Navigating to a Specific Page in .NET MAUI Blazor Using Shiny.Push Notifications

[Rebrandsoft]

Hi, first I want to thank you for the great work that has been done on this library. Saved me a lot of hassle and time.
I am currently developing a .NET MAUI Blazor application and using the Shiny.Push library to handle push notifications. I want to navigate the user to a specific page when they click on a push notification. However, I encountered an issue with the NavigationManager, as it does not seem to work outside of Blazor pages and components.

Setup

Push Delegate Implementation:

using Microsoft.AspNetCore.Components;
using Shiny.Push;
#if IOS
using UIKit;
using UserNotifications;
#endif

namespace App_v2.Delegates
{
    public partial class MyPushDelegate : IPushDelegate
    {
        private readonly NavigationManager _navigationManager;

        public MyPushDelegate(NavigationManager navigationManager)
        {
            _navigationManager = navigationManager;
        }

        public async Task OnEntry(PushNotification notification)
        {
            // Retrieve data from the notification
            if (notification.Data.TryGetValue("app_url", out var page))
            {
                var id = notification.Data.TryGetValue("id", out string? value) ? value.ToString() : null;
                _navigationManager.NavigateTo(id == null ? $"/{page}" : $"/{page}/{id}");
            }

            await Task.CompletedTask;
        }

        public async Task OnNewToken(string token)
        {
            await Task.CompletedTask;
        }

        public async Task OnReceived(PushNotification notification)
        {
            await Task.CompletedTask;
        }

        public async Task OnUnRegistered(string token)
        {
            await Task.CompletedTask;
        }
    }

#if IOS
    public partial class MyPushDelegate : Shiny.Push.IApplePushDelegate
    {
        // this is only used in a foreground call
        public UNNotificationPresentationOptions? GetPresentationOptions(PushNotification notification)
        {
#pragma warning disable CA1422 // Validate platform compatibility
            return UNNotificationPresentationOptions.Alert;
#pragma warning restore CA1422 // Validate platform compatibility
        }

        // this is executed on any content-available push notification
        public UIBackgroundFetchResult? GetFetchResult(PushNotification notification)
        {
            return UIBackgroundFetchResult.NewData;
        }
    }
#endif
}

Main Page Code:

MainPage.xaml.cs

using App_v2.Services.States;

namespace App_v2;

public partial class MainPage : ContentPage
{
    private readonly RefreshViewState _refreshViewState;

    public MainPage(RefreshViewState refreshViewState)
    {
        InitializeComponent();
        BindingContext = refreshViewState;
        _refreshViewState = refreshViewState;
    }

    private void RefreshView_Refreshing(object sender, EventArgs e)
    {
        _refreshViewState.SetIsRefreshing(true);
    }
}

MainPage.xaml:

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:App_v2"
             x:Class="App_v2.MainPage"
             xmlns:states="clr-namespace:App_v2.Services.States"
             BackgroundColor="{DynamicResource PageBackgroundColor}"
             x:DataType="states:RefreshViewState"
             xmlns:ios="clr-namespace:Microsoft.Maui.Controls.PlatformConfiguration.iOSSpecific;assembly=Microsoft.Maui.Controls"
             ios:Page.UseSafeArea="True">

    <OnPlatform x:TypeArguments="View">
        <On Platform="Android, iOS">
            <!--<RefreshView IsRefreshing="{Binding IsRefreshing}"
                 IsEnabled="{Binding IsEnabled}"
                 Refreshing="RefreshView_Refreshing">-->
                <BlazorWebView HostPage="wwwroot/index.html" x:Name="blazorWebView">
                    <BlazorWebView.RootComponents>
                        <RootComponent Selector="#app" ComponentType="{x:Type local:Main}" />
                    </BlazorWebView.RootComponents>
                </BlazorWebView>
            <!--</RefreshView>-->
        </On>
        <On Platform="WinUI">
            <BlazorWebView HostPage="wwwroot/index.html" x:Name="blazorWebViewWindows">
                <BlazorWebView.RootComponents>
                    <RootComponent Selector="#app" ComponentType="{x:Type local:Main}" />
                </BlazorWebView.RootComponents>
            </BlazorWebView>
        </On>
    </OnPlatform>

</ContentPage>

Problem

The NavigationManager does not work outside of Blazor components. This limitation is affecting my push notification handling in MyPushDelegate, preventing navigation to the desired Blazor page upon receiving and interacting with a notification.

Additionally, I've set LaunchMode = LaunchMode.SingleTop in my Android MainActivity to address an issue where the app sometimes gets stuck on the splash screen after clicking a push notification.

