Merge pull request #127 from jinaga/unload-on-logout

Provide a way to unload view models on log out

Jinaga.Maui/Binding/INavigationLifecycleManager.cs

@@ -14,4 +14,9 @@ public interface INavigationLifecycleManager
     /// </summary>
     /// <param name="viewModel">The view model to stop managing</param>
     void Hidden(ILifecycleManaged viewModel);
+    /// <summary>
+    /// Unload all view models that are not visible.
+    /// Call this method when the user logs out.
+    /// </summary>
+    void UnloadInvisible();
 }

Jinaga.Maui/Binding/NavigationLifecycleManager.cs

@@ -37,6 +37,15 @@ public void Hidden(ILifecycleManaged viewModel)
         }
     }
 
+    public void UnloadInvisible()
+    {
+        foreach (var viewModel in loadedViewModels.Except(visibleViewModels))
+        {
+            viewModel.Unload();
+            loadedViewModels = loadedViewModels.Remove(viewModel);
+        }
+    }
+
     // Invariants:
     // All visible view models are loaded.
     // No descendants of a visible view model are loaded, unless