How do I handle deep linking for push notifications in MvvmCross

1. Setting Up Deep Linking**

First, you need to set up deep linking in your app. This typically involves configuring your app's manifest or plist to handle specific URLs. For Android, you add intent filters to your activities in the `AndroidManifest.xml`, while for iOS, you configure URL schemes in the app's plist file.

2. Using MvvmCross Routing Plugin**

The MvvmCross Routing Plugin is a powerful tool for deep linking. It allows you to define routes using URL-based navigation. Here's how you can use it:

- Define Routes: Use assembly attributes to define routes for your view models. For example, you can use a regex pattern to capture parameters from the URL:

csharp
  [assembly: MvxRouting(typeof(ViewModelA), @"mvx://test/\?id=(?[A-Z0-9]{32})$")]
  

- Implement Routing Service: The routing service is registered as a singleton and uses `IMvxViewDispatcher` to show view models. You can inject this service into your view models to navigate using URLs:

csharp
  public class MainViewModel : MvxViewModel
  {
      private readonly IMvxRoutingService _routingService;

      public MainViewModel(IMvxRoutingService routingService)
      {
          _routingService = routingService;
      }

      public ICommand ShowACommand => new MvxAsyncCommand(async () =>
      {
          await _routingService.RouteAsync("mvx://test/?id=" + Guid.NewGuid().ToString("N"));
      });
  }
  

3. Handling Push Notifications**

When handling push notifications, you need to include the deep link in the notification payload. For example, if you're using Azure Notification Hubs, you can include a URL in the `aps` object for iOS notifications:

json
"aps": {
    "alert": {
        "title": "xxxx",
        "body": "xxxx"
    },
    "url": "mvx://test/?id=yourid"
}

For Android, you can pass custom data in the notification payload and handle it in your app.

4. Navigating from Notifications**

When the app is not running and a notification is clicked, the app will launch. You can then use the MvvmCross routing service to navigate to the correct view model based on the URL or parameters passed in the notification.

If MvvmCross hasn't initialized when the app starts from a notification, you might need to save the notification data and navigate once the app is fully initialized. Here’s a basic approach:

1. Save Notification Data: When the app starts from a notification, save the notification data (e.g., the URL or parameters) in app preferences or a similar storage mechanism.

2. Check for Saved Data: In your main activity or startup logic, check if there is saved notification data. If there is, use the MvvmCross routing service to navigate to the appropriate view model.

5. Handling Non-UI Initialization**

If you need to initialize MvvmCross components outside of the UI (e.g., in a broadcast receiver), you can manually initialize the MvvmCross setup. However, this is typically not necessary for handling push notifications, as the app will launch and initialize MvvmCross when a notification is clicked.

Conclusion

Deep linking in MvvmCross for push notifications involves setting up URL-based routing, including deep links in notification payloads, and navigating to the correct view models when the app launches from a notification. By leveraging the MvvmCross Routing Plugin and handling notification data appropriately, you can provide a seamless user experience by directing users to specific in-app screens from push notifications.