我有问题,FIleObserver和ContentObserver都无法在
Android Marshmallow中运行.我正在使用这个东西来检测文件夹内发生的变化.我为marshmallow设置了运行时权限.但在那之后它也没有显示任何事件.它在其他版本中完美运行.请帮我解决这个问题.
首先,我尝试在Service中使用Content Resolver来检测后台中的文件夹更改.
public class TestService extends Service {
@Override
public void onCreate() {
super.onCreate();
}
@Override
public int onStartCommand(Intent intent,int flags,int startId) {
initial();
return START_STICKY;
}
public void initial(){
getContentResolver().registerContentObserver(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI,true,new ContentObserver(new Handler()) {
@Override
public boolean deliverSelfNotifications() {
Log.d("hai","deliverSelfNotifications");
return super.deliverSelfNotifications();
}
@Override
public void onChange(boolean selfChange) {
super.onChange(selfChange);
}
@Override
public void onChange(boolean selfChange,Uri uri) {
if (uri.toString().matches(MediaStore.Images.Media.EXTERNAL_CONTENT_URI.toString() + "/[0-9]+")) {
Cursor cursor = null;
try {
cursor = getContentResolver().query(uri,new String[] {
MediaStore.Images.Media.DISPLAY_NAME,MediaStore.Images.Media.DATA
},null,null);
if (cursor != null && cursor.moveToFirst()) {
final String fileName = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DISPLAY_NAME));
final String path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
// TODO: apply filter on the file name to ensure it's screen shot event
Log.d("file","FILE CHANGE OCCURED " + fileName + " " + path);
}
} finally {
if (cursor != null) {
cursor.close();
}
}
}
super.onChange(selfChange,uri);
}
}
);
}
}
并运行时权限为：
private void getPermission(){
boolean hasPermission = (ContextCompat.checkSelfPermission(this,Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED);
if (!hasPermission) {
ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},REQUEST_READ_STORAGE);
}
}
并获得了权限导致onRequestPermissionsResult.
这种方法对我不起作用.所以我在该服务中尝试使用FileObserver.那个时候它也适用于所有其他平台,但不适用于Marshmallow.
