WPF DisplayMemberProperty无法按预期在后面的代码中运行

Question

我有一个简单的ObservableCollection我要绑定在代码中的Person类。除了DisplayMemberProperty以外，其他所有东西都绑定正常，DD.DisplayMember = "Lastname"在下拉列表中选择一个项目时，仅在下拉列表的文本部分显示Null。如果我添加<Syncfusion:SfMultiColumnDropDownControl x:Name="DD" HorizontalAlignment="Left" VerticalAlignment="Top" Width="300" Margin="20"/> 可以正常工作，但是由于我需要在运行时添加控件，因此并不是全部都是下拉菜单，我需要使它作为绑定起作用。

我的XAML：

With OC
    .Add(New Person With {.Id = "1", .Lastname = "Smith"})
    .Add(New Person With {.Id = "2", .Lastname = "Jones"})
    .Add(New Person With {.Id = "3", .Lastname = "Johnson"})
End With

Dim ItemsSourceBinding As New Binding
With ItemsSourceBinding
    .Source = OC
    .Mode = BindingMode.OneWay
    .UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged
End With
BindingOperations.SetBinding(DD, SfMultiColumnDropDownControl.ItemsSourceProperty, ItemsSourceBinding)

Dim SelectedItemBinding As New Binding
With SelectedItemBinding
    .Source = Report
    .Path = New PropertyPath("MyPerson")
    .Mode = BindingMode.TwoWay
    .UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged 
End With
BindingOperations.SetBinding(DD, SfMultiColumnDropDownControl.SelectedItemProperty, SelectedItemBinding)

Dim DisplayMemberBinding As New Binding
With DisplayMemberBinding
    .Source = OC
    .Path = New PropertyPath("Lastname")
    .Mode = BindingMode.OneWay
    .UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged
End With
BindingOperations.SetBinding(DD, SfMultiColumnDropDownControl.DisplayMemberProperty, DisplayMemberBinding)

我的代码：

LinearLayout
  --> ImageButton
  --> TextView
  --> Button

Answer 1

不应该绑定DisplayMemberProperty。应该将其设置为属性的名称，即string：

DD.DisplayMemberProperty = "LastName"

如果将其绑定到源属性，则需要确保此属性返回string“姓氏”，而不是Lastname属性的 value 。