Question

all,

I am really stuck on a very basic concept – I just cannot find an answer that I really understand.

I have a view – viewContacts. Its datacontext is a viewmodel – viewmodelContacts.

On the view I have a combobox for ‘titles’ (you know … Mr, Mrs, Miss, etc). I want to bind the itemssource so it shows a list of options, and bind the SelectedValue so that it stores the key in the viewmodelContacts TitleId property.

The ‘source’ list if titles (that I want to bind ItemsSource to) is actually in a separate static class – note NOT the viewmodel!

internal static class Titles
{
    static IList<Title> _colTitles = null;
    static Titles()
    {
        _colTitles = new List<Title>();
        _colTitles.Add(new Title() { TitleId = 1, Description = "Mr." });
        _colTitles.Add(new Title() { TitleId = 2, Description = "Mrs." });
        _colTitles.Add(new Title() { TitleId = 3, Description = "Miss." });
        _colTitles.Add(new Title() { TitleId = 4, Description = "Ms." });
    }

    internal static IList<Title> GetTitles()
    {
        return _colTitles;
    }
}

(later on, of course, this stuff will be fetched from a database).

This simple task exceeds my talent as a WPF developer.

How do I set the ItemsSource to this static class? How do I further set the DisplayMemberPath to the Description property of the underlying Title object?

What do I set the SelectedValue and SelectedValuePath to?

Really hoping someone can help me out with what appears to be a simple problem that I just cannot work out.

Thanks,
Gray

Answer 1

In your viewModel create a property like so:

public IList<Title> VmTitles
{
    get
    {
        return Titles.GetTitles();
    }
}

private Title _selectedTitle;
public Title SelectedTitle
{
    get
    {
        return _selectedTitle;
    }
    set
    {
        if (value != _selectedTitle)
        {
            _selectedTitle = value;
            OnPropertyChanged("SelectedTitle");
        }
    }
}

Then in your .xaml you do this:

<ComboBox x:Name="cboTitle" ItemsSource="{Binding Path=VmTitles}" DisplayMemberPath="Description" SelectedItem="{Binding Path=SelectedTitle}" />