WPF automatic resize font until it fits within parent control

Frinavale picture Frinavale · Feb 14, 2013 · Viewed 12.9k times · Source

I have a user control who's root element is a Grid.

I also have have a ContentControl that serves as a placeholder for some text that is filled when data is loaded. This control can be moved around within the user control and so it's position can be anywhere.

If the text is too long to fit within the root Grid of the user control, I want to reduce the font size of the ContentControl until the text fits.

My problem is that I can't seem to find an event that I can handle to do this process. I tried using the ContentControl.LayoutUpdated event;however, the sender parameter for this always appears to be nothing...which is really not helpful!

I am really looking forward to any advise on how to achieve this.

Thank you

-Frinny

Answer

John Bowen picture John Bowen · Feb 14, 2013

Wrapping your ContentControl in a Viewbox set to only scale down will do this for you:

<Viewbox StretchDirection="DownOnly" Stretch="Uniform">
    <ContentControl Content="Some Text"/>
</Viewbox>