Moved logic from MainWindow.axaml.cs to HeaderView.axaml.cs

XSDVisualiser.Desktop/MainWindow.axaml.cs

@@ -1,59 +1,12 @@
-using System;
-using System.Threading.Tasks;
 using Avalonia.Controls;
-using Avalonia.Interactivity;
-using Avalonia.Threading;
-using XSDVisualiser.Core;
-using XSDVisualiser.Models;
-using XSDVisualiser.Desktop.ViewModels;
-using XSDVisualiser.Desktop.Views;
 
 namespace XSDVisualiser.Desktop
 {
     public partial class MainWindow : Window
     {
-        private Button _openBtn = null!;
-
         public MainWindow()
         {
             InitializeComponent();
-            var header = this.FindControl<HeaderView>("Header");
-            var btn = header?.FindControl<Button>("OpenBtn");
-            if (btn == null) return;
-            _openBtn = btn;
-            _openBtn.Click += OpenBtn_Click;
-        }
-
-        private async void OpenBtn_Click(object? sender, RoutedEventArgs e)
-        {
-            var ofd = new OpenFileDialog
-            {
-                AllowMultiple = false,
-                Title = "Open XSD file"
-            };
-            ofd.Filters!.Add(new FileDialogFilter { Name = "XSD schema", Extensions = { "xsd" } });
-            var files = await ofd.ShowAsync(this);
-            if (files is { Length: > 0 })
-            {
-                await ParseAndShowAsync(files[0]);
-            }
-        }
-
-        private Task ParseAndShowAsync(string path)
-        {
-            return Task.Run(() =>
-            {
-                try
-                {
-                    var parser = new XsdSchemaParser();
-                    var model = parser.Parse(path);
-                    Dispatcher.UIThread.Post(() => DataContext = new MainWindowViewModel(model));
-                }
-                catch (Exception ex)
-                {
-                    Dispatcher.UIThread.Post(() => DataContext = new MainWindowViewModel(new SchemaModel { TargetNamespace = ex.Message }));
-                }
-            });
         }
     }
 }

XSDVisualiser.Desktop/Views/HeaderView.axaml.cs

@@ -1,11 +1,77 @@
+using System;
+using System.Threading.Tasks;
+using Avalonia;
 using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Avalonia.Threading;
+using Avalonia.Platform.Storage;
+using XSDVisualiser.Core;
+using XSDVisualiser.Models;
+using XSDVisualiser.Desktop.ViewModels;
 
 namespace XSDVisualiser.Desktop.Views;
 
 public partial class HeaderView : UserControl
 {
+    private readonly Button? _openBtn;
+
     public HeaderView()
     {
         InitializeComponent();
+        _openBtn = this.FindControl<Button>("OpenBtn");
+        if (_openBtn != null)
+        {
+            _openBtn.Click += OpenBtn_Click;
+        }
+    }
+
+    private async void OpenBtn_Click(object? sender, RoutedEventArgs e)
+    {
+        if (TopLevel.GetTopLevel(this) is not Window topLevel)
+            return;
+
+        var storageProvider = topLevel.StorageProvider;
+        var options = new FilePickerOpenOptions
+        {
+            AllowMultiple = false,
+            Title = "Open XSD file",
+            FileTypeFilter =
+            [
+                new FilePickerFileType("XSD schema")
+                {
+                    Patterns = ["*.xsd"]
+                }
+            ]
+        };
+        var results = await storageProvider.OpenFilePickerAsync(options);
+        if (results.Count <= 0) return;
+        
+        var file = results[0];
+        var path = file.TryGetLocalPath();
+        if (!string.IsNullOrEmpty(path))
+        {
+            await ParseAndShowAsync(path!, topLevel);
+        }
+        else
+        {
+            Dispatcher.UIThread.Post(() => topLevel.DataContext = new MainWindowViewModel(new SchemaModel { TargetNamespace = "Selected file is not a local file. Please choose a local .xsd." }));
+        }
+    }
+
+    private Task ParseAndShowAsync(string path, Window hostWindow)
+    {
+        return Task.Run(() =>
+        {
+            try
+            {
+                var parser = new XsdSchemaParser();
+                var model = parser.Parse(path);
+                Dispatcher.UIThread.Post(() => hostWindow.DataContext = new MainWindowViewModel(model));
+            }
+            catch (Exception ex)
+            {
+                Dispatcher.UIThread.Post(() => hostWindow.DataContext = new MainWindowViewModel(new SchemaModel { TargetNamespace = ex.Message }));
+            }
+        });
     }
 }