How to solve Flutter error while trying to write in a file: "OS Error: Operation not permitted, errno = 1"?

Question

I am trying to write in a .txt file in my flutter program. I am using Permission_handler package and when I run the code (using mi 10) the app ask for permission to access to media and file and I hit allow, and the Debug console says "I/flutter (15890): PermissionStatus.granted" (I mean i did all the part about updating the AndroidManifest.xml or modification on "gradle.properties" , etc.). But when it comes to writing in the file, it throws this error:

E/flutter (15890): [ERROR:flutter/lib/ui/ui_dart_state.cc(186)] Unhandled Exception: FileSystemException: Cannot open file, path = '/storage/emulated/0/Download/X.txt' (OS Error: Operation not permitted, errno = 1)

I really appreciate any thought on this.

Answer 1

Mi 10 runs on Android 10. You need to add the following attribute to the <application> element in the AndroidManifest.xml:

android:requestLegacyExternalStorage="true"

This opts you into the legacy storage model.

Also set targetSdkVersion to 29, and compileSdkVersion to 29 or 30 in build.gradle

Answer 2

I think this happening in Android 11 due to their new changes. So you have to add one more permission (manageExternalStorage).

Like this

if (Platform.isAndroid) {

  Map<Permission, PermissionStatus> statuses = await [
  Permission.manageExternalStorage
  ].request();//Permission.manageExternalStorage
}

Even you have to add read & write permission as well.