refacto API prefix + nav.back

src/PostIt/PostIt/App.axaml.cs

@@ -350,4 +350,9 @@ public partial class App : Application
 
         return window.NavRoot.PushAsync(page);
     }
+
+    internal async Task GoBackAsync()
+    {
+        await window.NavRoot.PopAsync();
+    }
 }

src/PostIt/PostIt/ViewModels/AddCircleMemberDialogViewModel.cs

@@ -5,6 +5,7 @@ using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using PostIt.Services;
+using PostIt.Views;
 using Yavsc.Api.Client;
 
 namespace PostIt.ViewModels;
@@ -106,7 +107,7 @@ public partial class AddCircleMemberDialogViewModel : ViewModelBase
     /// UI from firing an event with a null payload.
     /// </summary>
     [RelayCommand]
-    public void Add()
+    public async Task AddAsync()
     {
         if (Selected is null)
         {
@@ -114,5 +115,14 @@ public partial class AddCircleMemberDialogViewModel : ViewModelBase
             return;
         }
         Confirmed?.Invoke(this, Selected);
+        var app = App.Current as App;
+        await app.GoBackAsync();
+    }
+
+    [RelayCommand]
+    public async Task CloseAsync()
+    {
+        var app = App.Current as App;
+        await app.GoBackAsync();
     }
 }

src/PostIt/PostIt/ViewModels/CirclesPageViewModel.cs

@@ -119,6 +119,17 @@ public partial class CirclesPageViewModel : ViewModelBase
         var directory = services.GetRequiredService<IUserDirectory>();
         AddCircleMemberDialogViewModel model =
         new AddCircleMemberDialogViewModel(directory);
+        // Wire the dialog's Confirmed event to OnAddMemberConfirmedAsync.
+        // Without this, the dialog's "Ajouter" button fires the event
+        // into the void: no subscriber, the picked user is silently
+        // dropped, and nothing is added to the circle. The dialog
+        // stays open until the user uses the back gesture — which is
+        // how the user noticed the button was a no-op.
+        // Async-void is intentional here: Confirmed is an
+        // EventHandler<T> (returns void), and bridging to the
+        // async Task OnAddMemberConfirmedAsync requires it.
+        model.Confirmed += async (_, picked) =>
+            await OnAddMemberConfirmedAsync(_, picked);
         await app.PushPageAsync(model);
     }
     /// <summary>

src/PostIt/PostIt/ViewModels/PostAclDialogViewModel.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
-using System.Linq;
 using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
@@ -52,6 +51,22 @@ public partial class PostAclDialogViewModel : ViewModelBase
     [ObservableProperty]
     public partial string StatusMessage { get; set; } = string.Empty;
 
+    /// <summary>
+    /// Idempotency gate for <see cref="LoadAsync"/>: the dialog
+    /// attaches the load trigger in <c>DataContextChanged</c>,
+    /// which can fire more than once if the page is detached
+    /// and re-attached (dialog re-use, navigation edge cases)
+    /// with a different VM. Without this guard, the second load
+    /// would race against the first and could overwrite
+    /// <see cref="AclEntries"/> mid-edit. Pattern copied from
+    /// <c>Settings.Load</c>.
+    /// </summary>
+    private bool _loaded;
+
+    /// <summary>True once <see cref="LoadAsync"/> has run at least
+    /// once. Exposed for tests; do not bind from XAML.</summary>
+    public bool Loaded => _loaded;
+
     public PostAclDialogViewModel(
         BlogPostDto post,
         BlogAclApiClient aclClient,
@@ -68,6 +83,8 @@ public partial class PostAclDialogViewModel : ViewModelBase
     [RelayCommand]
     public async Task LoadAsync()
     {
+        if (_loaded) return;
+
         IsBusy = true;
         try
         {
@@ -83,6 +100,7 @@ public partial class PostAclDialogViewModel : ViewModelBase
 
 
             StatusMessage = $"{AclEntries.Count} autorisation(s)";
+            _loaded = true;
         }
         catch (Exception ex)
         {

src/PostIt/PostIt/Views/AddCircleMemberDialog.axaml

@@ -6,6 +6,7 @@
         xmlns:services="using:PostIt.Services"
         x:DataType="vm:AddCircleMemberDialogViewModel"
       >
+
     <Grid RowDefinitions="Auto,Auto,*,Auto" Margin="12">
 
