Hi Dario,
Thanks for using Syncfusion products.
As you have updated, display text of the appointments can be customized through ParseDisplayItem event. But since as the customization in the event has to be notified, the e.Handled must be enabled and also the event must be subscribed before initializing appointment providers to the ScheduleControl. Please make use of the below code,
Code Example
//Event subscription.
this.scheduleControl1.ParseDisplayItem += new ParseDisplayItemEventHandler(scheduleControl1_ParseDisplayItem);
void scheduleControl1_ParseDisplayItem(object sender, ParseDisplayItemEventArgs e)
{
e.FormattedText = string.Format("{0} ", e.Item.Subject);
e.FormattedText += "Custom Text";
//Handled must be true to change the formatted text.
e.Handled = true;
}
Sample Link
Please let us know, if we have misunderstood your query.
Regards,
Amal Raj U.