Question

我有一个窗口，我可以在其中基于单击的内容来编辑特定对象。它会按应打开的方式填充所有TextBox，甚至是DatePicker，但ComboBox开头为空。我在这里发现了一些类似的问题，但是他们提供的解决方案没有任何改变。

XAML代码：

<ComboBox Name="Position" 
Grid.Row="5" 
SelectedIndex="{Binding SelectedIndex}"
SelectedItem="{Binding Position}" 
ItemsSource="{Binding Positions}" 
DisplayMemberPath="Position"
Style="{StaticResource MaterialDesignComboBox}"
IsEnabled="True"
IsEditable="False"
IsReadOnly="True"
Margin="15,1,15,1" 
FontSize="12"/>

.cs

        WindowAddEditEmployeesViewModel employee = new WindowAddEditEmployeesViewModel();
        public WindowEditEmployees(int id, string firstName, string lastName, string position, string email, string phoneNumber, string address, string postalCode, string city, string login, string password, Nullable<DateTime> dateOfBirth)
        {
            InitializeComponent();

            employee.Positions = new ObservableCollection<PositionsViewModel>(positionsMethods.GetAll());

            employee.idEmployee = id;
            employee.FirstName = firstName;
            employee.LastName = lastName;
            employee.Position = position;
            employee.Email = email;
            employee.PhoneNumber = phoneNumber;
            employee.Address = address;
            employee.PostalCode = postalCode;
            employee.City = city;
            employee.Login = login;
            employee.Password = password;
            employee.DateOfBirth = dateOfBirth;

            employee.SelectedIndex = Array.IndexOf(employee.Positions.ToArray(), employee.Position);

            DataContext = employee;
        }

ViewModel：

    public class WindowAddEditEmployeesViewModel : EmployeesViewModel, INotifyPropertyChanged
    {
        public ObservableCollection<PositionsViewModel> Positions { get; set; }
        public int SelectedIndex { get; set; }

        new public event PropertyChangedEventHandler PropertyChanged;
    }

基本视图模型包含FirstName，LastName等内容。

因此，从代码中可以看到它应该正常工作，SelectedIndex和SelectedItem均已正确设置，但它拒绝工作。

WPF ComboBox不显示带有SelectedIndex的默认值

0 个答案: