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How to delete files from media content providers on android N

This code worked on previous versions of android, but no longer seems to work on N.
I want to delete a media file, given the content URI of the file. I query the content provider for the path of the file. On android N, this seems to return a filename of the following form:
/storage/1143-1403/DCIM/Camera/20171019_185604.mp4
On previous versions of Android, the path would been a direct path to the SD Card. (And the real file can actually be found in the /sdcard/DCIM/Camera directory).
The problem: when I call new File(path).delete(), the delete fails. It succeeds in previous versions of Android.
Manifest permissions are:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_INTERNAL_STORAGE" />
I have requested the following permissions, and they have been granted:
Manifest.permission.WRITE_EXTERNAL_STORAGE,
Manifest.permission.READ_EXTERNAL_STORAGE,
...
Manifest.permission.MODIFY_AUDIO_SETTINGS,
There is no Manifest.permission flag for WRITE_INTERNAL_STORAGE.
I'm guessing "/storage/1143-1403/DCIM/Camera" is some kind of fused file system.
Calling file = file.getAbsoluteFile().getCanonicalFile(); does not change the path or otherwise improve the situtation.

How to use setImageDrawable() with image paths. ANDROID

I am trying to put an image in an imageView by code. I have some images in the Drawable directory but, with other images, I have to use the internal storage. In first case,
holder.picture.setImageDrawable(getResources().getDrawable(R.drawable.my_image));
works but, in the second case, Android give me this error:
BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /storage/emulated/0/Sensia_Sniffer/18_04_2018/18_56_18_photo.JPEG (No such file or directory)
and I don't know why. I am using this lines:
Drawable drawable = Drawable.createFromPath(my_image_path);
holder.picture.setImageDrawable(drawable);
and in AndroidManifest.xml I have this permissions:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
Could you help me with this?
Thank you very much!!!

You forgot to ask for runtime permissions for the requested permissions in manifest file.
Needed for Android 6+.

android APN How to read and write it?

i work on a app (> 4.4) and my boss would like to save the configuration of the APN into the SQLite (our database).
As this, if the APN is lost for a reason we can retrieve easily these information and configure it ..
well, i've try some code but actually NOTHING work ...
I have this error message
Java.Lang.SecurityException: No permission to write APN settings: Neither user 10081 nor current process has android.permission.WRITE_APN_SETTINGS.
Of course, i have added to the manifest the correct RIGTH as this
<uses-permission android:name="android.permission.READ_APN_SETTINGS"></uses-permission>
<uses-permission android:name="android.permission.WRITE_APN_SETTINGS"></uses-permission>
<uses-feature android:name="android.hardware.telephony" android:required="false" />
And here is it my code, it's with xamarin android but if you have some code with android , no matter i can find the translatation ..
Android.Net.Uri APN_TABLE_URI = Android.Net.Uri.Parse("content://telephony/carriers");
//path to preffered APNs
Android.Net.Uri PREFERRED_APN_URI = Android.Net.Uri.Parse("content://telephony/carriers/preferapn");
//
Android.Database.ICursor cursor = ctx.ContentResolver.Query(PREFERRED_APN_URI, null, null, null, null);
Thanks guys for all your time you spend here for to share your knowledge

try to add these two permissions:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

Can't Read Files in Sdcard in emulator

I have some problems in my App.
I just wanna read file in sdcard, so I put the file in /storage/sdcard/abcd (the folder I made by adb) in emulator.
File name is "1.14P", and I verify it is in that path. Its permission is 770.
But my problem is, I can't access sdcard by Application.
sampleFile = new File (Environment.getExternalStorageDirectory(), "abcd/1.14P");
sampleFile.exists() //return false
sampleFile2 = new File (Environment.getExternalStorageDirectory(), "tttt");
sampleFile2.mkdir() //return false
Sdcard is mounted well, I thought.
String state = Environment.getExternalStorageState(); //return "mounted"
I give the permission but I can't access to sdcard. Here is my manifest.xml. (part)
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.hu.test004" >
<uses-permission android:name="ANDROID.PERMISSION.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="ANDROID.PERMISSION.READ_EXTERNAL_STORAGE"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
...(Activities)
I can't understand why it happens. Please give me some favor. Thanks.

SOLVED::I've got it!
The problem is, I declared permissions in capital letter, so App doesn't grant permissions.
I change
<uses-permission android:name="ANDROID.PERMISSION.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="ANDROID.PERMISSION.READ_EXTERNAL_STORAGE"/>
to
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
and permission granted.
Thank you for your favor all.

I think the "," is part of the problem. The other is the "exists()" is for directories, not files.
See here:
new File(path) always actually creates a file on android?
contrary to the docs:
http://developer.android.com/reference/java/io/File.html
you may want to use isFile() instead.

Could you try adding "/" in front of your names??
e.g. "/abcd/1.14P"

Why Images.Media.insertImage doesn't require WRITE_EXTERNAL_STORAGE permission

I realize even I do not have
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
in my `AndroidManifest.xml
String path = Images.Media.insertImage(((Activity)MainView.this.getContext()).getContentResolver(), screenCaptureBitmap, "Title", "Description");
still able to write image file to location /mnt/sdcard/DCIM/Camera. May I know why is it so?

maybe in depend on the content provider MediaStore, you through it to insert, it's a RPC invoke. and the MediaStore provider in source code: packages/providers/MediaProvider, in it's manifest define the permission
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />,
may be it's the reason.