Don't set IsAccessibilityElement for everything (#13423)

* Don't set IsAccessibilityElement for everything

* - don't set IsInAccessibleTreeProperty

Author: PureWeen

Xamarin.Forms.Platform.iOS/Extensions/AccessibilityExtensions.cs

@@ -88,9 +88,24 @@ public static string SetAccessibilityLabel(this UIBarItem Control, Element Eleme
 			if (Element == null || Control == null)
 				return _defaultIsAccessibilityElement;
 
+			// If the user hasn't set IsInAccessibleTree then just don't do anything
+			if (!Element.IsSet(AutomationProperties.IsInAccessibleTreeProperty))
+				return null;
+
 #if __MOBILE__
 			if (!_defaultIsAccessibilityElement.HasValue)
-				_defaultIsAccessibilityElement = Control.IsAccessibilityElement;
+			{
+				// iOS sets the default value for IsAccessibilityElement late in the layout cycle
+				// But if we set it to false ourselves then that causes it to act like it's false
+
+				// from the docs:
+				// https://developer.apple.com/documentation/objectivec/nsobject/1615141-isaccessibilityelement
+				// The default value for this property is false unless the receiver is a standard UIKit control,
+				// in which case the value is true.
+				//
+				// So we just base the default on that logic				
+				_defaultIsAccessibilityElement = Control.IsAccessibilityElement || Control is UIControl;
+			}
 
 			Control.IsAccessibilityElement = (bool)((bool?)Element.GetValue(AutomationProperties.IsInAccessibleTreeProperty) ?? _defaultIsAccessibilityElement);
 #else

Xamarin.Forms.Platform.iOS/ViewRenderer.cs

@@ -223,12 +223,6 @@ protected void SetNativeControl(TNativeView uiview)
 			_controlChanging?.Invoke(this, EventArgs.Empty);
 #if __MOBILE__
 			_defaultColor = uiview.BackgroundColor;
-
-			// UIKit UIViews created via storyboard default IsAccessibilityElement to true, BUT
-			// UIViews created programmatically default IsAccessibilityElement to false.
-			// We need to default to true to allow all elements to be accessible by default and
-			// allow users to override this later via AutomationProperties.IsInAccessibleTree
-			uiview.IsAccessibilityElement = true;
 #else
 			uiview.WantsLayer = true;
 			_defaultColor = uiview.Layer.BackgroundColor;