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WPF Combobox Bind FallbackValue to Property

Posted By:      Posted Date: September 17, 2010    Points: 0   Category :WPF
What I am wanting to do seems fairly simple, but WPF doesn't seem to like it. Basically I am binding a ComboBox's SelectedValue to my object:       <ComboBox SelectedValue="{Binding SendToBinLocation}" Name="cboToBin" Width="100" DisplayMemberPath="BinLocation" SelectedValuePath="BinLocation" ItemsSource="{Binding ToBinList, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}}" BorderBrush="{Binding Path=SendToBinLocation, Converter={StaticResource MissingBinConverter}, Mode=OneWay}"> <ComboBox.ItemTemplate> <DataTemplate> <TextBlock FontSize="16" Text="{Binding BinLocation}"/> </DataTemplate> </ComboBox.ItemTemplate> </ComboBox>  This works fine. However, I am wanting to specify a default value for the combobox in the event ToBinLocation is empty or null. I can achieve this by hard-coding in FallBackValue=somevalue, but this is not what I want to do. What I would like to do is bind the FallBackValue to another property of the object. You can't databind to fallBackValue because it is a dependency property, so how would I go about specifying the FallBackValue with another property on the object? The idea here is that if the SendToBinLocation is null or empty, the Comboxvalu

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