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Defined in: data/observable/index.ts

Observable is used when you want to be notified when a change occurs. Use on/off methods to add/remove listener. Please note that should you be using the new Observable({}) constructor, it is obsolete since v3.0, and you have to migrate to the "data/observable" fromObject({}) or the fromObjectRecursive({}) functions.

Extended by ​

Constructors ​

Constructor ​

ts
new Observable(): Observable;

Returns ​

Observable

Properties ​

propertyChangeEvent ​

ts
static propertyChangeEvent: string;

Defined in: data/observable/index.ts

String value used when hooking to propertyChange event.

Ns Event ​

propertyChange

Methods ​

_createPropertyChangeData() ​

ts
_createPropertyChangeData(
   propertyName: string, 
   value: any, 
   oldValue?: any): PropertyChangeData;

Defined in: data/observable/index.ts

This method is intended to be overriden by inheritors to provide additional implementation.

Parameters ​

ParameterType
propertyNamestring
valueany
oldValue?any

Returns ​

PropertyChangeData

_emit() ​

ts
_emit(eventName: string): void;

Defined in: data/observable/index.ts

Parameters ​

ParameterType
eventNamestring

Returns ​

void

addEventListener() ​

ts
addEventListener(
   eventName: string, 
   callback: (data: EventData) => void, 
   thisArg?: any, 
   once?: boolean): void;

Defined in: data/observable/index.ts

Adds a listener for the specified event name.

Parameters ​

ParameterTypeDescription
eventNamestringName of the event to attach to.
callback(data: EventData) => voidA function to be called when some of the specified event(s) is raised.
thisArg?anyAn optional parameter which when set will be used as "this" in callback method call.
once?booleanAn optional parameter which when set will cause the event listener to fire once.

Returns ​

void

get() ​

ts
get(name: string): any;

Defined in: data/observable/index.ts

Gets the value of the specified property.

Parameters ​

ParameterType
namestring

Returns ​

any

hasListeners() ​

ts
hasListeners(eventName: string): boolean;

Defined in: data/observable/index.ts

Checks whether a listener is registered for the specified event name.

Parameters ​

ParameterTypeDescription
eventNamestringThe name of the event to check for.

Returns ​

boolean

notify() ​

ts
notify<T>(data: T): void;

Defined in: data/observable/index.ts

Notify this Observable instance with some data. This causes all event handlers on the Observable instance to be called, as well as any 'global' event handlers set on the instance's class.

Type Parameters ​

Type Parameter
T extends Optional<EventData, "object">

Parameters ​

ParameterTypeDescription
dataTan object that satisfies the EventData interface, though with an optional 'object' property. If left undefined, the 'object' property will implicitly be set as this Observable instance.

Returns ​

void

notifyPropertyChange() ​

ts
notifyPropertyChange(
   name: string, 
   value: any, 
   oldValue?: any): void;

Defined in: data/observable/index.ts

Notifies all the registered listeners for the property change event.

Parameters ​

ParameterType
namestring
valueany
oldValue?any

Returns ​

void

off() ​

ts
off(
   eventName: string, 
   callback?: (data: EventData) => void, 
   thisArg?: any): void;

Defined in: data/observable/index.ts

Removes the listener(s) for the specified event name.

Parameters ​

ParameterTypeDescription
eventNamestringThe name of the event.
callback?(data: EventData) => voidAn optional specific event listener to remove (if omitted, all event listeners by this name will be removed).
thisArg?anyAn optional parameter which, when set, will be used to refine search of the correct event listener to be removed.

Returns ​

void

on() ​

ts
on(
   eventName: string, 
   callback: (data: EventData) => void, 
   thisArg?: any): void;

Defined in: data/observable/index.ts

Adds a listener for the specified event name.

Parameters ​

ParameterTypeDescription
eventNamestringThe name of the event.
callback(data: EventData) => voidThe event listener to add. Will be called when an event of the given name is raised.
thisArg?anyAn optional parameter which, when set, will be bound as the this context when the callback is called. Falsy values will be not be bound.

Returns ​

void

once() ​

ts
once(
   eventName: string, 
   callback: (data: EventData) => void, 
   thisArg?: any): void;

Defined in: data/observable/index.ts

Adds a listener for the specified event name, which, once fired, will remove itself.

Parameters ​

ParameterTypeDescription
eventNamestringThe name of the event.
callback(data: EventData) => voidThe event listener to add. Will be called when an event of the given name is raised.
thisArg?anyAn optional parameter which, when set, will be bound as the this context when the callback is called. Falsy values will be not be bound.

Returns ​

void

removeEventListener() ​

ts
removeEventListener(
   eventName: string, 
   callback?: (data: EventData) => void, 
   thisArg?: any): void;

Defined in: data/observable/index.ts

Removes listener(s) for the specified event name.

Parameters ​

ParameterTypeDescription
eventNamestringName of the event to attach to.
callback?(data: EventData) => voidAn optional parameter pointing to a specific listener. If not defined, all listeners for the event names will be removed.
thisArg?anyAn optional parameter which when set will be used to refine search of the correct callback which will be removed as event listener.

Returns ​

void

set() ​

ts
set(name: string, value: any): void;

Defined in: data/observable/index.ts

Updates the specified property with the provided value.

Parameters ​

ParameterType
namestring
valueany

Returns ​

void

setProperty() ​

ts
setProperty(name: string, value: any): void;

Defined in: data/observable/index.ts

Updates the specified property with the provided value and raises a property change event and a specific change event based on the property name.

Parameters ​

ParameterType
namestring
valueany

Returns ​

void

addEventListener() ​

ts
static addEventListener(
   eventName: string, 
   callback: (data: EventData) => void, 
   thisArg?: any, 
   once?: boolean): void;

Defined in: data/observable/index.ts

Please avoid using the static event-handling APIs as they will be removed in future.

Parameters ​

ParameterType
eventNamestring
callback(data: EventData) => void
thisArg?any
once?boolean

Returns ​

void

Deprecated ​

off() ​

ts
static off(
   eventName: string, 
   callback?: (data: EventData) => void, 
   thisArg?: any): void;

Defined in: data/observable/index.ts

Please avoid using the static event-handling APIs as they will be removed in future.

Parameters ​

ParameterType
eventNamestring
callback?(data: EventData) => void
thisArg?any

Returns ​

void

Deprecated ​

on() ​

ts
static on(
   eventName: string, 
   callback: (data: EventData) => void, 
   thisArg?: any, 
   once?: boolean): void;

Defined in: data/observable/index.ts

Please avoid using the static event-handling APIs as they will be removed in future.

Parameters ​

ParameterType
eventNamestring
callback(data: EventData) => void
thisArg?any
once?boolean

Returns ​

void

Deprecated ​

once() ​

ts
static once(
   eventName: string, 
   callback: (data: EventData) => void, 
   thisArg?: any): void;

Defined in: data/observable/index.ts

Please avoid using the static event-handling APIs as they will be removed in future.

Parameters ​

ParameterType
eventNamestring
callback(data: EventData) => void
thisArg?any

Returns ​

void

Deprecated ​

removeEventListener() ​

ts
static removeEventListener(
   eventName: string, 
   callback?: (data: EventData) => void, 
   thisArg?: any): void;

Defined in: data/observable/index.ts

Please avoid using the static event-handling APIs as they will be removed in future.

Parameters ​

ParameterType
eventNamestring
callback?(data: EventData) => void
thisArg?any

Returns ​

void

Deprecated ​

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