[求助]用ContentResolver取不到MediaStore里的内容

Question

代码如下:
ContentResolver cr =this.getContentResolver();                
                Cursor tempCur = cr.query(
                                MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
                                /*new String[]{
                                                MediaStore.Audio.Media._ID, //int
                                                MediaStore.Audio.Media.DATA, //String 
                                                MediaStore.Audio.Media.DISPLAY_NAME, //String
                                                MediaStore.Audio.Media.MIME_TYPE //String
                                        }*/
                                null,//无论取null还是上边的数组都是一样的
                                null, null, MediaStore.Audio.Media.DEFAULT_SORT_ORDER); //order取null也是一样的
                 
                 
                if(tempCur!=null){
                        if(D)Log.d(TAG,"Cursor.getCount in Audio"+tempCur.getCount());
                }else{
                        if(D)Log.d(TAG,"Cursor.getCount in Audio is NULL");
                }manifest 权限 :<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>在我自己的手机上调试 moto defy+ (因为虚拟机里木有多媒体文件...懒得弄...)
手机里有一堆歌...catlog:
06-27 23:29:38.139: D/Puzzle_Config(16872): Cursor.getCount in Audio is NULL
肿么破...

Answer 1

你截取log不全~     打印cr和tempCur是否为null

Answer 2

if(cr!=null){
if(D)Log.d(TAG,"ContentResolver is "+cr.toString());
}else{
if(D)Log.d(TAG,"ContentResolver is NULL");
}
if(tempCur!=null){
if(D)Log.d(TAG,"Cursor.getCount in Audio"+tempCur.getCount());
}else{
if(D)Log.d(TAG,"Cursor in Audio is NULL");
}06-28 11:26:28.030: D/Puzzle_Config(18425): ContentResolver is android.app.ContextImpl$ApplicationContentResolver@40501910
06-28 11:26:28.030: D/Puzzle_Config(18425): Cursor in Audio is NULL
cr不是NULL
tempCur是NULL

Answer 3

URI是MediaStore类里提供的静态变量 应该是错不了=.=

Answer 4

06-28 12:00:57.171: D/Puzzle_Config(18959): URI : content://media/external/audio/media

Answer 5

例如
MediaStore.Audio.Media.DATA= “data”
MediaStore.Audio.Media.DISPLAY_NAME=“displayName”
MediaStore.Audio.Media.MIME_TYPE=“mimeType”/*new String[]{
                                                MediaStore.Audio.Media._ID, //int
                                                MediaStore.Audio.Media.DATA, //String 
                                                MediaStore.Audio.Media.DISPLAY_NAME, //String
                                                MediaStore.Audio.Media.MIME_TYPE //String
                                        }*/修改成new String[]{
"_id","data,"displayName","mimeType"
}

Answer 6

例如 MediaStore.Audio.Media.DATA= “data” MediaStore.Audio.Media.DISPLAY_NAME=“displayName” MediaStore.Audio.Media.MIME_TYPE=“mimeType” /*new String[]{                                            ……
额...不是这里的问题...我发现是我犯了个相当2的错误=.=  不过还是谢谢了
，也范啦这个问题，不知道怎么解决，你是怎么弄的