NodePaintBox

If you need to display data that has no built-in node control support, you can display it manually using the NodePaintBox node control.

Using the NodePaintBox node control involves these steps:

  • Measure the node control size inside a node using the MeasureNodeControl treeview event.
  • Draw data using the PaintNodeControl treeview event.

Example

// 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 treeview, MeasureObjectEventArgs args)
{
    // Measure the node control size according to the specified node
    switch(args.Node.Text)
    {
        case "1":
        args.Size = new Size(20, 20);
        break;

        case "2":
        args.Size = new Size(30, 30);
        break;
    }
}

// Paint the node control content as a red rectangle.
void tree_PaintNodeControl(FlexibleTreeView treeview, NodeControlDrawEventArgs args)
{
    using (Brush br = new SolidBrush(Color.Red))
    {
        args.Context.Graphics.FillRectangle(br, args.Context.Bounds);
    }
}

' Create the node control.
Dim nc As New NodePaintBox()
nc.AttachTo(tree)
' Subscribe to the event to define the node control's size and content.
AddHandler tree.MeasureNodeControl, AddressOf tree_MeasureNodeControl
AddHandler tree.PaintNodeControl, AddressOf tree_PaintNodeControl

' Add nodes, where our data will be displayed.
Dim n As New Node("1")
n.AttachTo(tree)
n = New Node("2")
n.AttachTo(tree)

Private Sub tree_MeasureNodeControl(treeview As FlexibleTreeView, args As MeasureObjectEventArgs)
    ' Measure the node control size according to the specified node
    Select Case args.Node.Text
        Case "1"
            args.Size = New Size(20, 20)
        Case "2"
            args.Size = New Size(30, 30)
    End Select
End Sub

' Paint the node control content as a red rectangle.
Private Sub tree_PaintNodeControl(treeview As FlexibleTreeView, args As NodeControlDrawEventArgs)
    Using br As Brush = New SolidBrush(Color.Red)
        args.Context.Graphics.FillRectangle(br, args.Context.Bounds)
    End Using
End Sub