Can someone please tell me why the following code doesn't work? I expect that when the value is set to "False" the 2nd item would be selected when the silverlight page initially loads but it doesn't work. It's always null...ie. No item selected.

            <my:RadComboBox x:Name="BooleanValue" DisplayMemberPath="Content" SelectedValue="False">
                <my:RadComboBoxItem Content="True" />
                <my:RadComboBoxItem Content="False" />
            </my:RadComboBox>

I am actually asking this question because I am having problem with databinding combobox. I thought making it simple would be easier for people to understand what I am trying to do. Here is my real case.

I have a viewModel with a property:
        public IEnumerable<Def_Company> Def_Companies
        {
            get
            {
                _vmContext.Load(_vmContext.GetDef_CompanyQuery());
                return (IEnumerable<Def_Company>)_vmContext.Def_Companies;
            }
        }

In my App.XAML I have a static resorce:
 <viewModel:DefVewModel x:Key="app_vmDef"></viewModel:DefVewModel>

IN my Company.xaml page I have a combobox with databinding:
<my:RadComboBox x:Name="cboCompany" ItemsSource="{Binding Path=Def_Companies,Source={StaticResource app_vmDef} }" DisplayMemberPath="Name" SelectedValuePath="Id"  SelectedValue="{Binding CompanyId, Mode=TwoWay}"></my:RadComboBox>

The combobbox populates properly from the static resouce but the "SelectedValue" binding doesn't work. I event tried to hard code the selected value like "SelectedValue=1" expecting the first item to be selected upon page load since the id of the first item is 1 but it's not working.

Thanks

Since your answer solved my first question I am going to close this one and open a new thread for my 2nd question. Thank you