public List <NSObject> GetAccessibilityElements()
{
if (Container == null || Element == null)
{
return(null);
}
var children = Element.Descendants();
SortedDictionary <int, List <VisualElement> > tabIndexes = null;
List <NSObject> views = new List <NSObject>();
foreach (var child in children)
{
if (!(child is VisualElement ve))
{
continue;
}
tabIndexes = ve.GetSortedTabIndexesOnParentPage(out _);
break;
}
if (tabIndexes == null)
{
return(null);
}
foreach (var idx in tabIndexes?.Keys)
{
var tabGroup = tabIndexes[idx];
foreach (var child in tabGroup)
{
if (child is Layout ||
!(
child is VisualElement ve && ve.IsTabStop &&
AutomationProperties.GetIsInAccessibleTree(ve) != false && // accessible == true
ve.GetRenderer().NativeView is ITabStop tabStop)
)
{
continue;
}
var thisControl = tabStop.TabStop;
if (thisControl == null)
{
continue;
}
if (views.Contains(thisControl))
{
break; // we've looped to the beginning
}
views.Add(thisControl);
}
}
return(views);
}
protected virtual void UpdateNativeWidget()
{
UpdateEnabled();
UpdateTabStop();
UpdateTabIndex();
UpdateAutomationId();
var isInAccessibleTree = AutomationProperties.GetIsInAccessibleTree(Element);
if (!(isInAccessibleTree.HasValue && !isInAccessibleTree.Value))
{
UpdateAutomationLabeledBy();
UpdateAutomationName();
UpdateAutomationHelpText();
}
}
void IOrderedTraversalController.UpdateTraversalOrder()
{
// traversal order wasn't added until API 22
if ((int)Forms.SdkInt < 22)
{
return;
}
// since getting and updating the traversal order is expensive, let's only do it when a screen reader is active
// note that this does NOT get auto updated when you enable TalkBack, so the page will need to be reloaded to enable this path
var am = AccessibilityManager.FromContext(Context);
if (!am.IsEnabled)
{
return;
}
SortedDictionary <int, List <ITabStopElement> > tabIndexes = null;
foreach (var child in Element.LogicalChildren)
{
if (!(child is VisualElement ve))
{
continue;
}
tabIndexes = ve.GetSortedTabIndexesOnParentPage(out _);
break;
}
if (tabIndexes == null)
{
return;
}
AView prevControl = null;
foreach (var idx in tabIndexes?.Keys)
{
var tabGroup = tabIndexes[idx];
foreach (var child in tabGroup)
{
if (child is Layout ||
!(
child is VisualElement ve && ve.IsTabStop &&
AutomationProperties.GetIsInAccessibleTree(ve) != false && // accessible == true
ve.GetRenderer()?.View is ITabStop tabStop)
)
{
continue;
}
var thisControl = tabStop.TabStop;
if (thisControl == null)
{
continue;
}
// this element should be the first thing focused after the root
if (prevControl == null)
{
thisControl.AccessibilityTraversalAfter = NoId;
}
else
{
if (thisControl != prevControl)
{
thisControl.AccessibilityTraversalAfter = prevControl.Id;
}
}
prevControl = thisControl;
}
}
}