User defined painting not visible

Question

I have a Windows Forms application with a GroupBox, and a PictureBox as background image, and several clickable OvalShapes from the PowerPack.

Now I need some labels for the OvalShapes, so I put a EventHandler on my GroupBox that on every repaint, the following should be drawn

this.groupBoxTest.Paint += new System.Windows.Forms.PaintEventHandler(this.groupBoxVirtualView_Paint);

private void groupBoxVirtualView_Paint(object sender, PaintEventArgs e)
{
    Graphics g = groupBoxVirtualView.CreateGraphics();//e.Graphics;
    g.DrawString("01", new Font("Arial", 12), new SolidBrush(Color.Black), 240, 115);
}

But the string 01 never gets drawn; all I see are the oval shapes that are at the same position - disabling them for testing purpose doesn't do it either.

What's happening to my string?

Any other way to label my PoweredOval?

Answer 1

You have to use

groupBoxVirtualView.Invalidate();

to repaint the groupBox!

Answer 2

The paint event should use the graphic object from the sender:

private void groupBoxVirtualView_Paint(object sender, PaintEventArgs e)
{
  Graphics g = e.Graphics;
  g.DrawString("01", new Font("Arial", 12), new SolidBrush(Color.Black), 240, 115);
}

Also, if there is a PictureBox inside the GroupBox, that control will not show any of the GroupBox paintings to come through the control. It will hide it.