error: 'QIcon' is an incomplete type

Aphrodites

I am beginning to learn Qt and want to test icons. I am on a MacBook Pro 2018 running MacOS 10.14 and Qt 3.0.6. I put this line in my main.cpp:

window.setWindowIcon(QIcon("logo.png"));

I have an error now that says:

qttest.cpp:18:26: error: 'QIcon' is an incomplete type
    window.setWindowIcon(QIcon("logo.png"));
                         ^
/usr/local/Cellar/qt/5.12.0/lib/QtCore.framework/Headers/qmetatype.h:1971:1: note: 
      forward declaration of 'QIcon'
QT_FOR_EACH_STATIC_GUI_CLASS(QT_FORWARD_DECLARE_STATIC_TYPES_ITER)
^
/usr/local/Cellar/qt/5.12.0/lib/QtCore.framework/Headers/qmetatype.h:153:18: note: 
      expanded from macro 'QT_FOR_EACH_STATIC_GUI_CLASS'
    F(QIcon, 69, QIcon) \
                 ^
1 error generated.

My main.pro has QT += core and QT += widgets, and nothing else. What is wrong with my installation of Qt? How to refresh my installation? What should I do?

Chris Kawa

Hi, welcome to the forum.
Seems you're just missing an include: #include <QIcon>.