Scale window programatically in winUI3

[khoabui1412]

Hi,
Is there a way to scale the window programatically in winUI3 app, instead of changing scale in system setting?
And how to prevent scale the window automatically if dpt changed in system setting?

[castorix]

I'm not sure what you're trying to do but you can get the scaling with XamlRoot.RasterizationScale or GetDpiForWindow and you can get notified with XamlRoot.Changed
For an idea, I used XamlRoot.Changed in a UserControl to resize a hosted Win32 control in this test sample : ContainerPanel.xaml.cs

[khoabui1412]

I have the scale custom setting in my app, I want when change the scale for example to 200%, all windows will scale to 200%.
I can resize the window to 200% but it's not literally scale to 200%, and I need to implement scale for every UIelement inside.
So I want to know the mechanism in scaling app when change scale in system setting, then I can do the same.

[DHancock]

A ScrollViewer control may be what you're after. Wrap any content that you want to zoom in the ScrollViewer, then to set the zoom factor call ScrollViewer.ChangeView() from your code behind. There is an example in the WinUI3 Gallery app. (edit: using ZoomToFactor() isn't recommended)

[khoabui1412]

I think it's still not a correct scale, there will be conflict in resize window and scale Ui element,
In this case view can be cropped.