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IViewAutomationPeer Interface

Allows a customized view of a ListView that derives from ViewBase to implement automation peer features that are specific to the custom view.

Namespace:  System.Windows.Automation.Peers
Assembly:  PresentationFramework (in PresentationFramework.dll)
public interface IViewAutomationPeer
Interfaces cannot be used directly in XAML; see types that implement this interface.

The following code shows a custom view implementing IViewAutomationPeer in a separate class to handle a button that appears at the top of the ListView control.

public class OneButtonHeaderView : ViewBase
{
    protected override IViewAutomationPeer GetAutomationPeer(ListView parent)
    {
        return new OneButtonHeaderViewAutomationPeer( this, parent );
    }


...


public class OneButtonHeaderViewAutomationPeer : IViewAutomationPeer
{
    ListView m_lv;

    public OneButtonHeaderViewAutomationPeer(OneButtonHeaderView control, ListView parent)
    {
        m_lv = parent;
    }

    ItemAutomationPeer IViewAutomationPeer.CreateItemAutomationPeer(Object item)
    {
        ListViewAutomationPeer lvAP = UIElementAutomationPeer.FromElement(m_lv) as ListViewAutomationPeer;
        return new ListBoxItemAutomationPeer(item, lvAP);
    }

    AutomationControlType IViewAutomationPeer.GetAutomationControlType()
    {
        return AutomationControlType.List;
    }

    List<AutomationPeer> IViewAutomationPeer.GetChildren(List<AutomationPeer> children)
    {
        // the children parameter is a list of automation peers for all the known items
        // our view must add its banner button peer to this list.

        Button b = (Button)m_lv.Template.FindName("BannerButton", m_lv);
        AutomationPeer peer = UIElementAutomationPeer.CreatePeerForElement(b);

        //If children is null, we still need to create an empty list to insert the button
        if (children == null)
        {
            children = new List<AutomationPeer>();
        }

        children.Insert(0, peer);

        return children;
    }

    Object IViewAutomationPeer.GetPattern(PatternInterface patternInterface)
    {
        // we can invoke the banner button 
        if (patternInterface == PatternInterface.Invoke)
        {
            Button b = (Button)m_lv.Template.FindName("BannerButton", m_lv);
            AutomationPeer peer = UIElementAutomationPeer.FromElement(b);
            if (peer != null)
                return peer;
        }

        // if this view does not have special handling for the pattern interface, return null
        // the ListViewAutomationPeer.GetPattern default handling will be used.
        return null;
    }

    void IViewAutomationPeer.ItemsChanged(System.Collections.Specialized.NotifyCollectionChangedEventArgs e) { }

    void IViewAutomationPeer.ViewDetached() { }
}

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0
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