Drawing over content widgets? (overlay)

[sertrem]

I do have a widget that is composed of some other widgets, and I want to draw something over it, how can I do that?

At first I thought that Just drawing on the paintEvent(...) should be enought, but it gets drawn under the contained widgets. Then I though about forcing to draw the children first, then my paint event... but no luck again. Basic example code looks like this:

class PaintWidget : public QWidget{
Q_OBJECT
  public:
    PaintWidget(QWidget *parent){
      b=new MyPushButton("Hello world",this);
    }
 
  protected:
    virtual void paintEvent(QPaintEvent *event){
      b->repaint();
      QPainter p(this);
      p.setPen(QColor("red"));
      p.drawLine(0,0,width(),height());
      event->ignore();
    }
    MyPushButton *b;
};

class PaintWidget : public QWidget{
Q_OBJECT
  public:
    PaintWidget(QWidget *parent){
      b=new MyPushButton("Hello world",this);
    }
    
  protected:
    virtual void paintEvent(QPaintEvent *event){
      b->repaint();
      QPainter p(this);
      p.setPen(QColor("red"));
      p.drawLine(0,0,width(),height());
      event->ignore();
    }
    MyPushButton *b;
};

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Then I thought also to force by hand redrawing calling the paintEvent on the children first, and hiding the widget... But a "QPainter::begin: Widget painting can only begin as a result of a paintEvent" message tells me I can not do it in this way.

Anybody any idea?

(looking at the designer source code I dont get any clear idea on how to do it)

At http://www.monasteriomono.org/.../PaintWidget.tgz I put the full example.

thanks!