检查是否授予通知权限（Xamarin，iOS）

Question

The user is prompted to deny/grant permission for notifications:

screenshot

The app has a settings view where the user can toggle notifications. If the permission is not granted I want to point the user to the iOS settings (like WhatsApp does).

How do I check if the permissions got granted? Particularly in the case when a user grants permission but then decides to disable them from the iOS settings, not inside the app.

There is a wildly popular permissions plugin which sadly does not support this particular permission.

Answer 1

You can use DependencyService to check if notifications is enabled for the app.

In iOS:

[assembly: Dependency(typeof(DeviceService))]
  class DeviceService : IDeviceService
  {
    public bool GetApplicationNotificationSettings()
     {
     var settings = UIApplication.SharedApplication.CurrentUserNotificationSettings.Types;
            return settings != UIUserNotificationType.None;
     }
   } 

In Forms:

public interface IDeviceService
{
   bool GetApplicationNotificationSettings();
}

And after these, you can call your DependencyService from your page or view model like this:

bool isNotificationEnabled = DependencyService.Get<IDeviceService>().GetApplicationNotificationSettings();

Answer 2

Basically you need to request authorization on each app run. Therefore you'll know the authorization status and navigate users to ios settings of your app if you need to do so.

UNUserNotificationCenter.Current.RequestAuthorization(UNAuthorizationOptions.Alert | UNAuthorizationOptions.Badge | UNAuthorizationOptions.Sound, (approved, error) =>
            {
                // do something with approved
                // approved will be true if user given permission or false if not
            });

If the permission is given this method will return true on each run.. If it changes it will return false.

Answer 3

try this:

Device.OpenUri(new Uri("app-settings:"));

or you can do it like this (for android and iOS): https://dotnetco.de/open-app-settings-in-xamarin-forms/