Xamarin.Forms-Android：永远不会调用OnRequestPermissionsResult

Question

在Android下，我需要一些权限才能使用Google-Map API。我使用PermissionsPlugin：

https://www.nuget.org/packages/Plugin.Permissions/

这里有一些代码：

async void RequestPermissions()
{
    var status = await CrossPermissions.Current.CheckPermissionStatusAsync(Permission.Location);
    if (status != PermissionStatus.Granted)
    {
        if (await CrossPermissions.Current.ShouldShowRequestPermissionRationaleAsync(Permission.Location))
        {
            //NavigationHelper.CurrentPage.DisplayAlert("Need location", "Gunna need that location", "OK");
        }

        var results = await CrossPermissions.Current.RequestPermissionsAsync(Permission.Location);

        //Best practice to always check that the key exists
        if (results.ContainsKey(Permission.Location))
            status = results[Permission.Location];
    }
}

public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)
{
    PermissionsImplementation.Current.OnRequestPermissionsResult(requestCode, permissions, grantResults);
    //base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
}

但是我还注意到，从未调用过“ OnRequestPermissionsResult”方法，并且没有对话框向我询问权限！

此外，权限也位于清单文件中！

有什么办法解决这个问题吗？