Using Manage_External_Storage with .net Maui

Question

So i am Creating an android app with .net Maui, that reads an XML file from my Documents(/storage/emulated/0/Documents) folder. The App is 100% capable of generating its own XML file to ensure that it always exists. However if i Replace the XML the Application crashes with an access denied execption. I believe this is due to the Fact that i am Using Storage_Read and Storage_Write Permissions instead of Manage_External_Storage. I am now Looking for a workaround to geting that permission since .net maui has not yet updated its permission system to API level 34.

The code That Requests Permissions:

PermissionStatus lReadStatus = await Permissions.RequestAsync<Permissions.StorageRead>();  
PermissionStatus lWriteStatus =await Permissions.RequestAsync<Permissions.StorageWrite>();

My Android Manifest.xml:

    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.MANAGE_DOCUMENTS" />
    <uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE" />

Answer 1

To check external storage permission, you can use native android code. Here is a simple example.

in Platforms -> Android add CheckPermissions.cs file

namespace CheckPermissionManager
{
    public static class CheckPermission
    {
        public static bool CheckExternalStoragePermission()
        {
            if (Build.VERSION.SdkInt >= BuildVersionCodes.R)
            {
                var result = Android.OS.Environment.IsExternalStorageManager;
                if (!result)
                {
                    var manage = Settings.ActionManageAppAllFilesAccessPermission;
                    Intent intent = new Intent(manage);
                    Android.Net.Uri uri = Android.Net.Uri.Parse("package:" + AppInfo.Current.PackageName);
                    intent.SetData(uri);
                    Platform.CurrentActivity.StartActivity(intent);
                }
                return result;
            }

            return true;
        }
    }
}

then anywhere in code:

public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();
    }

    private async void OnClicked(object sender, EventArgs e)
    {
#if ANDROID
        CheckPermissionManager.CheckPermission.CheckExternalStoragePermission();
#endif
    }
}

Permission can only be manually added from app setting page. Above code opens manage external permission page if these permissions are not added.

Changing it to service would probably be a good idea.