Finding control within WPF itemscontrol

deepak picture deepak · Jun 11, 2009 · Viewed 38k times · Source

Hi i have few a single textbox within the the datatemplate for itemscontrol. When i bind the itemcontrols to a observable collection i get two text boxes. But i need to do some manipulations based on each of the text boxes for which i want to find each textbox seperatly using some id.

Can anybody help on how to find a control witin the itemscontrol in WPF.

Answer

Bryce Kahle picture Bryce Kahle · Jun 12, 2009

Using the ItemContainerGenerator you can obtain the generated container for an item and traverse the visual tree downwards to find your TextBox. In the case of an ItemsControl it will be a ContentPresenter, but a ListBox will return a ListBoxItem, ListView a ListViewItem, etc.

ContentPresenter cp = itemsControl.ItemContainerGenerator.ContainerFromItem(item) as ContentPresenter;
TextBox tb = FindVisualChild<TextBox>(cp);
if (tb != null)
{
    // do something with tb
}

public static T FindVisualChild<T>(DependencyObject depObj) where T : DependencyObject
{
    if (depObj != null)
    {
        for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
        {
            DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
            if (child != null && child is T)
            {
                return (T)child;
            }

            T childItem = FindVisualChild<T>(child);
            if (childItem != null) return childItem;
        }
    }
    return null;
}

You can also obtain the container by index if you want by using

itemsControl.ItemContainerGenerator.ContainerFromIndex(0);