How can I make a tree view re-think whether or not a horizontal scroll bar is needed?

Question

Consider the following very simple unit:

Unit1.pas

unit Unit1;

interface

uses
  Windows, Classes, Controls, Forms, ComCtrls;

type
  T         


        

Answer 1

Very simple, use TreeView1.Items.BeginUpdate/EndUpdate methods and the scrollbar will be calculated accordingly.

like this:

...
 TreeView1.Items.BeginUpdate;
 // change your nodes here
 TreeView1.Items.EndUpdate