public void MakeAnnouncement(string message, bool polite = false)
{
#if NET47
string previousAccessibleLabel = Label;
var announcementResetTimer = new DispatcherTimer();
announcementResetTimer.Interval = new TimeSpan(0, 0, 5);
announcementResetTimer.Tick += (sender, args) => {
element?.Dispatcher.BeginInvoke((Action)(() => {
AutomationProperties.SetLiveSetting(element, AutomationLiveSetting.Off);
Label = previousAccessibleLabel;
}), DispatcherPriority.Normal);
announcementResetTimer.Stop();
};
element.Dispatcher.BeginInvoke((Action)(() => {
AutomationProperties.SetLiveSetting(element, polite ? AutomationLiveSetting.Polite : AutomationLiveSetting.Assertive);
Label = message;
var peer = FrameworkElementAutomationPeer.FromElement(element);
if (peer != null)
{
peer.RaiseAutomationEvent(AutomationEvents.LiveRegionChanged);
// HACK: Giving some time to announce the message
announcementResetTimer.Start();
}
}), DispatcherPriority.Normal);
#else
return;
#endif
}
public void SetAccessibilityLiveRegion(TFrameworkElement view, string liveRegion)
{
var liveSetting = AutomationLiveSetting.Off;
switch (liveRegion)
{
case "polite":
liveSetting = AutomationLiveSetting.Polite;
break;
case "assertive":
liveSetting = AutomationLiveSetting.Assertive;
break;
}
AutomationProperties.SetLiveSetting(view, liveSetting);
}