Add chapter 10 sample project

2026-06-20 12:23:09 +00:00 · 2023-08-13 13:40:04 -04:00
parent f9e4d407b9
commit 90f935f4b2
91 changed files with 4110 additions and 0 deletions
@@ -0,0 +1,122 @@
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using Microsoft.UI.Xaml.Navigation;
+using Microsoft.Xaml.Interactivity;
+
+using TemplateStudioSampleApp.Contracts.Services;
+
+namespace TemplateStudioSampleApp.Behaviors;
+
+public class NavigationViewHeaderBehavior : Behavior<NavigationView>
+{
+    private static NavigationViewHeaderBehavior? _current;
+
+    private Page? _currentPage;
+
+    public DataTemplate? DefaultHeaderTemplate
+    {
+        get; set;
+    }
+
+    public object DefaultHeader
+    {
+        get => GetValue(DefaultHeaderProperty);
+        set => SetValue(DefaultHeaderProperty, value);
+    }
+
+    public static readonly DependencyProperty DefaultHeaderProperty =
+        DependencyProperty.Register("DefaultHeader", typeof(object), typeof(NavigationViewHeaderBehavior), new PropertyMetadata(null, (d, e) => _current!.UpdateHeader()));
+
+    public static NavigationViewHeaderMode GetHeaderMode(Page item) => (NavigationViewHeaderMode)item.GetValue(HeaderModeProperty);
+
+    public static void SetHeaderMode(Page item, NavigationViewHeaderMode value) => item.SetValue(HeaderModeProperty, value);
+
+    public static readonly DependencyProperty HeaderModeProperty =
+        DependencyProperty.RegisterAttached("HeaderMode", typeof(bool), typeof(NavigationViewHeaderBehavior), new PropertyMetadata(NavigationViewHeaderMode.Always, (d, e) => _current!.UpdateHeader()));
+
+    public static object GetHeaderContext(Page item) => item.GetValue(HeaderContextProperty);
+
+    public static void SetHeaderContext(Page item, object value) => item.SetValue(HeaderContextProperty, value);
+
+    public static readonly DependencyProperty HeaderContextProperty =
+        DependencyProperty.RegisterAttached("HeaderContext", typeof(object), typeof(NavigationViewHeaderBehavior), new PropertyMetadata(null, (d, e) => _current!.UpdateHeader()));
+
+    public static DataTemplate GetHeaderTemplate(Page item) => (DataTemplate)item.GetValue(HeaderTemplateProperty);
+
+    public static void SetHeaderTemplate(Page item, DataTemplate value) => item.SetValue(HeaderTemplateProperty, value);
+
+    public static readonly DependencyProperty HeaderTemplateProperty =
+        DependencyProperty.RegisterAttached("HeaderTemplate", typeof(DataTemplate), typeof(NavigationViewHeaderBehavior), new PropertyMetadata(null, (d, e) => _current!.UpdateHeaderTemplate()));
+
+    protected override void OnAttached()
+    {
+        base.OnAttached();
+
+        var navigationService = App.GetService<INavigationService>();
+        navigationService.Navigated += OnNavigated;
+
+        _current = this;
+    }
+
+    protected override void OnDetaching()
+    {
+        base.OnDetaching();
+
+        var navigationService = App.GetService<INavigationService>();
+        navigationService.Navigated -= OnNavigated;
+    }
+
+    private void OnNavigated(object sender, NavigationEventArgs e)
+    {
+        if (sender is Frame frame && frame.Content is Page page)
+        {
+            _currentPage = page;
+
+            UpdateHeader();
+            UpdateHeaderTemplate();
+        }
+    }
+
+    private void UpdateHeader()
+    {
+        if (_currentPage != null)
+        {
+            var headerMode = GetHeaderMode(_currentPage);
+            if (headerMode == NavigationViewHeaderMode.Never)
+            {
+                AssociatedObject.Header = null;
+                AssociatedObject.AlwaysShowHeader = false;
+            }
+            else
+            {
+                var headerFromPage = GetHeaderContext(_currentPage);
+                if (headerFromPage != null)
+                {
+                    AssociatedObject.Header = headerFromPage;
+                }
+                else
+                {
+                    AssociatedObject.Header = DefaultHeader;
+                }
+
+                if (headerMode == NavigationViewHeaderMode.Always)
+                {
+                    AssociatedObject.AlwaysShowHeader = true;
+                }
+                else
+                {
+                    AssociatedObject.AlwaysShowHeader = false;
+                }
+            }
+        }
+    }
+
+    private void UpdateHeaderTemplate()
+    {
+        if (_currentPage != null)
+        {
+            var headerTemplate = GetHeaderTemplate(_currentPage);
+            AssociatedObject.HeaderTemplate = headerTemplate ?? DefaultHeaderTemplate;
+        }
+    }
+}
@@ -0,0 +1,8 @@
+namespace TemplateStudioSampleApp.Behaviors;
+
+public enum NavigationViewHeaderMode
+{
+    Always,
+    Never,
+    Minimal
+}