Module ringo/events
Exports an EventEmitter classes that provide methods to emit events and register event listener functions.
Class EventEmitter
Instance Methods
- emit(type, [args...])
- listeners(type)
- on(type, listener)
- removeAllListeners(type)
- removeListener(type, listener)
Class JavaEventEmitter
Instance Methods
- addListener(type, listener)
- addSyncListener(type, listener)
- emit(type, [args...])
- on(type, listener)
- removeAllListeners(type)
- removeListener(type, listener)
Instance Properties
EventEmitter ()
This class provides methods to emit events and add or remove event listeners.
The EventEmitter function can be used as constructor or as mix-in. Use the
new keyword to construct a new EventEmitter:
const emitter = new EventEmitter();
To add event handling methods to an existing object, call or apply the
EventEmitter function with the object as this:
EventEmitter.call(object);
EventEmitter.prototype. emit (type, [args...])
Emit an event to all listeners registered for this event type
Parameters
| String | type | type the event type |
| ... | [args...] | optional arguments to pass to the listeners |
Returns
true if the event was handled by at least one listener, false otherwise |
Throws
EventEmitter.prototype. listeners (type)
Get an array containing the listener functions for the given event. If no listeners exist for the given event a new array is created. Changes on the return value will be reflected in the EventEmitter instance.
Parameters
| String | type | the event type |
Returns
| Array | the lister array |
EventEmitter.prototype. on (type, listener)
Add a listener function for the given event. This is a shortcut for addListener()
Parameters
| String | type | the event type |
| Function | listener | the listener |
Returns
| EventEmitter | this object for chaining |
EventEmitter.prototype. removeAllListeners (type)
Remove all listener function for the given event.
Parameters
| String | type | the event type |
Returns
| EventEmitter | this object for chaining |
EventEmitter.prototype. removeListener (type, listener)
Remove a listener function for the given event.
Parameters
| String | type | the event type |
| Function | listener | the listener |
Returns
| EventEmitter | this object for chaining |
JavaEventEmitter (classOrInterface, eventMapping)
An adapter for dispatching Java events to Ringo. This class takes a Java class or interface as argument and creates a Java object that extends or implements the class or interface and forwards method calls to event listener functions registered using the EventEmitter methods.
Like EventEmitter, JavaEventEmitter can be used as
constructor or as mix-in. Use the new keyword to construct a new
JavaEventEmitter:
const emitter = new JavaEventEmitter(JavaClassOrInterface);
To add event handling methods to an existing object, call or apply the
JavaEventEmitter function with the object as this:
JavaEventEmitter.call(object, JavaClassOrInterface);
JavaEventEmitter accepts an object as optional second argument that maps
Java methods to event names. If the first argument is a Java class
this mapping also allows to select which methods should be overridden. If
called without event mapping the method name is used as event name, except
for methods like onFoo which will trigger event foo.
Parameters
| java.lang.Class|Array | classOrInterface | a Java class or interface, or an Array containing multiple Java interfaces. |
| Object | eventMapping | optional object mapping method names to event names. If this parameter is defined only methods whose name is a property key in the object will be overridden, and the event type will be set to the property value instead of the method name. |
JavaEventEmitter.prototype. addListener (type, listener)
Add a listener function for the given event. The function will be called asynchronously on the thread of the local event loop.
Parameters
| String | type | the event type |
| Function | listener | the listener |
JavaEventEmitter.prototype. addSyncListener (type, listener)
Add a synchronous listener function for the given event. A synchronous listener will be called by an outside thread instead of the thread of the local event loop. This means it can be called concurrently while this worker is running other code.
Parameters
| String | type | the event type |
| Function | listener | the listener |
JavaEventEmitter.prototype. emit (type, [args...])
Emit an event to all listeners registered for this event type
Parameters
| String | type | type the event type |
| ... | [args...] | optional arguments to pass to the listeners |
Returns
true if the event was handled by at least one listener, false otherwise |
Throws
JavaEventEmitter.prototype. impl
The generated Java object. This implements the Java interface
passed to the JavaEventEmitter constructor and can be passed
to Java code that expects given interface.
JavaEventEmitter.prototype. on (type, listener)
Add a listener function for the given event. This is a shortcut for addListener()
Parameters
| String | type | the event type |
| Function | listener | the listener |
JavaEventEmitter.prototype. removeAllListeners (type)
Removes all listener functions for a given event.
Parameters
| String | type | the event type |
JavaEventEmitter.prototype. removeListener (type, listener)
Remove a listener function for the given event.
Parameters
| String | type | the event type |
| Function | listener | the listener |