1、Android R获取专辑图

因为Android存储策略升级，不可使用常规方法访问Android/data来获取专辑图，因此使用以下新代码：

//常规
String mUriAlbums = "content://media/external/audio/albums";
            String[] projection = new String[]{"album_art"};

            Cursor cur = context.getContentResolver().query(
                    Uri.parse(mUriAlbums + "/" + albumId),
                    projection, null, null, null);
            String album_art = null;
            if (cur.getCount() > 0 && cur.getColumnCount() > 0) {
                cur.moveToNext();
                album_art = cur.getString(0);
                Log.d("getalbum", "getAlbumArt: "+ album_art + "*" + cur.getString(0));
            }
            cur.close();
            cur = null;

            return BitmapFactory.decodeFile(album_art);
//Android R新方法（待优化）
MediaMetadataRetriever mmr = new MediaMetadataRetriever();//主要1
        Log.d(TAG, "path:" + mediaPath);
        try
        {
            mmr.setDataSource(mediaPath);//主要2
            

            byte[] pic = mmr.getEmbeddedPicture();  //主要3

            Bitmap songalbum = null;
            songalbum = BitmapFactory.decodeByteArray(pic,0,pic.length);//主要4
            Log.d(TAG,"picture:"+ songalbum.getWidth() + "x" + songalbum.getHeight());
            
            return songalbum;
        }

        catch (Exception e)
        {
            e.printStackTrace();
            mmr.setDataSource(mediaPath);
            Bitmap songalbum = null;
            songalbum = BitmapFactory.decodeResource(context.getResources(), R.drawable.music_default_album);
            
            return songalbum ;
        }
    }