         <!-- Search box + button -->
@@ -29,7 +30,9 @@
         <!-- Search results -->
         <ListBox Grid.Row="2"
                  ItemsSource="{Binding Results}"
-                 SelectedItem="{Binding Selected, Mode=TwoWay}">
+                 SelectedItem="{Binding Selected, Mode=TwoWay}"
+                MinHeight="20"
+                 >
             <ListBox.ItemTemplate>
                 <DataTemplate x:DataType="services:UserSummary">
                     <StackPanel Spacing="2">
@@ -47,11 +50,13 @@
             <TextBlock Grid.Column="0" Text="{Binding StatusMessage}"
                        VerticalAlignment="Center"/>
             <Button Grid.Column="1" Content="Ajouter"
-                    Command="{Binding Add}"
+                    x:Name="AddButton"
+                    Command="{Binding AddAsync}"
                     IsEnabled="{Binding Selected, Converter={x:Static ObjectConverters.IsNotNull}}"
                     Margin="0,0,8,0"/>
             <Button Grid.Column="2" Content="Fermer"
-                    Click="OnCloseClicked"/>
+                    x:Name="CloseButton"
+                   Command="{Binding CloseAsync}"/>
         </Grid>
     </Grid>
 </ContentPage>

src/PostIt/PostIt/Views/AddCircleMemberDialog.axaml.cs

@@ -1,6 +1,7 @@
 using Avalonia.Controls;
 using Avalonia.Markup.Xaml;
 using Avalonia.Interactivity;
+using Avalonia.VisualTree;
 using PostIt.Services;
 using PostIt.ViewModels;
 
@@ -41,8 +42,8 @@ public partial class AddCircleMemberDialog : ContentPage
 
     private void OnCloseClicked(object? sender, RoutedEventArgs e)
     {
-        // Same light-modal pattern as PostAclDialog: rely on
-        // the system back gesture or the navigation host's
-        // "pop" — the ContentPage doesn't own the back stack.
+        var nav = this.FindAncestorOfType<NavigationPage>();
+        if (nav is not null)
+            _ = nav.PopAsync();
     }
 }

src/PostIt/PostIt/Views/PostAclDialog.axaml.cs

@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Controls;
 using Avalonia.Markup.Xaml;
 using PostIt.ViewModels;
@@ -9,21 +10,53 @@ namespace PostIt.Views;
 /// <summary>
 /// Modal "manage ACL" page for a single blog post.
 ///
-/// <para>The ViewModel is constructed here (not via DI) because it
-/// depends on the post being managed, which the caller (the post
-/// list page) only knows at the moment it opens the dialog. The
-/// DI container can build the two API clients; the post and the
-/// VM are wired together here.</para>
+/// <para>The ViewModel is constructed by the caller (the post
+/// list page) and handed to <see cref="App.PushPageAsync"/>,
+/// which routes through <see cref="ViewLocator"/> and lands
+/// here via the parameterless DI constructor. The VM is then
+/// assigned to <see cref="ContentPage.DataContext"/> by
+/// <c>App.PushPageAsync</c> — we listen for that one-shot
+/// assignment and trigger <c>LoadAsync</c> right after, so the
+/// dropdown's <c>MyCircles</c> and the list's <c>AclEntries</c>
+/// are populated when the dialog appears. The VM is idempotent
+/// under repeated loads.</para>
 /// </summary>
 public partial class PostAclDialog : ContentPage
 {
     public PostAclDialog()
     {
         InitializeComponent();
+
+        // App.PushPageAsync wires the VM via DataContext after
+        // building the page. We subscribe once to fire LoadAsync
+        // the moment the VM is attached. Using DataContextChanged
+        // (rather than AttachedToVisualTree) is what makes this
+        // work in the headless test harness too: the load is
+        // tied to the VM being available, not to the visual tree
+        // being realised (which is a separate concern).
+        EventHandler? handler = null;
+        handler = (_, _) =>
+        {
+            if (DataContext is PostAclDialogViewModel vm)
+            {
+                this.DataContextChanged -= handler;
+                _ = vm.LoadAsync();
+            }
+        };
+        this.DataContextChanged += handler;
     }
 
     public PostAclDialog(BlogPostDto post, BlogAclApiClient aclClient, CircleApiClient circleClient)
     {
+        // This overload is not used by the production path —
+        // MainPageViewModel pushes the VM via App.PushPageAsync
+        // and App routes through ViewLocator, which resolves this
+        // page via the parameterless ctor. It is kept so test
+        // scaffolding that wants to bypass the nav pipeline can
+        // still wire a VM directly without losing the load
+        // trigger: the constructor sets DataContext before the
+        // DataContextChanged subscription fires, so the load
+        // is guaranteed to run in either case.
         InitializeComponent();
         DataContext = new PostAclDialogViewModel(post, aclClient, circleClient);
     }