Windows Narrator reads the names of all the controls in the window (even hidden ones)

Question

I need to make my application visually impaired friendly... and I am facing this problem: Windows Narrator reads all the controls names in the window despite that some of them are hidden.

I have another app that I used WinForms to write it, and there it works fine.

After looking in the UI Spy I saw that WinForms app is not exposing hidden controls and WPF is exposing all the controls in the window.

Can it be that it's a bug in WPF?

Answer 1

If your controls are already in the visual tree, this behavior is the normal one, because UI Automation tree based on the Visual tree. So if you want to prevent of reading unnecessary elements using screen readers, you have to load them on demand.

You can also override the OnCreateAutomationPeer method in controls that contain visible and hidden elements to return your own AutomationPeer. Then you can override the GetChildrenCore method and return modified children collection. To update automation children tree, you need to call the AutomationPeer.ResetChildrenCache() method and the AutomationPeer.RaiseAutomationEvent(AutomationEvents.StructureChanged) one.

Answer 2

I was having the same problem. Based on Alexis's answer, I wrote the code bellow. It works for me.

public class MyAutoComplete : RadAutoCompleteBox
{
    public MyAutoComplete ()
    {
     //init stuff here   
    }


    protected override AutomationPeer OnCreateAutomationPeer()
    {
        return new MyAutomationPeer(this);
    }
}

internal class MyAutomationPeer : RadAutoCompleteBoxAutomationPeer
{
    public MyAutomationPeer(FrameworkElement owner)
        : base(owner)
    {

    }
    protected override List<AutomationPeer> GetChildrenCore()
    {
        return new List<AutomationPeer>();
    }
}