Imagine:

[RadOutlookBarItem1] [RadOutlookBarItem2] [RadOutlookBar] [CONTENCONTROL]

What i want to achieve is:

User selects one of the RadOutlookBarItem's. Item's tag is bound like:

Tag="{Binding SelectedControl, Mode=TwoWay}" 

MVVM Property

public string SelectedControl 
{ 
    get { return _showControl; } 
    set 
    { 
        _showControl = value; 
        OnNotifyPropertyChanged("ShowControl"); 
    } 
}

ContentControl has multiple CustomControls and Visibility of those is bound like:

   <UserControl.Resources> 
        <Converters:BoolVisibilityConverter x:Key="BoolViz"/> 
    </UserControl.Resources> 
    <Grid x:Name="LayoutRoot" Background="White"> 
        <Views:ViewDocumentSearchControl Visibility="{Binding SelectedControl, Converter={StaticResource BoolViz}, ConverterParameter='viewDocumentSearchControl'}"/> 
        <Views:ViewStartControl Visibility="{Binding SelectedControl, Converter={StaticResource BoolViz}, ConverterParameter='viewStartControl'}"/> 
    </Grid>

Converter:

public object Convert(object value, Type targetType, object parameter, CultureInfo culture) { // here comes the logic part... should return Visibility.Collapsed : Visibility.Visible based on 'object value' value

    System.Diagnostics.Debugger.Break(); 
    return Visibility.Collapsed;  
}

now, logically the object value is always set to null. So here's it comes to my question: How can i put a value into the SelectedControl Variable for the RadOutlookBarItem's Tag. I mean something like

Tag="{Binding SelectedControl, Mode=TwoWay, VALUE='i.e.ControlName'"}

So that i can decide, using the Convert Method, whether a specific Control's visibility is either set to collapsed or visible?

help's appreciated

Christian