Develop Reference

How to migrate an app in flutter from android 12 to android 13?

I need to migrate my application from android 12 to android 13 since in android 12 it does not show any errors, however when testing the app on a device with android 13 it gives me the following error:
[MethodChannelFilePicker] Platform exception:
PlatformException(read_external_storage_denied, User did not allow
reading external storage, null, null).
I've tried adding validations in the manifest, like the ones in:
I have also tried adding these validations in the main:

Add the following permission in your manifest.xml inside
<uses-permission android:name="android.permission.MEDIA_CONTENT_CONTROL"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
If it still does not work out, upgrade or change the package you use for picking files and check the documentation.
recommended : https://pub.dev/packages/file_picker/versions/5.2.5

Access Download folder on Android 10

I have a working code that exports some files in the Downloads folder. I'm using requestLegacyExternalStorage to be able to access the folder on Android 10-. Everything works.
Since Google Play Store requested to remove the flag
requestLegacyExternalStorage="true"
I have tried to remove it. I don't need to migrate anything so it has been relatively simple and it works fine on Android 9- and Android 11. On Android 10 it does not work. The app crashes with
android.system.ErrnoException: open failed: EACCES (Permission denied)
In the AndroidManifest I have:
<uses-permission
android:name="android.permission.READ_EXTERNAL_STORAGE"
android:maxSdkVersion="29"/>
<uses-permission
android:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="29" />
I have granted permission to access the external store.
The crash happens when I call:
destination.outputStream()
where destination is a file in the Downloads folder.
What should I do? Why doesn't this work on Android 10 only?

The issue on Android 10, because you set in In the AndroidManifest : android:maxSdkVersion="29".
Android 10 is API level 29.
add in AndroidMainfest
in application node
android:requestLegacyExternalStorage="true"

How to fix 'EACCES (Permission denied)' error in android?

I am trying to delete a file on an external SD storage in android by using the following code:
filename = "/storage/extSdCard/AAA/testtitle.mp3"
File file = new File(filename)
file.delete()
I am also using the two permissions
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
in the Manifest (outside the application declaration), and I am using the code suggested here. The device does not seem to be a Marshmellow device (first answer), and the suggested solution in the third answer also does not help. I still get the same error:
remove failed: EACCES (Permission denied) : /storage/extSdCard/AAA/testtitle.mp3
What else can I try?

ACCESS_WIFI_STATE error on emulator

I've declared the following permission on the manifest:
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
And per the docs it's a normal permission so no need to request it at runtime on devices running Android M or higher.
The app has crashed but I've tested on multiple devices (with android N) and the app works has expected. Any idea why it has crashed on an emulator with Android SDK built for x86 running android 7.0?
Here is the stacktrace:
Fatal Exception: java.lang.SecurityException: WifiService: Neither user 10076 nor current process has android.permission.ACCESS_WIFI_STATE.
at android.os.Parcel.readException(Parcel.java:1683)
at android.os.Parcel.readException(Parcel.java:1636)
at android.net.wifi.IWifiManager$Stub$Proxy.getWifiEnabledState(IWifiManager.java:1198)
at android.net.wifi.WifiManager.getWifiState(WifiManager.java:1455)
at android.net.wifi.WifiManager.isWifiEnabled(WifiManager.java:1467)
...

To work with WifiManager when scanning the Connections from Android 6.0 it needs to access your location, so that is either the fine location or the coarse location, Add the following to Manifes.xml:
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

Since Android M (6+) you have to ask the user for permissions during runtime, like iOS-applications for instance.
You can read the docs here, a quick solution is to use a library, e.g EasyPermission or EasyPermission
https://github.com/jineshfrancs/EasyPermission
https://github.com/lalosoft/EasyPermissions
Usage:
easyPermission.requestPermission(this, Manifest.permission.ACCESS_WIFI_STATE);

Android 5(HTC) EACCES (Permission denied)

app can't create folder/file on android 5(HTC HTC6525LVW os version: 5.0.1) external storage in directory owned by app.
Parent folder is returned by [getExternalFilesDirs(String type)][1] method.
Sdcard is mounted.
Anyone else having this problem or suggestion how to solve it?
(Unfortunately I don't have this device to test it more)
Edit: From one user I know that prior this bug she encrypted sdcard and then formatted it.

Some potential ideas as to what caused it:
If the phone is running in USB Storage mode when connected to your computer you can still deploy/debug like normal but write operations will fail
You were missing a permission: in your manifest file you should check to see if you have <permission name=”android.permission.WRITE_EXTERNAL_STORAGE” >
Permissions in the wrong location: make sure that your permission tag (in manifest) is located outside of the application
Writing to the data folder can cause issues like this so make sure you're writing to sdcard and not data
This is everything I could think of. Hope it helps :)

Add permission to your manifest.xml file permissions
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />