C# WPF - ScrollViewer + TextBlock troubles

Question

I have a TextBlock within a ScrollViewer that aligns with stretch to its window. I need the TextBlock to behave as the following:

Answer 1

Without more detail, the best I can do is provide the standard way of doing this. Basically, host your element (which has a minimum size) in a scroll viewer; when the scrollviewer is resized small enough such that the element cannot wholly fit inside it, it will automatically display scroll bars. Example:

<ScrollViewer>
    <Button MinWidth="100" MinHeight="50"/>
</ScrollViewer>

Answer 2

If you have more complicated layout and cannot bind to the ScrollViewer then the IgnoreWidthControl in the answer https://stackoverflow.com/a/41281041/254109 may help.

Answer 3

This works:

<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <ScrollViewer HorizontalScrollBarVisibility="Auto" 
                  VerticalScrollBarVisibility="Auto"
                  Name="Scroller">
        <TextBlock HorizontalAlignment="Stretch"
                   VerticalAlignment="Stretch"
                   MinWidth="100"
                   Width="{Binding ElementName=Scroller, Path=ViewportWidth}"
                   TextWrapping="Wrap"
                   Text="Some really long text that should probably wordwrap when you resize the window." />
    </ScrollViewer>
</Window>