Events are notices broadcast when some change or action occurs involving an object. Listeners define functions that execute when specific events occur. Classes can define and trigger events. MATLAB® can trigger predefined events when code accesses object properties.
Events and Listeners
- Overview Events and Listeners
Use events and listeners to send and respond to messages.
- Event and Listener Concepts
Events broadcast notifications to all registered listener and pass event-specific data to listener callback functions.
- Events and Listeners Syntax
These code examples show how to define events and listeners.
- Event Access List
Specify a list of classes that can be notified of a specific event.
- Event Attributes
Control access to events by setting event attributes.
- Listener Callback Syntax
Specify listener callbacks using function handles.
- Callback Execution
Errors in listener callbacks do not prevent execution of other listeners. However, the order of listener execution is not defined.
- Listener Lifecycle
MATLAB manages the lifecycle of listeners. For greater control of listener lifecycle, constructor listener objects using the
listenermethod instead of
- Determine If Event Has Listeners
You can determine if there are listeners defined for a specific event and event source.
Samples of Events and Listeners
- Define Custom Event Data
Redefine the event data that MATLAB passes to listeners when an event is triggered.
- Observe Changes to Property Values
Listeners can respond to changes in the value of properties using predefined property events.
- Implement Property Set Listener
Listeners can respond to changes in property values before or after MATLAB assigns the value.
- Techniques for Using Events and Listeners
This example shows how to enable and disable listener execution using context menus.
- Restore Listeners
You can restore property listeners from the