From 065f3b76bb2d2e07082175164f61b2f3ba03b864 Mon Sep 17 00:00:00 2001
From: Dan Walmsley <dan@walms.co.uk>
Date: Mon, 9 Sep 2019 20:49:33 +0100
Subject: [PATCH] add a repro to control catalog.

---
 samples/ControlCatalog/Pages/ListBoxPage.xaml |  4 +++-
 .../ControlCatalog/Pages/ListBoxPage.xaml.cs  | 21 ++++++++++++++++++-
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/samples/ControlCatalog/Pages/ListBoxPage.xaml b/samples/ControlCatalog/Pages/ListBoxPage.xaml
index 49e9aafc4a..b1b3112e60 100644
--- a/samples/ControlCatalog/Pages/ListBoxPage.xaml
+++ b/samples/ControlCatalog/Pages/ListBoxPage.xaml
@@ -10,12 +10,14 @@
               HorizontalAlignment="Center"
               Spacing="16">
       <StackPanel Orientation="Vertical" Spacing="8">
-        <ListBox Items="{Binding Items}" SelectedItems="{Binding SelectedItems}" SelectionMode="{Binding SelectionMode}" Width="250" Height="350"></ListBox>
+        <ListBox Items="{Binding Items}" SelectedItem="{Binding SelectedItem}" AutoScrollToSelectedItem="True"  SelectedItems="{Binding SelectedItems}" SelectionMode="{Binding SelectionMode}" Width="250" Height="350"></ListBox>
 
         <Button Command="{Binding AddItemCommand}">Add</Button>
 
         <Button Command="{Binding RemoveItemCommand}">Remove</Button>
 
+        <Button Command="{Binding SelectRandomItemCommand}">Select Random Item</Button>
+
         <ComboBox SelectedIndex="{Binding SelectionMode, Mode=TwoWay}">
           <ComboBoxItem>Single</ComboBoxItem>
           <ComboBoxItem>Multiple</ComboBoxItem>
diff --git a/samples/ControlCatalog/Pages/ListBoxPage.xaml.cs b/samples/ControlCatalog/Pages/ListBoxPage.xaml.cs
index 8a67766c76..cdbf8fd2b6 100644
--- a/samples/ControlCatalog/Pages/ListBoxPage.xaml.cs
+++ b/samples/ControlCatalog/Pages/ListBoxPage.xaml.cs
@@ -1,3 +1,4 @@
+using System;
 using System.Collections.ObjectModel;
 using System.Linq;
 using System.Reactive;
@@ -27,7 +28,7 @@ namespace ControlCatalog.Pages
 
             public PageViewModel()
             {
-                Items = new ObservableCollection<string>(Enumerable.Range(1, 10).Select(i => GenerateItem()));
+                Items = new ObservableCollection<string>(Enumerable.Range(1, 10000).Select(i => GenerateItem()));
                 SelectedItems = new ObservableCollection<string>();
 
                 AddItemCommand = ReactiveCommand.Create(() => Items.Add(GenerateItem()));
@@ -39,16 +40,34 @@ namespace ControlCatalog.Pages
                         Items.Remove(SelectedItems[0]);
                     }
                 });
+
+                SelectRandomItemCommand = ReactiveCommand.Create(() =>
+                {
+                    var random = new Random();
+
+                    SelectedItem = Items[random.Next(Items.Count - 1)];
+                });
             }
 
             public ObservableCollection<string> Items { get; }
 
+            private string _selectedItem;
+
+            public string SelectedItem
+            {
+                get { return _selectedItem; }
+                set { this.RaiseAndSetIfChanged(ref _selectedItem, value); }
+            }
+
+
             public ObservableCollection<string> SelectedItems { get; }
 
             public ReactiveCommand<Unit, Unit> AddItemCommand { get; }
 
             public ReactiveCommand<Unit, Unit> RemoveItemCommand { get; }
 
+            public ReactiveCommand<Unit, Unit> SelectRandomItemCommand { get; }
+
             public SelectionMode SelectionMode
             {
                 get => _selectionMode;