Question

I am trying to create an application that tracks JobItems. In the application, the user clicks on a “New Job” button to create a JobItem. A new window (NewJobWindow) then pops up and the user must fill in information about the Job. A few of the information needed has multiple values. For instance, you can add multiple (string) Business Units within a job Item. What I’ve done is added a listbox for users to add all the business units within it. What I don’t know how to do is bind this listbox of business units so that every time I add an item in it, the Observable Collection BusinessUnits in JobItem gets added the same item when I click the submit button. I need to know how I would do this using databinding. I have already searched Google to look for similar answers but could not find any.

Edit:

This is what I have in my JobItem Class that I need to get updated every time a user is submitting multiple BusinessUnits in the NewJobWindow:

public ObservableCollection<string> BusinessUnit
    {
        get { return businessUnit; }
        set
        {
            if(!BusinessUnit.Equals(value))
            {
                businessUnit = value;
                OnPropertyChanged("BusinessUnit");
            }
        }

    }

This is what the JobWindow looks like in xaml for adding businessunits within the listbox. I created a ValidatingListBox just so I can validate that the user has inserted an item within the list box.:

<Label Grid.Column="0" Grid.Row="5">Business Unit:</Label>
        <my:ValidatingListBox Grid.Column="1" Grid.ColumnSpan="1" Grid.Row="5" Grid.RowSpan="1" x:Name="businessUnitBox" SelectionMode="Multiple" SelectionChanged="ValidatingListBox_SelectionChanged" ItemsSource="{Binding Path=BusinessUnit}" >
        <my:ValidatingListBox.ValidationListener>
                <Binding RelativeSource="{RelativeSource FindAncestor, AncestorType=Window}" Path="BusinessUnit" Mode="TwoWay">
                <Binding.ValidationRules>
                    <my:ListBoxValidationRule ValidatesOnTargetUpdated="True" ></my:ListBoxValidationRule>
                </Binding.ValidationRules>
            </Binding>
        </my:ValidatingListBox.ValidationListener>
    </my:ValidatingListBox>

Answer 1

Binding is very simple:

<ListBox ItemsSource="{Binding MyCollection}" />  

where MyCollection is a property of ObservableCollection type. You don’t need to add items to ListBox, add them to collection, data binding will do the rest.