How to create ListBoxItem within behind code

Question

Hi there,

For some reason I have to initialize the ListBox items in behind code, the reason is too complication to tell.

The LoadFamily() is called during WPF UserControl show up.

public void LoadFamily()
{
    DataTemplate listItemTemplate = this.FindResource("ManDataTemplate") as DataTemplate;

    foreach (Person man in family)
    {
        ListBoxItem item = new ListBoxItem();

        item.DataContext = man;
        item.ContentTemplate = listItemTemplate;
        // other initialize for item object
        this.ActivityList.Items.Add(item);
    }
}

In my xmal file, I define a DataTemplate.

<DataTemplate x:Key="ManDataTemplate" DataType="{x:Type local:Person}">
    <TextBlock Text="{Binding Path=Name}"/>
</DataTemplate>

But the ListBox only contains empty text block, the person's Name doesn't not display. I don't know why, maybe the data binding is wrong, but how to do it in behind code.

Thanks for your any help! (WPF 3.5 or 4.0)

/////////////////////////////////////////////////////////////

Thanks for all your help. I found where I was wrong. I should not add ListBoxItem into ActivityList.Items, one is UIElement, the other is >DataCollection. They are two different thing.

I should modify the code as follow:

foreach (Person man in family)
{
    this.ActivityList.Items.Add(man);
    ListBoxItem item = this.ActivityList.ItemContainerGenerator.ContainerFromItem(man) as ListBoxItem;
    item.ContentTemplate = listItemTemplate;
    // other initialize for item object
}

Answer 1

I don't see the benefit of creating the listboxitems manually. Just set the ItemsSource of the Listbox to the list of person (family).

Answer 2

You need to just set the ItemTemplate of your ListBox not the ContentTemplate of each control

as below

public partial class Window1 : Window { List family = new List(); public Window1() { family.Add(new Person() { Name = "Saurabh" }); family.Add(new Person() { Name = "Sumit" }); family.Add(new Person() { Name = "XYZ" });

        InitializeComponent();

       // ActivityList.ItemContainerGenerator.ItemsChanged += new System.Windows.Controls.Primitives.ItemsChangedEventHandler(ItemContainerGenerator_ItemsChanged);

        LoadListBox();


    }

    public void LoadListBox()
    {
        DataTemplate listItemTemplate = this.FindResource("ManDataTemplate") as DataTemplate;
        ActivityList.ItemTemplate = listItemTemplate;
        foreach (Person man in family)
        {
            ListBoxItem item = new ListBoxItem();

            //item.DataContext = man;

            // item.ContentTemplate = listItemTemplate;

            // other initialize for item object 
            ActivityList.Items.Add(man);
            //listItemTemplate.LoadContent();

        }





    }


}

public class Person
{
    public string Name { get; set; }


}

Answer 3

There could be binding error. That's the reason why the textblock is empty. Check the Output window of VisualStudio, it will display the binding errors if exist.

HTH