/// <summary>
/// Returns true if in <paramref name="elementPeer"/> parents chain there is an UIElement with
/// ImportantForAccessibility value of Yes or NoHideDescendants or (Auto and AccessibilityLabelAttached attached property is set).
/// 'Yes' or (Auto and AccessibilityLabelAttached attached property is set) denotes that the element is visible
/// to the narrator as a container i.e. its children are 'hidden'. 'NoHideDescendants' denotes that both
/// the element and its children are 'hidden'. 'Hidden' children have AccessibilityView set to 'Raw'.
/// </summary>
/// <param name="elementPeer"></param>
/// <returns></returns>
private static bool IsHiddenByAncestor(AutomationPeer elementPeer)
{
if (elementPeer == null)
{
return(false);
}
bool result;
switch (elementPeer.Navigate(AutomationNavigationDirection.Parent))
{
case FrameworkElementAutomationPeer parentFEAutomationPeer:
if (parentFEAutomationPeer.Owner != null)
{
if (DoesHideDescendants(parentFEAutomationPeer.Owner))
{
return(true);
}
}
result = IsHiddenByAncestor(parentFEAutomationPeer);
break;
case ItemAutomationPeer parentIAutomationPeer:
if (parentIAutomationPeer.Item is UIElement parentUIElement)
{
if (DoesHideDescendants(parentUIElement))
{
return(true);
}
}
result = IsHiddenByAncestor(parentIAutomationPeer);
break;
case AutomationPeer parentAutomationPeer:
result = IsHiddenByAncestor(parentAutomationPeer);
break;
case null:
result = false;
break;
default:
result = false;
break;
}
return(result);
}
internal override void Invoke()
{
var peer = FrameworkElementAutomationPeer.FromElement(TargetElement);
var comboBoxItemAutomationPeer = peer as ComboBoxItemAutomationPeer;
var comboBoxItem = (ComboBoxItem)comboBoxItemAutomationPeer.Owner;
AutomationPeer ancestor = comboBoxItemAutomationPeer;
var comboBoxAutomationPeer = ancestor as ComboBoxAutomationPeer;
while (comboBoxAutomationPeer == null)
{
ancestor = ancestor.Navigate(AutomationNavigationDirection.Parent) as AutomationPeer;
comboBoxAutomationPeer = ancestor as ComboBoxAutomationPeer;
}
comboBoxItem.IsSelected = true;
comboBoxAutomationPeer.Collapse();
}
private static void ComboBoxItemAction(UIElement element)
{
var peer = FrameworkElementAutomationPeer.FromElement(element);
var comboBoxItemAutomationPeer = peer as ComboBoxItemAutomationPeer;
var comboBoxItem = (ComboBoxItem)comboBoxItemAutomationPeer.Owner;
AutomationPeer ancestor = comboBoxItemAutomationPeer;
var comboBoxAutomationPeer = ancestor as ComboBoxAutomationPeer;
while (comboBoxAutomationPeer == null)
{
ancestor = ancestor.Navigate(AutomationNavigationDirection.Parent) as AutomationPeer;
comboBoxAutomationPeer = ancestor as ComboBoxAutomationPeer;
}
comboBoxItem.IsSelected = true;
comboBoxAutomationPeer.Collapse();
}