c# - 从其他窗口中刷新组合框列表，MVVM

我正在处理某些应用程序，但有一个问题。
我有两个窗口(预订-父级和 guest -子级)。在父窗口中，我有一个包含 guest 列表的组合框和一个用于添加新 guest 的按钮。当我单击该按钮时，“ guest ”窗口(子窗口)打开。在子窗口中，我正在向数据库中添加新的 guest ，并且工作正常。
我的问题是:在子窗口中添加新 guest 后，如何在父窗口中刷新/更新组合框列表？我知道应该在 View 中反射(reflect)该属性的更改，而无需从数据库中检索数据(由于绑定(bind))。

Bookings.xaml

    <ComboBox ItemsSource="{Binding Path=Guests}" SelectedItem="{Binding Path=Guest}" Height="25" HorizontalAlignment="Left" IsEditable="True" IsTextSearchEnabled="True" Margin="119,10,0,0" Name="cbGuest" Padding="3,1,1,1"  TextSearch.TextPath="Name" VerticalAlignment="Top" VerticalContentAlignment="Center" Width="141" FontFamily="Times New Roman" FontWeight="Bold" FontSize="14">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <TextBlock DataContext="{Binding}" Text="{MultiBinding StringFormat='\{0\} ', Bindings={Binding Path=Name}}" />
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>
    <Button BorderBrush="Black" Command="{Binding Path=btnAddGuest}" Content="Novi Gost" FontFamily="Times New Roman" FontWeight="Bold" Height="25" HorizontalAlignment="Left" IsDefault="True" Margin="266,10,0,0" Name="btnNewGuest" VerticalAlignment="Top" Width="62" />

BookingsViewModel.cs

    private tblGuest guest;
    public tblGuest Guest    // Selected guest from combo box
    {
        get
        {
            return guest;
        }
        set
        {
            guest = value;
            OnPropertyChanged("Guest");
        }
    }

    private ObservableCollection<tblGuest> guests;
    public ObservableCollection<tblGuest> Guests    // Guests list in the combo box
    {
        get
        {
            return guests;
        }
        set
        {
            guests = value;
            OnPropertyChanged("Guests");
        }
    }

    public ICommand _btnAddGuest;
    public ICommand btnAddGuest    // Command for opening child window
    {
        get
        {
            if (_btnAddGuest == null)
            {
                _btnAddGuest = new DelegateCommand(delegate()
                {
                    try
                    {
                        Guests guest = new Guests();
                        guest.ShowDialog();
                    }
                    catch
                    {
                        Trace.WriteLine("working...", "MyApp");
                    }
                });
            }
            return _btnAddGuest;
        }
    }

Guests.xaml

    <Button Command="{Binding Path= btnAddGuest}" Content="Dodaj" FontFamily="Times New Roman" FontWeight="Bold" Height="36" HorizontalAlignment="Left" Margin="12,402,0,0" Name="btnAddGuest" VerticalAlignment="Top" Width="62" IsDefault="True" />

此按钮(在Guest.xaml窗口中)将新的访客添加到数据库中。

GuestViewModel.cs

    private tblGuest guest;
    public tblGuest Guest    // Guest to be added into database
    {
        get
        {
            return guest;
        }
        set
        {
            guest = value;
            OnPropertyChanged("Guest");
        }
    }

    public ICommand _btnAddGuest;
    public ICommand btnAddGuest    // Command for adding new guest
    {
        get
        {
            if (_btnAddGuest == null)
            {
                _btnAddGuest = new DelegateCommand(delegate()
                {
                    try
                    {
                        Service1Client wcf = new Service1Client();
                        wcf.AddGuest(Guest);    // "AddGuest()" WCF method adds new guest to database
                        wcf.Close();
                    }
                    catch
                    {
                        Trace.WriteLine("working...", "MyApp");
                    }
                });
            }
            return _btnAddGuest;
        }
    }

如何解决这个问题呢？有什么简单的方法吗？因为我是WPF，WCF和MVVM的新手，请您能详细解释您的解决方案...

最好的祝福，
弗拉基米尔

最佳答案

只需使用GuestViewModel中与BookingsViewModel的现有连接即可。

以下建议未经测试，但您会明白的

public ICommand btnAddGuest    // Command for opening child window
    {
        get
        {
            if (_btnAddGuest == null)
            {
                _btnAddGuest = new DelegateCommand(delegate()
                {
                    try
                    {
                        Guests guest = new Guests();
                        guest.ShowDialog();

                        // Add some Logic here and an is save check property to your GuestVM
                        // sample solution
                        // var vm = guest.DataContext as GuestViewModel;
                        // if(vm != null)
                        //     if(vm.IsSaved)
                        //     {
                        //         var model = vm.Guest as tblGuest;
                        //         Guests.Add(model);                // will add him to your list
                        //         Guest = model                     // will add him at your selected Guest
                        //     }
                    }
                    catch
                    {
                        Trace.WriteLine("working...", "MyApp");
                    }
                });
            }
            return _btnAddGuest;
        }
    }

关于c# - 从其他窗口中刷新组合框列表，MVVM，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/17279110/