Question

I’m new to the forum and very new to silverlight. Myself and my coworker are working on a custom application. We are building a menu system that will only display buttons if that useris in an assigned role. A new property was created to allow roles to be defined, and for testing purposes we are simply trying to assign that value, which is a string, to a textblock’s text property. Some code is attached.

This is one of the items to be added to the collection. the allowedroles property is passing the string, this can be seen via the debugger.

<MenuButton:VerticalButtonCollection x:Key='VerticalButtonsDS' d:IsDataSource='True'>  <MenuButton:VerticalButton AllowedRoles='test, test2'>  <TextBlock Text='{Binding AllowedRoles}'></TextBlock>  </MenuButton:VerticalButton>  </MenuButton:VerticalButtonCollection>  Code for the allowed roles property   Public Shared ReadOnly AllowedRolesProperty As DependencyProperty = DependencyProperty.Register('AllowedRoles', GetType(String), GetType(mButton), New PropertyMetadata(New PropertyChangedCallback(AddressOf onAllowedRolesChanged)))   Public Shared Sub onAllowedRolesChanged(ByVal d As DependencyObject, ByVal args As DependencyPropertyChangedEventArgs)       Dim sender As mButton = CType(d, mButton)      sender.AllowedRoles = CStr(args.NewValue) End Sub 

The items are displayed in a list box, there are no errors, but binding does not work. I even attempted to do the binding in the listbox’s data template. I appologize if this is confusing, I dont’ know how to post something like this in easy to understand pieces.

Thanks

Answer 1

Ended up getting this working by doing the following. One of the tricks is that you can’t use a converter on a template binding so you bind the DataContext of the object using a template binding and then use a regular binding to access that.

<UserControl.Resources>     <mt:AllowedRolesConverter x:Key='RolesConverter'></mt:AllowedRolesConverter>      <Style x:Key='VerticalButton1Style' TargetType='mt:VerticalButton'>         <Setter Property='Template'>             <Setter.Value>                 <ControlTemplate TargetType='mt:VerticalButton'>                     <Grid x:Name='RootGrid' DataContext='{TemplateBinding AllowedRoles}' Visibility='{Binding Converter={StaticResource RolesConverter}}'>                          <Border x:Name='border' BorderThickness='1'>                             <Border.BorderBrush>                                 <SolidColorBrush x:Name='borderBrush' Opacity='0' Color='Blue'/>                             </Border.BorderBrush>                             <ContentPresenter x:Name='VBContent'                                               ContentTemplate='{TemplateBinding ContentTemplate}'                                                >                              </ContentPresenter>                         </Border>                     </Grid>                 </ControlTemplate>             </Setter.Value>         </Setter>     </Style>      <mt:VerticalButtonCollection x:Key='TestCollection'>         <mt:VerticalButton AllowedRoles='Test1'                             Style='{StaticResource VerticalButton1Style}'                             Click='VerticalButton_Click'                            >             <TextBlock Text='Test Button'></TextBlock>         </mt:VerticalButton>         <mt:VerticalButton AllowedRoles='Test1'                             Style='{StaticResource VerticalButton1Style}' Click='VerticalButton_Click_1'>             <Ellipse Width='50' Height='50' Fill='Blue'></Ellipse>         </mt:VerticalButton>     </mt:VerticalButtonCollection>      <Style x:Key='ListItemStyle' TargetType='ListBoxItem'>         <Setter Property='Template'>             <Setter.Value>                 <ControlTemplate>                     <StackPanel x:Name='Root' Orientation='Horizontal'>                         <ContentPresenter Margin='5,5,5,5'/>                     </StackPanel>                 </ControlTemplate>             </Setter.Value>         </Setter>     </Style>     <Style x:Key='ListStyle' TargetType='ListBox'>         <Setter Property='ItemContainerStyle' Value='{StaticResource ListItemStyle}' />         <Setter Property='Template'>             <Setter.Value>                 <ControlTemplate TargetType='ListBox'>                     <Grid x:Name='Root'>                         <ItemsPresenter></ItemsPresenter>                     </Grid>                 </ControlTemplate>             </Setter.Value>         </Setter>     </Style> </UserControl.Resources> <Grid x:Name='LayoutRoot' Background='White'>     <ListBox Style='{StaticResource ListStyle}' ItemsSource='{StaticResource TestCollection}' /> </Grid>      Public Class VerticalButton     Inherits Button     Implements INotifyPropertyChanged      Public Property AllowedRoles() As String         Get             Return CStr(GetValue(AllowedRolesProperty))         End Get         Set(ByVal value As String)             SetValue(AllowedRolesProperty, value)         End Set     End Property      Public Shared ReadOnly AllowedRolesProperty As DependencyProperty = DependencyProperty.Register('AllowedRoles', GetType(String), GetType(VerticalButton), New PropertyMetadata(New PropertyChangedCallback(AddressOf OnAllowedRolesChanged)))      Public Shared Sub OnAllowedRolesChanged(ByVal d As DependencyObject, ByVal args As DependencyPropertyChangedEventArgs)         Dim sender As VerticalButton = CType(d, VerticalButton)         sender.AllowedRoles = CStr(args.NewValue)     End Sub      Public Event PropertyChanged(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs) Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged End Class  Public Class VerticalButtonCollection     Inherits ObservableCollection(Of VerticalButton)  End Class