Repainting widget

[fear]

Thank You. That's true. In fact api doc doesn't say it in explicit way. I was always using QPainter in this way:

Mostly, all this is done inside a paint event. (In fact, 99% of all QPainter use is in a reimplementation of QWidget::paintEvent(), and the painter is heavily optimized for such use.) Here's one very simple example:

void SimpleExampleWidget::paintEvent()
    {
        QPainter paint( this );
        paint.setPen( Qt::blue );
        paint.drawText( rect(), AlignCenter, "The Text" );
    }

void SimpleExampleWidget::paintEvent()
    {
        QPainter paint( this );
        paint.setPen( Qt::blue );
        paint.drawText( rect(), AlignCenter, "The Text" );
    }

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So now I realized that it MUST be used in such way.