How to detect tab selection in TabBarSplitterControl?

//The event will raised before the selected tab index changing
this.tabBarSplitterControl1.Bar.SelectedIndexChanging += new Syncfusion.Windows.Forms.SelectedIndexEventHandler(Bar_SelectedIndexChanging);
//The event will raised after the selected tab index changed
this.tabBarSplitterControl1.Bar.SelectedIndexChanged += new Syncfusion.Windows.Forms.SelectedIndexEventHandler(Bar_SelectedIndexChanged);
 
private void Bar_SelectedIndexChanging(object sender, Syncfusion.Windows.Forms.SelectedIndexEventArgs e)
{
 MessageBox.Show("SelectedIndexChanging is " + e.Tab.ToString());
}
 
private void Bar_SelectedIndexChanged(object sender, Syncfusion.Windows.Forms.SelectedIndexEventArgs e)
{
 MessageBox.Show("SelectedIndexChanged is " + e.Tab.ToString());
}

'The event will raised before the selected tab index changing
AddHandler Me.tabBarSplitterControl1.Bar.SelectedIndexChanging, AddressOf Bar_SelectedIndexChanging
'The event will raised after the selected tab index changed
AddHandler Me.tabBarSplitterControl1.Bar.SelectedIndexChanged, AddressOf Bar_SelectedIndexChanged
 
Private Sub Bar_SelectedIndexChanging(ByVal sender As Object, ByVal e As Syncfusion.Windows.Forms.SelectedIndexEventArgs)
 MessageBox.Show("SelectedIndexChanging is " & e.Tab.ToString())
End Sub
 
Private Sub Bar_SelectedIndexChanged(ByVal sender As Object, ByVal e As Syncfusion.Windows.Forms.SelectedIndexEventArgs)
 MessageBox.Show("SelectedIndexChanged is " & e.Tab.ToString())
End Sub