WPF application window not scaled on second monitor

0
votes

My WPF application window is not scaled on the second monitor, running Windows 10.1607. The built-in monitor runs at 200% (high DPI) and the external monitor at 100% scaling. Most other program windows change their size and internal scaling when they are moved between monitors, but mine does not. It appears huge on the external monitor, and has double the icon and text size compared to correct scaling.

The application targets .NET Framework 4.0 and the app.manifest file contains the relevant entries for Windows 10 support and dpiAwareness. Even if I remove these entries, it doesn't change. I don't know whether this has worked before, I couldn't find an old version that does.

What do I need to do to let Windows scale my window on a different-DPI monitor just as any other window? I don't currently expect it to be sharp (.NET 4.6.2 has news to that), blurry rescaling is okay. But it just needs to do anything and not render the window at 200% on a 100% monitor.

1
c#wpfwindows
Have you tried flipping the monitors? Does it also show as half size when you make the other monitor the primary monitor? – Thomas Weller
I had issues similar like yours, when I was using StackPanel instead of Grid. But that might be a quite different story. – aniski
Umm, whatever has happened, the monitor flipping and the necessary logoff and login have fixed the issue. My window now scales appropriately when I move it to the other monitor. It already did after selecting the external monitor as primary, and still does now that I have switched it back. Maybe Windows 10 should be restarted more often? – ygoe

1 Answers

0
votes

Seems to be a Windows/Surface bug. Every time I resume the Surface Pro 4 (all updates installed) from standby, a number of applications are not rescaled when moved to another monitor. After a logoff and logon, it works normally again.