protected override void Attached(SciterElement element) { element.Parent.OnCustomEvent((eventName, source, target, value) => { switch (eventName) { case "waiting": if (value.IsString) { element.SetHtml($"<text>{value.AsString()}</text>"); source.SetAttributeValue("waiting", "true"); } else if (value.IsBool) { source.SetAttributeValue("waiting", (string)null); element.ClearText(); } break; } }); base.Attached(element); }