Update listener handling

marcelwgn · marcelwgn · commit 5716df913b07 · 2020-10-28T11:06:06.000+01:00
diff --git a/Microsoft.Toolkit.Uwp.UI.Controls/RadialGauge/RadialGauge.cs b/Microsoft.Toolkit.Uwp.UI.Controls/RadialGauge/RadialGauge.cs
@@ -469,9 +469,10 @@ protected override void OnValueChanged(double oldValue, double newValue)
         {
             OnValueChanged(this);
             base.OnValueChanged(oldValue, newValue);
-            if (FrameworkElementAutomationPeer.CreatePeerForElement(this) is RadialGaugeAutomationPeer peer)
+            if (AutomationPeer.ListenerExists(AutomationEvents.LiveRegionChanged))
             {
-                peer.RaiseValueChangedEvent(oldValue, newValue);
+                var peer = FrameworkElementAutomationPeer.FromElement(this) as RadialGaugeAutomationPeer;
+                peer?.RaiseValueChangedEvent(oldValue, newValue);
             }
         }
 

Original file line number	Diff line number	Diff line change
`@@ -469,9 +469,10 @@ protected override void OnValueChanged(double oldValue, double newValue)`
`469`	`469`	`{`
`470`	`470`	`OnValueChanged(this);`
`471`	`471`	`base.OnValueChanged(oldValue, newValue);`
`472`		`- if (FrameworkElementAutomationPeer.CreatePeerForElement(this) is RadialGaugeAutomationPeer peer)`
	`472`	`+ if (AutomationPeer.ListenerExists(AutomationEvents.LiveRegionChanged))`
`473`	`473`	`{`
`474`		`- peer.RaiseValueChangedEvent(oldValue, newValue);`
	`474`	`+ var peer = FrameworkElementAutomationPeer.FromElement(this) as RadialGaugeAutomationPeer;`
	`475`	`+ peer?.RaiseValueChangedEvent(oldValue, newValue);`
`475`	`476`	`}`
`476`	`477`	`}`
`477`	`478`