Fix URL navigation from docs

Author: Sergio0694

samples/MvvmSample.Core/ViewModels/SamplePageViewModel.cs

@@ -68,9 +68,8 @@ private async Task LoadDocsAsync(string? name)
         using StreamReader reader = new(stream);
         string text = await reader.ReadToEndAsync();
 
-        // Fixups
-        string trimmedText = Regex.Replace(text, @"[ \r\n]+?!\[[^]]+\]\([^)]+\)[ \r\n]+?", string.Empty); // Drop image links
-        string updatedText = trimmedText.Replace("(/dotnet", "(https://docs.microsoft.com/dotnet"); // Update relative links
+        // Drop image links
+        string trimmedText = Regex.Replace(text, @"[ \r\n]+?!\[[^]]+\]\([^)]+\)[ \r\n]+?", string.Empty);
 
         Texts = MarkdownHelper.GetParagraphs(trimmedText);
 

samples/MvvmSampleUwp/Controls/DocumentationBlock.cs

@@ -2,6 +2,9 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+using Microsoft.Toolkit.Uwp.UI.Controls;
+using Windows.System;
 using Windows.UI.Xaml;
 using Windows.UI.Xaml.Controls;
 
@@ -10,8 +13,39 @@ namespace MvvmSampleUwp.Controls;
 /// <summary>
 /// A simple control that acts as a container for a documentation block.
 /// </summary>
+[TemplatePart(Name = "PART_MarkdownTextBlock", Type = typeof(MarkdownTextBlock))]
 public sealed class DocumentationBlock : ContentControl
 {
+    /// <summary>
+    /// The <see cref="MarkdownTextBlock"/> instance in use.
+    /// </summary>
+    private MarkdownTextBlock markdownTextBlock;
+
+    /// <inheritdoc/>
+    protected override void OnApplyTemplate()
+    {
+        base.OnApplyTemplate();
+
+        markdownTextBlock = (MarkdownTextBlock)GetTemplateChild("PART_MarkdownTextBlock");
+
+        markdownTextBlock.LinkClicked += MarkdownTextBlock_LinkClicked;
+    }
+
+    /// <summary>
+    /// Handles a clicked link in a markdown block.
+    /// </summary>
+    /// <param name="sender">The source <see cref="MarkdownTextBlock"/> control.</param>
+    /// <param name="e">The input arguments.</param>
+    private void MarkdownTextBlock_LinkClicked(object sender, LinkClickedEventArgs e)
+    {
+        if (Uri.TryCreate(e.Link, UriKind.Absolute, out Uri result) ||
+            (e.Link.StartsWith("/dotnet") &&
+             Uri.TryCreate($"https://docs.microsoft.com{e.Link}", UriKind.Absolute, out result)))
+        {
+            _ = Launcher.LaunchUriAsync(result);
+        }
+    }
+
     /// <summary>
     /// Gets or sets the <see cref="string"/> representing the text to display.
     /// </summary>

samples/MvvmSampleUwp/Controls/DocumentationBlock.xaml

@@ -21,6 +21,7 @@
                         BorderThickness="1"
                         CornerRadius="4">
                         <controls:MarkdownTextBlock
+                            Name="PART_MarkdownTextBlock"
                             Padding="12"
                             Background="Transparent"
                             BorderBrush="Transparent"