using System; using Windows.Foundation; using Windows.Graphics.Display; using Windows.UI.Xaml; using Windows.UI.Xaml.Controls; using Windows.UI.Xaml.Media; using Xamarin.Forms.Controls; using Xamarin.Forms.Platform.WinRT; namespace Xamarin.Forms.ControlGallery.Windows { public sealed partial class MainPage { public MainPage () { InitializeComponent (); var app = new Controls.App (); // When the native control gallery loads up, it'll let us know so we can add the nested native controls MessagingCenter.Subscribe(this, NestedNativeControlGalleryPage.ReadyForNativeControlsMessage, AddNativeControls); LoadApplication (app); } static void AddNativeControls (NestedNativeControlGalleryPage page) { if (page.NativeControlsAdded) { return; } StackLayout sl = page.Layout; // Create and add a native TextBlock var originalText = "I am a native TextBlock"; var textBlock = new TextBlock { Text = originalText, FontSize = 14, FontFamily = new FontFamily ("HelveticaNeue") }; sl?.Children.Add (textBlock); // Create and add a native Button var button = new global::Windows.UI.Xaml.Controls.Button { Content = "Click to toggle font size", Height = 80 }; button.Click += (sender, args) => { textBlock.FontSize = textBlock.FontSize == 14 ? 24 : 14; }; sl?.Children.Add (button.ToView ()); // Create a control which we know doesn't behave correctly with regard to measurement var difficultControl = new BrokenNativeControl { Text = "Not Sized/Arranged Properly" }; var difficultControl2 = new BrokenNativeControl { Text = "Fixed" }; // Add the misbehaving controls, one with a custom delegate for ArrangeOverrideDelegate sl?.Children.Add (difficultControl); sl?.Children.Add (difficultControl2, arrangeOverrideDelegate: (renderer, finalSize) => { if (finalSize.Width <= 0 || double.IsInfinity (finalSize.Width)) { return null; } FrameworkElement frameworkElement = renderer.Control; frameworkElement.Measure (finalSize); // The broken control tries sizes itself to be the width of the screen var wrongSize = Window.Current.Bounds.Width * (int)DisplayProperties.ResolutionScale / 100; // We can re-center it by offsetting it during the Arrange call double diff = Math.Abs(finalSize.Width - wrongSize) / -2; frameworkElement.Arrange (new Rect (diff, 0, finalSize.Width - diff, finalSize.Height)); // Arranging the control to the left will make it show up past the edge of the stack layout // We can fix that by clipping it manually var clip = new RectangleGeometry { Rect = new Rect (-diff, 0, finalSize.Width, finalSize.Height) }; frameworkElement.Clip = clip; return finalSize; } ); page.NativeControlsAdded = true; } } }