notification.md

This is RxJS v 4. Find the latest version here

Notification object

Represents a notification to an observer.

Usage

This can be dematerialized into an Observable.

var source = Rx.Observable
  .of(
    Rx.Notification.createOnNext(42),
    Rx.Notification.createOnCompleted()
  )
  .dematerialize();

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Next: 42
// => Completed

Location

File:

• notification.js

Notification Methods

• createOnCompleted
• createOnError
• createOnNext

Notification Instance Methods

• accept
• toObservable

Notification Properties

• error
• kind
• value

Notification Methods

Rx.Notification.createOnCompleted()

# Ⓢ

Creates an object that represents an OnCompleted notification to an observer.

Returns

Notification - The OnCompleted notification.

Example

var source = Rx.Observable
  .of(Rx.Notification.createOnCompleted() )
  .dematerialize();

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Completed

---

Rx.Notification.createOnError(exception)

# Ⓢ

Creates an object that represents an OnError notification to an observer.

Arguments

1. error: Any - The exception contained in the notification.

Returns

Notification - The OnError notification containing the exception.

Example

var source = Rx.Observable
  .of(Rx.Notification.createOnError(new Error('woops')) )
  .dematerialize();

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Error: Error: woops

Location

• rx.js

---

Rx.Notification.createOnNext(value)

# Ⓢ

Creates an object that represents an OnNext notification to an observer.

Arguments

1. value: Any - The value contained in the notification.

Returns

Notification: The onNext notification containing the value.

Example

var source = Rx.Observable
  .of(
    Rx.Notification.createOnNext(42),
    Rx.Notification.createOnCompleted()
  )
  .dematerialize();

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Next: 42
// => Completed

---

Notification Instance Methods

Rx.Notification.prototype.accept(observer | onNext, onError, onCompleted)

# Ⓢ

Invokes the delegate corresponding to the notification or the observer's method corresponding to the notification and returns the produced result or the individual functions given.

Arguments

1. [observer]: Observer Observer to invoke the notification on.

OR

1. onNext: Function - Function to invoke for an onNext notification.
2. onError: Function - Function to invoke for an onError notification.
3. onCompleted: Function - Function to invoke for an onCompleted notification.

Returns

Any: Result produced by the observation.

Example

/* Using an observer */
var observer = Rx.Observer.create(function (x) { return x; });

var notification = Rx.Notification.createOnNext(42);

console.log(notification.accept(observer));

// => 42

/* Using a function */
var notification = Rx.Notification.createOnNext(42);

console.log(notification.accept(function (x) { return x; }))
// => 42

---

Rx.Notification.prototype.toObservable([scheduler])

# Ⓢ

Returns an observable sequence with a single notification.

Arguments

1. [scheduler = Rx.Scheduler.immediate] Scheduler: Scheduler to send out the notification calls on.

Returns

Observable: The observable sequence that surfaces the behavior of the notification upon subscription.

Example

/* Without a scheduler */
var source = Rx.Notification.createOnNext(42)
  .toObservable();

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Next: 42
// => Completed

/* With a scheduler */
var source = Rx.Notification.createOnError(new Error('error!'))
  .toObservable(Rx.Scheduler.default);

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Error: Error: error!

---

Notification Properties

error

# Ⓢ

Gets the exception from the OnError notification.

Returns

Any: The Error from the onError notification.

Example

var notification = Rx.Notification.createOnError(new Error('invalid'));
console.log(notification.error);

// => Error: invalid

---

kind

# Ⓢ

Gets the kind from the notification which denotes 'N' for OnNext, 'E' for OnError and 'C' for OnCompleted.

Returns

String: The kind from the notification which denotes 'N' for OnNext, 'E' for OnError and 'C' for OnCompleted.

Example

var notification = Rx.Notification.createOnCompleted();
console.log(notification.kind);

// => C

---

value

# Ⓢ

Gets the value from the onNext notification.

Returns

Any: The value from the onNext notification.

Example

var notification = Rx.Notification.createOnNext(42);
console.log(notification.value);

// => 42

---