From ced3c6bd53d91ccc52f5e6d081c37e4f8f4b23e0 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@users.noreply.github.com>
Date: Wed, 12 Sep 2018 23:24:29 +0200
Subject: [PATCH] Demonstrate binding commands.

---
 samples/ControlCatalog/Pages/MenuPage.xaml    |  4 +-
 samples/ControlCatalog/Pages/MenuPage.xaml.cs | 69 +++++++++++++++++--
 2 files changed, 67 insertions(+), 6 deletions(-)

diff --git a/samples/ControlCatalog/Pages/MenuPage.xaml b/samples/ControlCatalog/Pages/MenuPage.xaml
index 6eeb86a00f..c5aa35312c 100644
--- a/samples/ControlCatalog/Pages/MenuPage.xaml
+++ b/samples/ControlCatalog/Pages/MenuPage.xaml
@@ -36,11 +36,13 @@
 
             <StackPanel>
                 <TextBlock Classes="h3" Margin="4 8">Dyanamically generated</TextBlock>
-                <Menu Items="{Binding}">
+                <Menu Items="{Binding MenuItems}">
                     <Menu.Styles>
                         <Style Selector="MenuItem">
                             <Setter Property="Header" Value="{Binding Header}"/>
                             <Setter Property="Items" Value="{Binding Items}"/>
+                            <Setter Property="Command" Value="{Binding Command}"/>
+                            <Setter Property="CommandParameter" Value="{Binding CommandParameter}"/>
                         </Style>
                     </Menu.Styles>
                 </Menu>
diff --git a/samples/ControlCatalog/Pages/MenuPage.xaml.cs b/samples/ControlCatalog/Pages/MenuPage.xaml.cs
index 01add3e76e..ec7c000fe6 100644
--- a/samples/ControlCatalog/Pages/MenuPage.xaml.cs
+++ b/samples/ControlCatalog/Pages/MenuPage.xaml.cs
@@ -1,6 +1,10 @@
 using System.Collections.Generic;
+using System.Reactive;
+using System.Threading.Tasks;
+using System.Windows.Input;
 using Avalonia.Controls;
 using Avalonia.Markup.Xaml;
+using ReactiveUI;
 
 namespace ControlCatalog.Pages
 {
@@ -9,23 +13,35 @@ namespace ControlCatalog.Pages
         public MenuPage()
         {
             this.InitializeComponent();
-            DataContext = new[]
+            var vm = new MenuPageViewModel();
+
+            vm.MenuItems = new[]
             {
                 new MenuItemViewModel
                 {
                     Header = "_File",
                     Items = new[]
                     {
-                        new MenuItemViewModel { Header = "_Open..." },
-                        new MenuItemViewModel { Header = "Save" },
+                        new MenuItemViewModel { Header = "_Open...", Command = vm.OpenCommand },
+                        new MenuItemViewModel { Header = "Save", Command = vm.SaveCommand },
                         new MenuItemViewModel { Header = "-" },
                         new MenuItemViewModel
                         {
                             Header = "Recent",
                             Items = new[]
                             {
-                                new MenuItemViewModel { Header = "File1.txt" },
-                                new MenuItemViewModel { Header = "File2.txt" },
+                                new MenuItemViewModel
+                                {
+                                    Header = "File1.txt",
+                                    Command = vm.OpenRecentCommand,
+                                    CommandParameter = @"c:\foo\File1.txt"
+                                },
+                                new MenuItemViewModel
+                                {
+                                    Header = "File2.txt",
+                                    Command = vm.OpenRecentCommand,
+                                    CommandParameter = @"c:\foo\File2.txt"
+                                },
                             }
                         },
                     }
@@ -40,6 +56,8 @@ namespace ControlCatalog.Pages
                     }
                 }
             };
+
+            DataContext = vm;
         }
 
         private void InitializeComponent()
@@ -48,9 +66,50 @@ namespace ControlCatalog.Pages
         }
     }
 
+    public class MenuPageViewModel
+    {
+        public MenuPageViewModel()
+        {
+            OpenCommand = ReactiveCommand.CreateFromTask(Open);
+            SaveCommand = ReactiveCommand.Create(Save);
+            OpenRecentCommand = ReactiveCommand.Create<string>(OpenRecent);
+        }
+
+        public IReadOnlyList<MenuItemViewModel> MenuItems { get; set; }
+        public ReactiveCommand<Unit, Unit> OpenCommand { get; }
+        public ReactiveCommand<Unit, Unit> SaveCommand { get; }
+        public ReactiveCommand<string, Unit> OpenRecentCommand { get; }
+
+        public async Task Open()
+        {
+            var dialog = new OpenFileDialog();
+            var result = await dialog.ShowAsync();
+
+            if (result != null)
+            {
+                foreach (var path in result)
+                {
+                    System.Diagnostics.Debug.WriteLine($"Opened: {path}");
+                }
+            }
+        }
+
+        public void Save()
+        {
+            System.Diagnostics.Debug.WriteLine("Save");
+        }
+
+        public void OpenRecent(string path)
+        {
+            System.Diagnostics.Debug.WriteLine($"Open recent: {path}");
+        }
+    }
+
     public class MenuItemViewModel
     {
         public string Header { get; set; }
+        public ICommand Command { get; set; }
+        public object CommandParameter { get; set; }
         public IList<MenuItemViewModel> Items { get; set; }
     }
 }