ContentResolver如何获取本地媒体文件

一 本地媒体文件的URI：

　　Android系统的ContentProvider提供的媒体文件信息都在"android.provider.MediaStore"类中

　　android.provider.MediaStore：该类封装了Audio，Files, Images, Video等媒体文件的URI信息和数据表结构信息

　　"红色"----表示媒体文件的类别   "黄色"----表示对应媒体文件操作的数据表

　　所有音乐文件的URI：MediaStore.Audio.Media.EXTERNAL_CONTENT_URI 实际值为：content://media/external/audio/media

      音乐文件对应专辑(Albums)URI : MediaStore.Audio.Albums.EXTERNAL_CONTENT_URI 实际值为：content://media/external/audio/albums

二 通过ContentResolver获取所用音乐文件

 

 1 public class LocalMusicUtil {
 2 
 3     private static final String TAG = LocalMusicUtil.class.getSimpleName();  
 4     /**
 5      * 获取本地所有的音乐文件
 6      */
 7     //表示操作的表  Uri.parse("content://media/external/audio/media");
 8     private static Uri uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;    
 9     //表示要获取的字段
10     private static String[] projection = new String[]{
11         String.valueOf(Media._ID),
12         Media.TITLE,
13         Media.ALBUM,
14         Media.ALBUM_ID,
15         Media.ARTIST,
16         Media.DURATION,
17         Media.DATA};
18     //表示where 子句
19     private static String selection = "mime_type in ('audio/mpeg','audio/x-ms-wma') and is_music>0 ";
20     //表示排序字段
21     private static String sortOrder = Media.DEFAULT_SORT_ORDER;
22     
23     public static ArrayList<Music> getLocalMusics(){
24         ArrayList<Music> musicList = new ArrayList<Music>();
25         ContentResolver content = MyApp.appContext.getContentResolver();
26         Cursor cursor = content.query(uri, projection, selection, null, sortOrder);
27         if(cursor==null){
28             Log.v(TAG, "Music corsor==null");
29         }else if(!cursor.moveToFirst()){
30             Log.v(TAG, "Music corsor.moveToForst() is false");
31         }else{
32             int idCol = cursor.getColumnIndex(Media._ID); 
33             int titleCol = cursor.getColumnIndex(Media.TITLE);
34             int albumCol = cursor.getColumnIndex(Media.ALBUM);
35             int albumIdCol = cursor.getColumnIndex(Media.ALBUM_ID);
36             int artistCol = cursor.getColumnIndex(Media.ARTIST); 
37              int durationCol = cursor.getColumnIndex(Media.DURATION);    
38              int dataCol = cursor.getColumnIndex(Media.DATA); 
39             do{
40                 int id = cursor.getInt(idCol);
41                 String title = cursor.getString(titleCol);
42                 String album = cursor.getString(albumCol);
43                 String albumImage = getAlbumImage(cursor.getString(albumIdCol));
44                 String artist = cursor.getString(artistCol);
45                 int duration = cursor.getInt(durationCol);
46                 String data = cursor.getString(dataCol);
47                 
48                 Music music = new Music();
49                 music.setId(id);
50                 music.setTitle(title);
51                 music.setAlbum(album);
52                 music.setAlbumImage(albumImage);
53                 music.setArtist(artist);
54                 music.setDuration(duration);
55                 music.setData(data);
56                 musicList.add(music);
57                 
58             }while(cursor.moveToNext());
59         }
60         cursor.close();
61         return musicList.size()==0?null:musicList;
62     }
63     
64     /**
65      * 通过专辑名id(albumId)获取专辑的图片地址
66      */
67     
68     public static String getAlbumImage(String  albumId){
69         String albumImage = "";
70         Cursor cursor = null;
71         try {
72             cursor = MyApp.appContext.getContentResolver().query(
73                     Uri.parse(MediaStore.Audio.Albums.EXTERNAL_CONTENT_URI+"/"+albumId), 
74                     new String[] { "album_art" }, 
75                     null, null, null);
76             for (cursor.moveToFirst(); !cursor.isAfterLast();) {
77                 albumImage = cursor.getString(0);
78                 break;
79             }
80         } catch (Exception e) {
81             e.printStackTrace();
82         } finally {
83             if (null != cursor) {
84                 cursor.close();
85             }
86         }
87         return albumImage;
88     }
89 }

 

 

 

　　

　　

posted on 2015-11-30 15:42  Jasonxcj  阅读(2791)  评论(0)  编辑  收藏  举报

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