【发布时间】：2015-02-14 17:38:00
【问题描述】：
我正在尝试获取设备中的音乐文件。这是我的工作：
public ArrayList<Track> getAllSongsFromSDCARD()
{
allTracks = new ArrayList<Track>();
String[] STAR = { "*" };
Uri allsongsuri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
String selection = MediaStore.Audio.Media.IS_MUSIC + " != 0";
Cursor cursor = mContext.getApplicationContext().getContentResolver().query(allsongsuri, STAR, selection, null, null);
if (cursor != null) {
if (cursor.moveToFirst()) {
do {
String song_name = cursor
.getString(cursor
.getColumnIndex(MediaStore.Audio.Media.DISPLAY_NAME));
int song_id = cursor.getInt(cursor
.getColumnIndex(MediaStore.Audio.Media._ID));
String fullpath = cursor.getString(cursor
.getColumnIndex(MediaStore.Audio.Media.DATA));
String album_name = cursor.getString(cursor
.getColumnIndex(MediaStore.Audio.Media.ALBUM));
int album_id = cursor.getInt(cursor
.getColumnIndex(MediaStore.Audio.Media.ALBUM_ID));
String artist_name = cursor.getString(cursor
.getColumnIndex(MediaStore.Audio.Media.ARTIST));
int artist_id = cursor.getInt(cursor
.getColumnIndex(MediaStore.Audio.Media.ARTIST_ID));
String duration = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Media.DURATION));
int[] splitTime = null;
String hours, minutes, seconds, formattedTime;
try{
splitTime = splitToComponentTimes(BigDecimal.valueOf(Long.valueOf(duration)/1000));
hours = String.valueOf(splitTime[0]);
minutes = String.valueOf(splitTime[1]);
seconds = String.valueOf(splitTime[2]);
if(hours.equals("0")){
formattedTime = minutes + ":" + seconds;
}else{
formattedTime = hours + ":" + minutes + ":" + seconds;
}
}catch (Exception e){
formattedTime = "00:00";
}
allTracks.add(new Track(song_name, song_id, fullpath, album_name, album_id, artist_name, artist_id, formattedTime));
} while (cursor.moveToNext());
}
sortTracksAlphabetically(allTracks);
cursor.close();
}
return allTracks;
}
我的清单中有以下权限：
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
当我在装有 Android 4.3 的设备上运行该代码时，它运行良好。但是当我在 Android 5.0.2 的设备上运行它时，它会给出
"java.lang.SecurityException: Permission Denial: 读取 com.android.providers.media.MediaProvider URI content://media/external/audio/media from pid=5701, uid=10054 需要 android.permission.READ_EXTERNAL_STORAGE"
谁能告诉我为什么？这是完整的堆栈跟踪：
02-14 19:25:52.812 5701-5701/com.yrazlik.musicplayer E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.yrazlik.musicplayer, PID: 5701
java.lang.SecurityException: Permission Denial: reading com.android.providers.media.MediaProvider uri content://media/external/audio/media from pid=5701, uid=10054 requires android.permission.READ_EXTERNAL_STORAGE, or grantUriPermission()
at android.os.Parcel.readException(Parcel.java:1540)
at android.database.DatabaseUtils.readExceptionFromParcel(DatabaseUtils.java:185)
at android.database.DatabaseUtils.readExceptionFromParcel(DatabaseUtils.java:137)
at android.content.ContentProviderProxy.query(ContentProviderNative.java:420)
at android.content.ContentResolver.query(ContentResolver.java:478)
at android.content.ContentResolver.query(ContentResolver.java:422)
at com.yrazlik.musicplayer.dialogs.AllSongsDialog.getAllSongsFromSDCARD(AllSongsDialog.java:74)
at com.yrazlik.musicplayer.dialogs.AllSongsDialog.onCreate(AllSongsDialog.java:59)
at android.app.Dialog.dispatchOnCreate(Dialog.java:373)
at android.app.Dialog.show(Dialog.java:274)
at com.yrazlik.musicplayer.fragments.PlaylistFragment$1.onClick(PlaylistFragment.java:86)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
谢谢。
【问题讨论】：
-
确保您的
<uses-permission>元素位置正确。他们需要是<manifest>的直系子级，作为<application>的同龄人。 -
@CommonsWare 哦，你是对的，我已经将权限放在应用程序标签中，现在我移动了它们。现在它起作用了。但是为什么我的android 4.3设备没有问题，但5.0.2设备有问题？