Cannot use QRect::setWidth

[WilliamSpiderWeb]

When I try to set the width of a modified QDockWidget

int iWidth = 500;
this->geometry().setWidth(iWidth);

int iWidth = 500;
this->geometry().setWidth(iWidth);

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I get the following error.

passing 'cost QRect' as 'this' argument of 'void QRect::setWidth(int)' discards qualifier

I have no idea what that error means and why I can't use such a simple function.

[wysota]

It means you are trying to modify an object that is const.

[ChrisW67]

passing 'const QRect' as 'this' argument of 'void QRect::setWidth(int)' discards qualifier

Contains two clues. You have a constant object that you are trying to use a non-const method on. The "discards qualifier" refers to attempting to discard the "const". This is an error and basic C++.

QWidget::geometry() is defined:

const QRect &	geometry () const

const QRect &	geometry () const

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You cannot modify a const QRect.

You can modify the geometry through the QWidget::setGeometry() method.

[WilliamSpiderWeb]

Thank you,
that was really stupid...

When I read your post I remembered that I used setGeometry() before.