internal void Expand(bool expand)
{
    IDesignerHost host = GetService(typeof(IDesignerHost)) as IDesignerHost;
    if (host == null)
        return;

    this.SuspendLayout();

    CompositeActivity root = host.RootComponent as CompositeActivity;
    foreach (Activity activity in root.Activities)
    {
        CompositeActivityDesigner compositeActivityDesigner = host.GetDesigner((IComponent)activity) as CompositeActivityDesigner;
        if (compositeActivityDesigner != null)
        {
            compositeActivityDesigner.Expanded = expand;
        }
    }

    this.ResumeLayout(true);
}