‘QPainter painter’ has initialiser but incomplete type
If you ever got an error something like [some-class] has initialiser but incomplete type, it basically means the compiler cannot understand the type and you need to add the include for it. 1 2 3 4 5 QPixmap pixmap(20,10); pixmap.fill(Qt::white); QPainter painter(&pixmap); QPen pen(Qt::blue); Take the code snipped above when you compile it you might get an error something along the lines of the following for line 4. ...