NodePaintBox node control

// create the node control.
NodePaintBox nc = new NodePaintBox();
nc.AttachTo(tree);
// subscribe to the event to define the node control`s size and content.
tree.MeasureNodeControl += tree_MeasureNodeControl;
tree.PaintNodeControl += tree_PaintNodeControl;
 
// add nodes, where our data will be displayed.
Node n = new Node("1");
n.AttachTo(tree);
n = new Node("2");
n.AttachTo(tree);
 
private void tree_MeasureNodeControl(FlexibleTreeView pTreeview, MeasureObjectEventArgs pArgs)
{
  // measure the node control size according to the specified node
  switch(pArgs.Node.Text)
  {
    case "1":
      pArgs.Size = new Size(20, 20);
      break;
 
    case "2":
      pArgs.Size = new Size(30, 30);
      break;
  }
}
 
// paint the node control content as a red rectangle.
void tree_PaintNodeControl(FlexibleTreeView pTreeview, NodeControlDrawEventArgs pArgs)
{
  using (Brush br = new SolidBrush(Color.Red))
  {
    pArgs.Context.Graphics.FillRectangle(br, pArgs.Context.Bounds);
  }
}