I have a question: I have a window with a TextArea and a Tab-panel with three tabs.
When I switch ‘Supports Hi-DPI’ on, the app crashes on ‘Window1.show’ with: An exception of class NilObjectException was not handled. The application must shut down.
What I see on screen is that Window1 has been opened and is visible, the List is present on that window, but the Tab-panel is not.
So I suspect the crash occurs possible because of the Tab-panel.
Inside the three tabs, there are only these normal controls: TextFields, TextAreas, PopupMenus, CheckBoxes, RadioButtons and PushButtons.
There are no graphics or images on that window nor inside the three tabs.
I tried to compile with the 64-bit switched on, but I got the same error on the same line.
Do you have code in the Open event handlers for any of the controls? Those events happen before the window’s Open event. In particular, you will run into problems if the control Open event handlers refer to other controls on the window.
I think we are saying the same thing. Maybe I didn’t express myself clearly.
The OP said it happened with or without the 64-bit setting on. Turning on HiDPI is apparently what makes it crash; not that this setting is likely to change the event order either.
It happens with the debugger and the compiled version. As I see it now, it happens during the window-opening process, because, as I wrote, the window is indeed opened, the first control (the textarea) is visible and then it crashes. And that moment is when it is building the tabbed-control.
And as said, no pictures or graphics. Just standard controls.
What is the position of ImplicitInstance on your Window1? Did you switch it off incidentally?
(Doesnt sound so because you say it opens; but there must be a reason the debugger stops there with that exception.)
No, it would cause an exception under low res as well. Was just a wild guess.
Is it possible to make a small project just with that window? Does it crash too?
And like Urs asked: Do your controls have open event handlers?
Did you examine the system crash log?