Using PageResolver to pass data in Shell.

[spuliy]

Hello, I was wondering if I could use this plugin to pass data instead of using query parameters in Shell navigation. For example:

Shell.Current.Navigation.PushAsync<MyPage>(new Item { Property = "Something" });

Navigating to Page:

      public MyPage(MyPageModel viewmodel, Item value)
	{
            InitializeComponent();
            
            BindingContext = viewmodel;
  
            
            viewmodel.Init(Item);
        }
    

I get an exception when I try this:

'A suitable constructor for type 'App.Pages.MyPage' could not be located. Ensure the type is concrete and all parameters of a public constructor are either registered as services or passed as arguments. Also ensure no extraneous arguments are provided.'

But I'm not sure if that is because I'm not allowed to do this if I am using Shell or I am doing something wrong. I saw a question similar to this but I was not sure if it meant this was allowed in Shell Navigation or not.

[IeuanWalker]

Have you registered MyPage and your ViewModel with the DI container?

[spuliy]

I believe so. This is a summarized format of what I have registered:

	public static MauiApp CreateMauiApp()
	{
	  var builder = MauiApp.CreateBuilder();
	  builder
		  .UseMauiApp<App>()
		  .RegisterPageModels()
		  .RegisterPages()
		  .UsePageResolver();

	  MauiApp mauiapp = builder.Build();

	  return mauiapp;
	}

	public static MauiAppBuilder RegisterPageModels(this MauiAppBuilder mauiAppBuilder)
	{
	  mauiAppBuilder.Services.AddTransient<MyPageModel>();
	  return mauiAppBuilder;
	}

	public static MauiAppBuilder RegisterPages(this MauiAppBuilder mauiAppBuilder)
	{
	  mauiAppBuilder.Services.AddTransient<MyPage>();

	  return mauiAppBuilder;
	}

[IeuanWalker]

@spuliy personally im not sure you need to use this package if your using shell, as it has dependency resolution built in (i dont use shell though, so cant really comment on this) - https://learn.microsoft.com/en-us/dotnet/maui/fundamentals/dependency-injection?view=net-maui-8.0#automatic-dependency-resolution

Does it work if you just use -

Navigation.PushAsync<MyPage>(new Item 
{ 
    Property = "Something"
 });

Instead of -

Shell.Current.Navigation.PushAsync<MyPage>(new Item 
{ 
    Property = "Something"
 });

[matt-goldman]

@spuliy personally im not sure you need to use this package if your using shell, as it has dependency resolution built in (i dont use shell though, so cant really comment on this) - https://learn.microsoft.com/en-us/dotnet/maui/fundamentals/dependency-injection?view=net-maui-8.0#automatic-dependency-resolution

Does it work if you just use -

Navigation.PushAsync<MyPage>(new Item 
{ 
    Property = "Something"
 });

Instead of -

Shell.Current.Navigation.PushAsync<MyPage>(new Item 
{ 
    Property = "Something"
 });

Agree here - using Shell.Current.Navigation.PushAsync doesn't really make sense. Shell is within the navigation stack (where you would use PushAsync), whereas navigation within Shell would typically use GoToAsync which, as @IeuanWalker points out, has dependency resolution already built in.

Additionally, if you're navigating with Shell, you would also typically use query parameters or navigation state to pass values. https://learn.microsoft.com/en-us/dotnet/maui/fundamentals/shell/navigation?view=net-maui-8.0#pass-data

Again as @IeuanWalker says I'm not sure this package is right for your use case, but if you can elaborate a bit more on what you're doing here happy to help out. One use case here might be if you're trying to push a modal page, that might make sense. Otherwise combining hierarchical navigation with Shell is probably just making problems for yourself.

[spuliy]

Thank you @IeuanWalker and @matt-goldman for the advice, you guys are correct. Shell did have mostly everything I needed.

The only problem I had was not being able to resolve a popup page using Mopups, but using the Mopups extension in this package I was able to resolve that issue. :)