Environment Details

• Visual Studio: Microsoft Visual Studio Community 2022, Version 17.11.0 Preview 6.0
• .NET Version: .NET 8 (latest available build version)
• Shiny Library Setup Instructions: Shiny.Push Setup

Questions

Navigating from Push Notifications:

What is the best approach to navigate to a specific Blazor page upon receiving a push notification in a .NET MAUI Blazor app?
Should I consider using deep linking or another method to achieve this functionality?

Handling Badge Numbers:

How can I control and increment badge numbers in the OnReceived method?
Does this require platform-specific code, and if so, can you provide guidance or resources on how to implement it?
Integration with Firebase Crashlytics:

Will there be any conflicts using Shiny.Push and Shiny.Push.FirebaseMessaging alongside Plugin.Firebase.Crashlytics?
If conflicts exist, are there alternative methods for implementing Firebase Crashlytics in my application?
References

• Shiny.Push Documentation
• PushTester Example
• Plugin.Firebase.Crashlytics

Additional Information
Below are the implementations of AppDelegate.cs and MainActivity.cs for iOS and Android platforms respectively:

AppDelegate.cs

using Foundation;
using UIKit;
using App_v2.Interfaces;

namespace App_v2;

[Register("AppDelegate")]
public class AppDelegate : MauiUIApplicationDelegate
{
    protected override MauiApp CreateMauiApp()
        => MauiProgram.CreateMauiApp();

    [Export("application:didRegisterForRemoteNotificationsWithDeviceToken:")]
    public void RegisteredForRemoteNotifications(UIApplication application, NSData deviceToken)
          => global::Shiny.Hosting.Host.Lifecycle.OnRegisteredForRemoteNotifications(deviceToken);

    [Export("application:didFailToRegisterForRemoteNotificationsWithError:")]
    public void FailedToRegisterForRemoteNotifications(UIApplication application, NSError error)
        => global::Shiny.Hosting.Host.Lifecycle.OnFailedToRegisterForRemoteNotifications(error);

    [Export("application:didReceiveRemoteNotification:fetchCompletionHandler:")]
    public void DidReceiveRemoteNotification(UIApplication application, NSDictionary userInfo, Action<UIBackgroundFetchResult> completionHandler)
        => global::Shiny.Hosting.Host.Lifecycle.OnDidReceiveRemoteNotification(userInfo, completionHandler);
}

public class UrlLauncher : IURLLauncher
{
    public void OpenUrl(string url)
    {
        _ = UIApplication.SharedApplication.OpenUrl(new NSUrl(url));
    }
}

MainActivity.cs

using Android.App;
using Android.Content;
using Android.Content.PM;
using Android.OS;
using App_v2.Interfaces;
using App_v2.Platforms.Android;
using Shiny;
using Shiny.Push;
using Application = Android.App.Application;

namespace App_v2;

[Activity(
    LaunchMode = LaunchMode.SingleTop,
    Theme = "@style/Maui.SplashTheme",
    MainLauncher = true,
    ConfigurationChanges = ConfigChanges.ScreenSize |
    ConfigChanges.Orientation |
    ConfigChanges.UiMode |
    ConfigChanges.ScreenLayout |
    ConfigChanges.SmallestScreenSize |
    ConfigChanges.Density)]

[IntentFilter(
    new[] {
        ShinyPushIntents.NotificationClickAction
    },
    Categories = new[] {
        global::Android.Content.Intent.CategoryDefault
    }
)]

public class MainActivity : MauiAppCompatActivity
{

    protected override void OnCreate(Bundle? savedInstanceState)
    {
        base.OnCreate(savedInstanceState);
        WebViewSoftInputPatch.Initialize();
    }
}


public class UrlLauncher : IURLLauncher
{
    public void OpenUrl(string url)
    {
        var uri = Android.Net.Uri.Parse(url);
        var intent = new Intent(Intent.ActionView, uri);
        intent.AddFlags(ActivityFlags.NewTask);
        Application.Context.StartActivity(intent);
    }
}

[aritchie]

Navigating from Push Notifications

I stay out of this because everyone has different requirements. The navigation manager from blazor is not going to work inside of a push delegate though... of that much I'm sure

How can I control and increment badge numbers in the OnReceived method

This has to be part of the payload on iOS. On Android, there are hacks for badge icons

Will there be any conflicts using Shiny.Push and Shiny.Push.FirebaseMessaging alongside [Plugin.Firebase.Crashlytics]
(https://www.nuget.org/packages/Plugin.Firebase.Crashlytics/#readme-body-tab)

Likely - yes.

If conflicts exist, are there alternative methods for implementing Firebase Crashlytics in my application?

Use Sentry