[Qt-creator] Error compiling: PlaceholderText is not a member of QPalette

[Julius Bullinger]

On 13.12.2018 17:28, Murphy, Sean wrote:
> I had an application that compiled just fine yesterday using Qt 5.9.6
> and Qt Creator 4.7.x (sorry, can't remember the last digit, it might
> have been 2?). Today I made two changes before my next compilation
> attempt: I upgraded to Qt Creator 4.8.0 (revision d51ddbb8f0), and I
> edited my mainwindow.ui file in Qt Creator 4.8.0's form editor. Now
> when I attempt to compile I get multiple compile errors all of which
> are in the ui_mainwindow.h file, and all are: 'PlaceholderText' is
> not a member of 'QPalette'
> 
> [...]
> 
> I'm mostly tossing this here in case someone stumbles across the same
> issue, but if anyone has any thoughts on how to avoid this from
> happening in the first place, I'd appreciate it.
I just had the same issue happen yesterday, which I reported as 
QTCREATORBUG-21698. The solution suggested by Friedemann is to use the 
Designer that came bundled with your Qt version, not the one integrated 
in Creator.

I don't agree with the assessment (I think the IDE should _never_ create 
invalid code for the selected toolchain), but at least it's a workaround.

Thus, I have disabled the Widget Designer plugin in Creator, and am 
using the stand-alone Designer instead.

Hope that helps.

Regards,
Julius