ComboBox Binding to DataClass

Question

I use a custom LoginCommandData Class to initalize a LoginDialog.

Public Class LoginCommandData
  Inherits DependencyObject
  Implements ComponentModel.INotifyPropertyChanged

  Private m_Mandators As IList 
  Private m_Mandator As Common.Data.Mandator

  Public Property Mandators() As IList
    Get
      Return m_Mandators
    End Get
    Set(ByVal value As IList)
      Dim oldValue As IList = m_Mandators
      m_Mandators = value
      OnCommandDataPropertyChanged(New ComponentModel.PropertyChangedEventArgs("Mandators"))
    End Set
  End Property

  Public Property Mandator() As Vito64.Common.Data.Mandator
    Get
      Return m_Mandator
    End Get
    Set(ByVal value As Vito64.Common.Data.Mandator)
      Dim oldValue As Vito64.Common.Data.Mandator = m_Mandator
      m_Mandator = value
      If Not Equals(oldValue, m_Mandators) Then
        OnCommandDataPropertyChanged(New ComponentModel.PropertyChangedEventArgs("Mandator"))
      End If
    End Set
  End Property

 

The Login-Xaml

  <Window.Resources>
    <VFC:LoginCommandData x:Key="LoginData" Password="MyPasswordBox" />
  </Window.Resources>

  <Grid x:Name="MyGrid" DataContext="{StaticResource LoginData}">
    <Label Content="Mandant" x:Name="LabelMandant" Height="23"/>
      <ComboBox Margin="206,143,82,126" IsSynchronizedWithCurrentItem="True"
                x:Name="ComboBoxMandator"
                DisplayMemberPath="Name" SelectedValuePath="Id"
                ItemsSource="{Binding Path=Mandators}"
                SelectedValue="{Binding Path=Mandator,
                                Mode=TwoWay,
                                UpdateSourceTrigger=PropertyChanged}">
      </ComboBox>
  </Grid>

All I want is that the "Mantator" Property will be set, if it is selected in the ComboBox  
But it dosn't work.

 

 

Answer 1

I tried the following, seems to work, the selected value is shown in the textblock

<StackPanel DataContext="{Binding Source={StaticResource mydata}}">
    <ComboBox Name="cb1" SelectedValuePath="CustId" ItemsSource="{Binding Path=CustList}" DisplayMemberPath="Name"
              SelectedValue="{Binding Mode=TwoWay,UpdateSourceTrigger=PropertyChanged,Path=CustId}"></ComboBox>
    <TextBlock Text="{Binding Path=CustId}"></TextBlock>
  </StackPanel>

Answer 2

Hi Lee

Thanks for your feedback.

I think I do the same.

Can you send your sample at horstDOTkleinATvitodataDOTch?

Best regards

Horst

Answer 3

Hi Lee

Thanks a lot for your efforts!

Analysing your sample with my solution shows two differences:

1. I was thinking to the the “Id “ in the Mandator class.
   But really I try to set with that binding the Id into the Mandators class.
   Adding a Id to the Mandators Property helps!!!
   
2. I our Application the Id is a String
   And if the String is “Nothing” the binding doesn’t work L
   Initialise it to an String.Empty helps J 
    

Thanks a lot for your Help!!!!

Best regards Horst