(WPF) Binding two classes to a control

Question

I have two viewmodels. One which displays a collection of IPAddresses, and one which displays a collection of objects that has numerous parameters. One of these parameters is an IPAddress. So, I have another panel that binds to the properties of the second object. I would like a combobox to have the ItemSource set to the first object, but the selected item bound to the second object. However, I can only seem to set one datacontext on a control in code behind. Is there any way around this? I would prefer to do this all in code behind if possible (i find the xaml programming to be non-ideal at best), but I'll take anything.

Answer 1

This would be easier to answer if I had a better description of your objects including names. But it sounds to me like you should make a dictionary with the ipaddress as the key and the second object as the value.

If you can do that then you can bind to it in code like so:

comboBox.ItemsSource = dictionary;
comboBox.DisplayMemberPath = "Key";
comboBox.SelectedValuePath = "Value";

This is assuming that you have exactly one "second object" for every IPAddress in the collection. Which sounds about right given your description.

Answer 2

For the ComboBox bind the collection of IPAddresses to the ItemsSource property, and bind the SelectedItem of the ComboBox to the IPAddress property of the SelectedItem of the collection of "numerous property objects".

Answer 3

Take a look at the Source property of Bindings. It is basically a DataContext for a specific binding. It should make what you're trying to do very simple, especially in code behind.