Events — Sending and Responding

to Messages

• “Overview Events and Listeners” on page 11-2


• “Define Custom Event Data” on page 11-6


• “Observe Changes to Property Values” on page 11-9


• “Implement Property Set Listener” on page 11-11


• “Event and Listener Concepts” on page 11-14


• “Event Attributes” on page 11-19


• “Events and Listeners Syntax” on page 11-22


• “Listener Lifecycle” on page 11-28


• “Listener Callback Syntax” on page 11-30


• “Callback Execution” on page 11-34


• “Determine If Event Has Listeners” on page 11-37


• “Listen for Changes to Property Values” on page 11-40


• “Assignment When Property Value Is Unchanged” on page 11-44


• “Techniques for Using Events and Listeners” on page 11-50

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