QWidget::paintEngine() should no longer be called

[Greeny]

In Qt 4.1 I get the following error when trying to use QPainter in a function in a QLineEdit derived class:


QWidget::paintEngine() should no longer be called
QPainter::begin(), paintdevice returned engine == 0, type: 1


This is on Linux and I have tried to set:

setAttribute( Qt::WA_PaintOutsidePaintEvent, true );

setAttribute( Qt::WA_PaintOutsidePaintEvent, true );

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as this painting is not happening in the paintEvent() function.

The line that triggers the message is:

QPainter painter(this);

QPainter painter(this);

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Nothing is painted using the painter. Is this not possible to do or how could I paint in this function ?

[wysota]

Does "this" point to a widget?

[aamer4yu]

Where are u using the line
QPainter painter(this) ??

[Greeny]

The line is in the ::event(QEvent*) function of a class that is derived from a QLineEdit.

[wysota]

Hmm.... Why not do it the regular way - using paintEvent? Everything you draw in event will right away get discarded because the paintEvent will be called and it'll draw a regular line edit.

[Greeny]

Sure it could be rewritten, but the code works fine in Qt < Qt4 and I was kind of curious if it could be done in the same way to ease the porting.

[wysota]

The gap between Qt3 and Qt4 is very big, some concepts have changed, painting included.

[Greeny]

Well if there are no shortcuts I have to walk the long way, thanks anyway.