public MainWindow() { InitializeComponent(); p = new Presenter(this); //Initialize cbDepList ObservableCollection <Department> depList = p.GetDepList(); foreach (var dep in depList) { cbDepartmentsList.Items.Add($"{dep.Name}, {dep.Location}, {dep.Salary}"); } ////Dep btnNewDep.Click += delegate { p.AddDepartment(); }; btnDeleteDep.Click += delegate { p.DeleteDepartment(); }; ////Emp btnNewEmp.Click += delegate { p.AddEmployee(); }; btnDeleteEmp.Click += delegate { p.DeleteEmployee(); }; lvEmployee.SelectionChanged += delegate { p.RefreshDepartmentsListOnEMP(); }; btnAddDepToEMP.Click += delegate { p.AddDepartmentToEMP(); }; btnDelDepFromEMP.Click += delegate { p.DeleteDepartmentFromEMP(); }; }