Can't get value in MultiBindingBehavior

[sun8134]

I used MultiBindingBehavior in wp7.5, the xaml is here:

            <ListBox Height="510" Name="lb1">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Width="432" Orientation="Horizontal">
                            <TextBlock TextWrapping="Wrap" Text="{Binding name}" FontSize="32" Width="200" x:Name="t12" />
                            <TextBlock TextWrapping="Wrap" Text="{Binding number,Mode=TwoWay}" FontSize="32" Margin="0" x:Name="t11" DataContext="{Binding}">
                                    <i:Interaction.Behaviors>
                                        <cimbalinoBehaviors:MultiBindingBehavior Converter="{StaticResource ColorConverter}" PropertyName="Foreground" >
                                            <cimbalinoBehaviors:MultiBindingItem Value="{Binding name}" />
                                            <cimbalinoBehaviors:MultiBindingItem Value="{Binding ElementName=listpicker1, Path=SelectedItem.Content}" />                                                
                                        </cimbalinoBehaviors:MultiBindingBehavior>
                                    </i:Interaction.Behaviors>
                            </TextBlock>
                        </StackPanel>
                    </DataTemplate>
                </ListBox.ItemTemplate>                 
            </ListBox>

but in "public override object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)", the values[0] is null...

how can I get the value in databinding?

Thinks

[pedrolamas]

I assume "name" is a property from your ViewModel, correct? Is it really "name" or should it be "Name"? Take a look in the Output window in Visual Studio and check if there is an Binding error message that may explain why the value is null.

[sun8134]

yes the "name" is a property of my ViewModel

And I found that in each binding,the "public override object Convert" method will run twice the first time the values[0] is null and the second time it will have the correct value

[pedrolamas]

That is actually expected behavior, as PropertyChanged events get raised each time a property value changes.

In this case, if the MultiBindingBehavior contains 2 bindings, it will raise the Convert() method twice once per each PropertyChanged event, and at startup, I guess a PropertyChanged event is raised for each of the binded properties.