drawRect inside paintGL()

[mickey]

I understand; updateGL(9 doesn't call paint event; update() insted, yes!
I change this below and now rect is visible (but flickering);

void myMainForm::myUpdateWidgets() {
	if (this->MultipleView->isShown()){
		myWidget2->update();
		myWidget3->update(); 
           ..........................................
}

void myMainForm::myUpdateWidgets() {
	if (this->MultipleView->isShown()){
		myWidget2->update();
		myWidget3->update(); 
           ..........................................
}

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But now arise another problem: the update of widget2 is not fuid! I know updateGL() calls paintGL immediately; update() schedule the call to paintGL() for when widgetGL need an update; I suspect that in my multipleView (I can see wid2 and wid3) widget3 is the last drawn; and paintGL() for widget2 starts later than necessay. Can be the truth?
How can avoid this? Thanks