Run OnParameterSet when navigating even if there are no parameters set, to align how it works in Blazor

Author: dhindrik

src/TinyMvvm.Maui/TinyNavigation.cs

@@ -1,4 +1,5 @@
 using System.Collections;
+using System.Reflection.Metadata;
 
 namespace TinyMvvm;
 
@@ -14,7 +15,12 @@ public TinyNavigation()
     /// <inheritdoc />
     public async Task NavigateTo(string key)
     {
-        await Shell.Current.GoToAsync(key);
+        var parameters = new Dictionary<string, object>
+        {
+            { "tinyEmpty", string.Empty }
+        };
+
+        await Shell.Current.GoToAsync(key, parameters);
 
     }
 
@@ -27,8 +33,10 @@ public async Task NavigateTo(string key, object parameter)
             return;
         }
 
-        var parameters = new Dictionary<string, object>();
-        parameters.Add("tinyParameter", parameter);
+        var parameters = new Dictionary<string, object>
+        {
+            { "tinyParameter", parameter }
+        };
 
         await Shell.Current.GoToAsync(key, parameters);
     }

src/TinyMvvm.Maui/TinyViewModel.cs

@@ -115,6 +115,7 @@ public bool IsNotInitialized
     }
 
     private const string TinyParameterKey = "tinyParameter";
+    private const string TinyEmptyKey = "tinyEmpty";
     /// <inheritdoc />
     public async void ApplyQueryAttributes(IDictionary<string, object> query)
     {
@@ -123,6 +124,12 @@ public async void ApplyQueryAttributes(IDictionary<string, object> query)
             return;
         }
 
+        if(query.ContainsKey(TinyEmptyKey))
+        {
+            await RunOnParameterSet();
+            return;
+        }
+
         if (query.ContainsKey(TinyParameterKey))
         {
             NavigationParameter = query[TinyParameterKey];
@@ -149,6 +156,11 @@ public async void ApplyQueryAttributes(IDictionary<string, object> query)
             QueryParameters = query;
         }
 
+        await RunOnParameterSet();
+    }
+
+    private async Task RunOnParameterSet()
+    {
         if (TinyDispatcher.IsMainThread)
         {
             await OnParameterSet();

src/TinyMvvm.Sample/MauiProgram.cs

@@ -35,6 +35,7 @@ public static MauiApp CreateMauiApp()
         builder.Services.AddTransient<DetailsViewModel>();
 
 		Routing.RegisterRoute(nameof(DetailsViewModel), typeof(DetailsView));
+        Routing.RegisterRoute(nameof(ListViewModel), typeof(ListView));
 
         return builder.Build();
 	}

src/TinyMvvm.Sample/ViewModels/ListViewModel.cs

@@ -26,6 +26,11 @@ public override async Task Initialize()
             IsBusy = false;
         }
 
+        public override async Task OnParameterSet()
+        {
+            await base.OnParameterSet();
+        }
+
         [ObservableProperty]
         private ObservableCollection<City> cities = new ObservableCollection<City>();
 

src/TinyMvvm.Sample/ViewModels/MainViewModel.cs

@@ -34,6 +34,16 @@ public MainViewModel(ICityService cityService)
         IsBusy = false;
     });
 
+    private ICommand showList;
+    public ICommand ShowList => showList ??= new RelayCommand(async () =>
+    {
+        IsBusy = true;
+
+        await Navigation.NavigateTo(nameof(ListViewModel));
+
+        IsBusy = false;
+    });
+
     private ICommand show;
     public ICommand Show => show ??= new RelayCommand<City>(async (city) =>
     {

src/TinyMvvm.Sample/Views/MainView.xaml

@@ -8,6 +8,7 @@
         <VerticalStackLayout Spacing="10">
             <Entry Text="{Binding Text}" Placeholder="Search city" />
             <Button Command="{Binding Search}" Text="Search" />
+            <Button Command="{Binding ShowList}" Text="ShowList" />
         </VerticalStackLayout>
         <ActivityIndicator Grid.Row="1" HorizontalOptions="Center" VerticalOptions="Center" IsRunning="{Binding IsBusy}" IsVisible="{Binding IsBusy}" />
         <CollectionView Grid.Row="1" x:Name="CityList" ItemsSource="{Binding Cities}" IsVisible="{Binding IsNotBusy}">