public MainWindow()
{
InitializeComponent();
SoftwareEngineer Henk = new SoftwareEngineer("Henk", 54);
SoftwareEngineer Gerard = new SoftwareEngineer("Gerard", 30);
SoftwareEngineer Peter = new SoftwareEngineer("Peter", 28);
SoftwareArchitect Pieter = new SoftwareArchitect("Pieter", 43);
TeamLead Jan = new TeamLead(new SoftwareArchitect("Jan", 50));
TeamLead Pierri = new TeamLead(new SoftwareArchitect("Pierri", 50));
Jan.Add(Gerard);
listOfEmployees.ItemsSource = AllEmployeeList;
}