Best Way to Scroll to End of ScrollViewer

Question

Currently, the only way I have gotten my code to auto scroll to the end when I add a new item is the following:

XAML:

<ScrollViewer x:Name="chatViewScroller" HorizontalAlignment="Left" Height="201" Margin="0,32,0,0" VerticalAlignment="Top" Width="475" Background="#7FFFFFFF">
    <StackPanel x:Name="chatViewContent" />
</ScrollViewer>

Code:

                chatViewContent.Children.Add(
                    new TextBlock() {
                        Text = text,
                        FontSize = 18,
                        TextWrapping = Windows.UI.Xaml.TextWrapping.Wrap,
                        Margin = new Thickness(10, 3, 10, 0),
                        Foreground = new Windows.UI.Xaml.Media.SolidColorBrush(
                            isServerMessage ? Windows.UI.Colors.Purple : Windows.UI.Colors.Black)
                    });
                await Task.Delay(10);
                chatViewScroller.ScrollToVerticalOffset(chatViewScroller.ScrollableHeight);

Is this the accepted way of doing it? Do I have to wait for some random period of time?

Answer 1

Using ActualHeight did not work for me (I have yet to figure out why) - but using ScrollableHeight like this did the the trick:

// adding item to ItemsControl...
// ...
_scrollViewer.UpdateLayout();
_scrollViewer.ScrollToVerticalOffset(_scrollViewer.ScrollableHeight);

Answer 2

For Windows Phone 8.1 I use this:

MyScrollViewer.ChangeView(0.0f, double.MaxValue, 1.0f);

Answer 3

In my opinion best option is to inherit from ScrollViewer in following way:

public partial class AutoScrollViewer
{        
    public AutoScrollViewer()
    {
        InitializeComponent();
        this.SizeChanged += (sender, args) => this.ScrollToBottom();
    }
}

and XAML

<ScrollViewer x:Class="AutoScrollViewer"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
</ScrollViewer>

Then you can use directly in XAML the new class without additional code behind which is usefull especailly when you have "pure" MVVM code.