Super odd DarkMode problem

Beatrix_Willius · September 2, 2020, 10:39am

If I start my app in LightMode the app can switch to DarkMode and back fine. If I start the app in DarkMode then the app doesn’t switch to LightMode.

App started in DarkMode:

Switched to LightMode:

I’m at a loss what I can do to fix the problem. So far I have:

removed code for handling display changes
removed all pre and post build scripts
copied all external classes, icons and what not to a new project

Problem shows up for 10.14 and 10.15. I had a user test and he sees the same problem. Only the main app is affected and not the helper apps.

Does anyone have an idea what I could change/check/do?

Sam_Rowlands · September 2, 2020, 12:57pm

That is super weird.

Do you get the same behavior with a blank project?

Beatrix_Willius · September 2, 2020, 1:08pm

Nope. A blank project works fine. My helper apps also work fine.

I tested with 2019r3 and 2020r1. Both show the same problem.

DerkJ · September 2, 2020, 1:13pm

The events AppearnceChanged do fire ?

Beatrix_Willius · September 2, 2020, 1:35pm

The AppearanceChanged event fires. I have a notification that does to open windows which then gets colours. Like this:

if Color.IsDarkMode then
  Return kWindowBackGroundDM
else
  Return kWindowBackGround
end if

The app still thinks it’s DarkMode.

Norman_Palardy · September 2, 2020, 1:44pm

It used to be the case that when Appearance Changed fired it was too soon to do the correct assessment of what colors to grab
You can / should only do that in paint events AFTER that event has fired

Beatrix_Willius · September 2, 2020, 1:57pm

@Norman Palardy: if that were the case then I should have problems when starting in LightMode, too. Also the whole app doesn’t switch as you can see in the black toolbar.

But testing is always good. I added an App.SleepCurrentThread(100) to the AppearanceChanged event. And there is no change in behaviour.

Norman_Palardy · September 2, 2020, 2:00pm

All I can say is that in my largest app I have waited until the next paint event to grab the correct colors and never have this issue going either way regardless of what mode I started in

Beatrix_Willius · September 2, 2020, 2:08pm

The colours aren’t the problem. If they were then I would end up in a sort of Frankenstein mode. If you look at the toolbar then you can see that the complete app is in DarkMode. If I open new windows they are also in DarkMode.

Norman_Palardy · September 2, 2020, 2:49pm

New windows open AFTER the appearance changed event has completed and so asking “if I’m in dark mode” works

Beatrix_Willius · September 2, 2020, 2:51pm

New windows open in DarkMode even after switching to LightMode for my application!

Norman_Palardy · September 2, 2020, 2:55pm

what version of Xojo ?
does this behaviour change if you move back to an older version ?
reboot does it persist ?

DerkJ · September 2, 2020, 3:11pm

What happens if you hide the window(s) when you change, then show the window(s) again ?

Beatrix_Willius · September 2, 2020, 3:38pm

Xojo versions: 2019r3 and 2020r1
Older version: going to test tomorrow. Also going to test older versions of my app.
Rebooting: yes, the problem persists.
Window hiding: doesn’t make a difference.

Martin_Fitzgibbons · February 19, 2021, 10:58pm

Did you get a resolution?

Beatrix_Willius · February 20, 2021, 4:19am

Nope, problem still shows up for latest BS and Xojo 2020r2.1:

Markus_Winter · February 20, 2021, 5:32am

Can you manually set it to DarkMode / LightMode? E.g.

  
  UseDarkMode = DarkMode
  
  // can we simulate dark mode 
  Dim nsWindowObj As NSWindowMBS
  Dim appearanceObj As NSAppearanceMBS
  
  nsWindowObj = w.NSWindowMBS
  
  
  If IsDarkMode Or UseDarkMode Then  // use DarkMode
    appearanceObj = NSAppearanceMBS.appearanceNamed(NSAppearanceMBS.NSAppearanceNameVibrantDark)
    
  Else
    appearanceObj = NSAppearanceMBS.appearanceNamed(NSAppearanceMBS.NSAppearanceNameVibrantLight)
    
  End If
  
  If appearanceObj <> Nil Then
    NSAppearanceMBS.setAppearance(w, appearanceObj)
  End If
End Sub

You might be able to test for the color shown and try to set the mode manually accordingly.

Markus_Winter · February 20, 2021, 5:32am

Oh, and I presume you checked with Arbed for project corruption …?

Beatrix_Willius · February 20, 2021, 9:06am

Yes, I already imported everything into a new project. The effect was the same.

Big thanks for the code. This works fine.

Steve_Upton · February 20, 2021, 11:32pm

Marcus, I’m not sure I understand the implications here…

Does this mean I can switch a darkmode-capable app into dark mode even when the macOS is not in dark mode? (or vice versa)