How to get triggers the event when a toolbar is dragged to a float state in WinForms CommandBar?

CommandBar cbar = this.mainFrameBarManager1.GetCommandBarManager().GetCommandBarFromBar(this.bar1);
cbar.ParentChanged += new EventHandler(cbar_ParentChanged);
void cbar_ParentChanged(object sender, EventArgs e)
{
   this.textBox1.Text = "Parent Changed";
}

Dim commandBar As CommandBar = Me.MainFrameBarManager1.GetCommandBarManager().GetCommandBarFromBar(Me.Bar1)
AddHandler commandBar.ParentChanged, AddressOf commandBar_ParentChanged
Private Sub commandBar_ParentChanged(ByVal sender As Object, ByVal e As EventArgs)
   Me.TextBox1.Text = "Parent Changed"
End Sub