音乐播放器请求写入外部存储权限？
Music Player asking for Write External Storage Permission?
我正在 Android 中创建一个音乐播放器应用程序。它工作正常但是每当我在歌曲列表中滚动时它开始崩溃并给出这个异常
Process: com.example.lenovo.musicplayer, PID: 31100
java.lang.SecurityException: External path: /storage/emulated/0/Android/data/com.android.providers.media/albumthumbs/1460104607336: Neither user 10294 nor current process has android.permission.WRITE_EXTERNAL_STORAGE.
at android.os.Parcel.readException(Parcel.java:1555)
at android.database.DatabaseUtils.readExceptionFromParcel(DatabaseUtils.java:190)
at android.database.DatabaseUtils.readExceptionWithFileNotFoundExceptionFromParcel(DatabaseUtils.java:153)
at android.content.ContentProviderProxy.openTypedAssetFile(ContentProviderNative.java:691)
at android.content.ContentResolver.openTypedAssetFileDescriptor(ContentResolver.java:1170)
at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:994)
at android.content.ContentResolver.openInputStream(ContentResolver.java:719)
at android.provider.MediaStore$Images$Media.getBitmap(MediaStore.java:1110)
at com.example.lenovo.musicplayer.Adapter.getView(Adapter.java:119)
at android.widget.AbsListView.obtainView(AbsListView.java:2571)
at android.widget.ListView.makeAndAddView(ListView.java:1894)
at android.widget.ListView.fillDown(ListView.java:710)
at android.widget.ListView.fillGap(ListView.java:674)
at android.widget.AbsListView.trackMotionScroll(AbsListView.java:5900)
at android.widget.AbsListView$FlingRunnable.run(AbsListView.java:5378)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:825)
at android.view.Choreographer.doCallbacks(Choreographer.java:619)
at android.view.Choreographer.doFrame(Choreographer.java:578)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:811)
at android.os.Handler.handleCallback(Handler.java:815)
at android.os.Handler.dispatchMessage(Handler.java:104)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:6102)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1028)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
当我在清单文件中授予写权限时，这个问题就消失了，但我不明白的是 为什么 它在我请求 WriteExternalStoragePermission不向任何类型的存储写入任何内容。
据我了解，音乐播放器不需要写入外部存储权限。
这是歌曲列表的代码Activity
public class ActivitySongsList extends AppCompatActivity {
public static ArrayList<MusicBean>songsList;
ListView listView;
Toolbar toolbar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_songs_list);
toolbar= (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
listView= (ListView) findViewById(R.id.lv_songs);
songsList=getAudioList();
Adapter adapter=new Adapter(this,songsList);
listView.setAdapter(adapter);
getSupportActionBar().setTitle("Songs");
toolbar.setTitleTextColor(Color.parseColor("#ffffff"));
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent=new Intent(ActivitySongsList.this,ActivityMusicDetails.class);
intent.putExtra("song",songsList.get(position));
intent.putExtra("position",String.valueOf(position));
startActivity(intent);
}
});
}
private ArrayList<MusicBean> getAudioList() {
ArrayList<MusicBean> musicBeanArrayList=new ArrayList<>();
try {
final Cursor mCursor = getContentResolver().query(
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
new String[]{MediaStore.Audio.Media.DISPLAY_NAME, MediaStore.Audio.Media.DATA, MediaStore.Audio.Media.ALBUM_ID,MediaStore.Audio.Media.ARTIST,MediaStore.Audio.Media.TITLE}, null, null,
"LOWER(" + MediaStore.Audio.Media.TITLE + ") ASC");
int count = mCursor.getCount();
int i = 0;
if (mCursor.moveToFirst()) {
do {
String song=mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE));
String path=mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
long album_id=mCursor.getLong(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM_ID));
String artist=mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));
Uri sArtworkUri = Uri
.parse("content://media/external/audio/albumart");
Uri albumArtUri = ContentUris.withAppendedId(sArtworkUri, album_id);
musicBeanArrayList.add(new MusicBean(song,path,albumArtUri.toString(),String.valueOf(album_id),artist));
/*songs[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME));
mAudioPath[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));*/
i++;
} while (mCursor.moveToNext());
}
mCursor.close();
}catch (Exception e)
{
e.printStackTrace();
}
return musicBeanArrayList;
}
}
它崩溃了，但这一行出现了异常
bitmap = MediaStore.Images.Media.getBitmap(ctx.getContentResolver(), uri);
在这段代码中，我获取了相应 mp3 文件的专辑封面。
但是这段代码也只是从外部存储中读取，因此这也不应该请求写入权限，因为我只是在读取位图而不是在写入它。
在清单文件中声明权限如下：
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
需要它是因为MediaStore需要它，没有READ-ONLY； MediaStore 正在根据您的行为访问外部文件，所以是您在阅读。
来自 the MediaProvider code，处理“/media/external/audio/albumart”
里面openFile(Uri uri, String mode)
try {
pfd = openFileAndEnforcePathPermissionsHelper(newUri, mode);
} catch (FileNotFoundException ex) {
// That didn't work, now try to get it from the specific file
pfd = getThumb(database, db, audiopath, albumid, null);
}
所以如果找不到文件，它会调用 getThumb
getThumb 呼叫 makeThumbInternal
然后在特定条件下，它调用
writeAlbumArt(need_to_recompress, out, compressed, bm);
在最新版本中，writeAlbumArt 调用
final long identity = Binder.clearCallingIdentity();
写之前，应该可以解决问题。但是修复是在 2015 年 8 月 27 日提交的，所以只有 Marshmallow 有机会获得修复。
你可以使用下面的link https://github.com/android/platform_packages_providers_mediaprovider/blob/master/src/com/android/providers/media/MediaProvider.java它会帮助你..
