public void TestCommand() { var vm = new LayoutFieldViewModel(); var layoutViewModel = Mock.Create<LayoutViewModel>(); layoutViewModel.LayoutList = new ObservableCollection<LayoutFieldViewModel>() { new LayoutFieldViewModel() { ColumnName = "ColName", ColumnSystemName = "ColumnSystemName" } }; vm.Initialize(string.Empty, string.Empty, layoutViewModel); Assert.IsNotNull(vm.ReturnColumnCommand); }