           @Override
           public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                   long arg3) {
               // 获取专辑图片
               Bitmap bmp = data.get(arg2).getAlbumCover() ;
               if(null != bmp) {
                   BitmapDrawable drawable = new BitmapDrawable(getResources(), bmp) ;
                   root.setBackgroundDrawable(drawable);
               }
               else {
                   root.setBackgroundColor(Color.GRAY) ;
               }
           }
       }) ;

       ReadDataFromContentProvider.readImage(this) ;
}
}

class AudioAdapter extends BaseAdapter {
private Context context ;
private List data ;

   public AudioAdapter(Context context, List data) {
       super();
       this.context = context;
       this.data = data;
   }

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

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

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

   @Override
   public View getView(int position, View convertView, ViewGroup parent) {
       View view ;
       if(null != convertView) {
           view = convertView ;
       }
       else {
           view = LayoutInflater.from(context).inflate(android.R.layout.simple_list_item_2, null) ;
       }
       TextView tv1 = (TextView) view.findViewById(android.R.id.text1) ;
       tv1.setText(data.get(position).getTitle()) ;
       TextView tv2 = (TextView) view.findViewById(android.R.id.text2) ;
       tv2.setText(data.get(position).getArtist() + "\t" + data.get(position).getAlbum()) ;
       return view;
   }

}

实体类：

public class MyAudio {
   private String title , path , artist , album ;
   private long duration ;
   private Bitmap albumCover ;

   public MyAudio(String title, String path, String artist, String album , long duration) {
       super();
       this.title = title;
       this.path = path;
       this.artist = artist;
       this.album = album;
       this.duration = duration ;
   }
   public MyAudio(String title, String path, String artist, String album , long duration , Bitmap albumCover) {
       super();
       this.title = title;
       this.path = path;
       this.artist = artist;
       this.album = album;
       this.duration = duration ;
       this.albumCover = albumCover ;
   }

   public String getTitle() {
       return title;
   }

   public void setTitle(String title) {
       this.title = title;
   }

   public String getPath() {
       return path;
   }

   public void setPath(String path) {
       this.path = path;
   }

   public String getArtist() {
       return artist;
   }

   public void setArtist(String artist) {
       this.artist = artist;
   }

   public String getAlbum() {
       return album;
   }

   public void setAlbum(String album) {
       this.album = album;
   }

   public long getDuration() {
       return duration;
   }
   public void setDuration(long duration) {
       this.duration = duration;
   }

   public Bitmap getAlbumCover() {
       return albumCover;
   }
   @Override
   public String toString() {
       return "MyAudio [title=" + title + ", path=" + path + ", artist="
               + artist + ", album=" + album + ", duration=" + duration
               + ", albumCover=" + albumCover + "]";
}
}

工具类：

public class ReadDataFromContentProvider {

   public static void readImage(Context context) {
       ContentResolver resolver = context.getContentResolver() ;
       Uri imgUri = Images.Media.EXTERNAL_CONTENT_URI ;
       String[] columns = new String[]{
               Images.Media.TITLE ,
               Images.Media.DATA ,
               Images.Media.SIZE ,
               Images.Media.MIME_TYPE   // 类型
       };
       Cursor cursor = resolver.query(imgUri, columns, null, null, null) ;
       if(null != cursor && cursor.getCount() > 0) {
           while(cursor.moveToNext()) {
               Log.e("imgs" , cursor.getString(0) + "\t" + cursor.getString(3)) ;
           }
       }
       if(null != cursor) {
           cursor.close() ;
       }
   }

   public static List readAudio(Context context) {
       ContentResolver resolver = context.getContentResolver() ;
       Uri audioUri = Audio.Media.EXTERNAL_CONTENT_URI ;
       String[] columns = {
               Audio.Media.TITLE ,    // 歌名
               Audio.Media.DATA ,    // 路径
               Audio.Media.ARTIST ,    // 演唱者
               Audio.Media.ALBUM   ,   // 专辑名
               Audio.Media.DURATION ,    // 音频文件长度，毫秒
               Audio.Media.ALBUM_KEY     // 用来读取专辑图片时使用

       };
       List data = null ;
       Cursor cursor = resolver.query(
               audioUri,
               columns,
               //null, null,
               Audio.Media.DATA + " like ? or " + Audio.Media.DATA + " like ?" , new String[]{"%.mp3" , "%.wma"} ,
               null) ;
       if(null != cursor && cursor.getCount() > 0) {
           data = new ArrayList() ;
           while(cursor.moveToNext()) {
               // 读到一个音频
               /////////////////// 读取该音频的专辑图片信息
               Bitmap bmp = null ;
               String albumKey = cursor.getString(5) ;
               Uri albumUri = Audio.Albums.EXTERNAL_CONTENT_URI ;
               Cursor albumCursor = resolver.query(albumUri, new String[]{Audio.Albums.ALBUM_ART}, Audio.Albums.ALBUM_KEY +"=?", new String[]{albumKey}, null) ;
               if(albumCursor != null && albumCursor.getCount() > 0) {
                   albumCursor.moveToNext() ;
                   String albumPath = albumCursor.getString(0);
                   bmp = BitmapFactory.decodeFile(albumPath) ;
                   albumCursor.close() ;
               }
               //////////////////
               data.add(new MyAudio(cursor.getString(0), cursor.getString(1), cursor.getString(2), cursor.getString(3) , cursor.getLong(4) , bmp)) ;
           }
       }
       if(null != cursor) {
           cursor.close() ;
       }
       return data ;
   }
}