我正在 Android 中创建一个音乐播放器应用程序。它工作正常但是每当我在歌曲列表中滚动时它开始崩溃并给出这个异常
Process: com.example.lenovo.musicplayer, PID: 31100
java.lang.SecurityException: External path: /storage/emulated/0/Android/data/com.android.providers.media/albumthumbs/1460104607336: Neither user 10294 nor current process has android.permission.WRITE_EXTERNAL_STORAGE.
at android.os.Parcel.readException(Parcel.java:1555)
at android.database.DatabaseUtils.readExceptionFromParcel(DatabaseUtils.java:190)
at android.database.DatabaseUtils.readExceptionWithFileNotFoundExceptionFromParcel(DatabaseUtils.java:153)
at android.content.ContentProviderProxy.openTypedAssetFile(ContentProviderNative.java:691)
at android.content.ContentResolver.openTypedAssetFileDescriptor(ContentResolver.java:1170)
at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:994)
at android.content.ContentResolver.openInputStream(ContentResolver.java:719)
at android.provider.MediaStore$Images$Media.getBitmap(MediaStore.java:1110)
at com.example.lenovo.musicplayer.Adapter.getView(Adapter.java:119)
at android.widget.AbsListView.obtainView(AbsListView.java:2571)
at android.widget.ListView.makeAndAddView(ListView.java:1894)
at android.widget.ListView.fillDown(ListView.java:710)
at android.widget.ListView.fillGap(ListView.java:674)
at android.widget.AbsListView.trackMotionScroll(AbsListView.java:5900)
at android.widget.AbsListView$FlingRunnable.run(AbsListView.java:5378)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:825)
at android.view.Choreographer.doCallbacks(Choreographer.java:619)
at android.view.Choreographer.doFrame(Choreographer.java:578)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:811)
at android.os.Handler.handleCallback(Handler.java:815)
at android.os.Handler.dispatchMessage(Handler.java:104)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:6102)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1028)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
当我在清单文件中授予写权限时，这个问题就消失了，但我不明白的是 为什么 它在我请求 WriteExternalStoragePermission不向任何类型的存储写入任何内容。
据我了解，音乐播放器不需要写入外部存储权限。
这是歌曲列表的代码Activity
public class ActivitySongsList extends AppCompatActivity {
public static ArrayList<MusicBean>songsList;
ListView listView;
Toolbar toolbar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_songs_list);
toolbar= (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
listView= (ListView) findViewById(R.id.lv_songs);
songsList=getAudioList();
Adapter adapter=new Adapter(this,songsList);
listView.setAdapter(adapter);
getSupportActionBar().setTitle("Songs");
toolbar.setTitleTextColor(Color.parseColor("#ffffff"));
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent=new Intent(ActivitySongsList.this,ActivityMusicDetails.class);
intent.putExtra("song",songsList.get(position));
intent.putExtra("position",String.valueOf(position));
startActivity(intent);
}
});
}
private ArrayList<MusicBean> getAudioList() {
ArrayList<MusicBean> musicBeanArrayList=new ArrayList<>();
try {
final Cursor mCursor = getContentResolver().query(
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
new String[]{MediaStore.Audio.Media.DISPLAY_NAME, MediaStore.Audio.Media.DATA, MediaStore.Audio.Media.ALBUM_ID,MediaStore.Audio.Media.ARTIST,MediaStore.Audio.Media.TITLE}, null, null,
"LOWER(" + MediaStore.Audio.Media.TITLE + ") ASC");
int count = mCursor.getCount();
int i = 0;
if (mCursor.moveToFirst()) {
do {
String song=mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE));
String path=mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
long album_id=mCursor.getLong(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM_ID));
String artist=mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));
Uri sArtworkUri = Uri
.parse("content://media/external/audio/albumart");
Uri albumArtUri = ContentUris.withAppendedId(sArtworkUri, album_id);
musicBeanArrayList.add(new MusicBean(song,path,albumArtUri.toString(),String.valueOf(album_id),artist));
/*songs[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME));
mAudioPath[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));*/
i++;
} while (mCursor.moveToNext());
}
mCursor.close();
}catch (Exception e)
{
e.printStackTrace();
}
return musicBeanArrayList;
}
}
它崩溃了，但这一行出现了异常
bitmap = MediaStore.Images.Media.getBitmap(ctx.getContentResolver(), uri);
在这段代码中，我获取了相应 mp3 文件的专辑封面。 但是这段代码也只是从外部存储中读取，因此这也不应该请求写入权限，因为我只是在读取位图而不是在写入它。
在清单文件中声明权限如下：
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
需要它是因为MediaStore需要它，没有READ-ONLY； MediaStore 正在根据您的行为访问外部文件，所以是您在阅读。
来自 the MediaProvider code，处理“/media/external/audio/albumart”
里面openFile(Uri uri, String mode)
try {
pfd = openFileAndEnforcePathPermissionsHelper(newUri, mode);
} catch (FileNotFoundException ex) {
// That didn't work, now try to get it from the specific file
pfd = getThumb(database, db, audiopath, albumid, null);
}
所以如果找不到文件，它会调用 getThumb
getThumb 呼叫 makeThumbInternal
然后在特定条件下，它调用
writeAlbumArt(need_to_recompress, out, compressed, bm);
在最新版本中，writeAlbumArt 调用
final long identity = Binder.clearCallingIdentity();
写之前，应该可以解决问题。但是修复是在 2015 年 8 月 27 日提交的，所以只有 Marshmallow 有机会获得修复。
你可以使用下面的link https://github.com/android/platform_packages_providers_mediaprovider/blob/master/src/com/android/providers/media/MediaProvider.java它会帮助你..