Class ArrayProxy

public
import ArrayProxy from '@ember/array/proxy';

An ArrayProxy wraps any other object that implements Array and/or MutableArray, forwarding all requests. This makes it very useful for a number of binding use cases or other cases where being able to swap out the underlying array is useful.

A simple example of usage:

import { A } from '@ember/array';
import ArrayProxy from '@ember/array/proxy';

let pets = ['dog', 'cat', 'fish'];
let ap = ArrayProxy.create({ content: A(pets) });

ap.get('firstObject');                        // 'dog'
ap.set('content', ['amoeba', 'paramecium']);
ap.get('firstObject');                        // 'amoeba'

This class can also be useful as a layer to transform the contents of an array, as they are accessed. This can be done by overriding objectAtContent:

import { A } from '@ember/array';
import ArrayProxy from '@ember/array/proxy';

let pets = ['dog', 'cat', 'fish'];
let ap = ArrayProxy.create({
    content: A(pets),
    objectAtContent: function(idx) {
        return this.get('content').objectAt(idx).toUpperCase();
    }
});

ap.get('firstObject'); // . 'DOG'

When overriding this class, it is important to place the call to _super after setting content so the internal observers have a chance to fire properly:

import { A } from '@ember/array';
import ArrayProxy from '@ember/array/proxy';

export default ArrayProxy.extend({
  init() {
    this.set('content', A(['dog', 'cat', 'fish']));
    this._super(...arguments);
  }
});

Show:

obj
*

object to add, if not already present

returns
EmberArray

receiver

Push the object onto the end of the array if it is not already present in the array.

let cities = ['Chicago', 'Berlin'];

cities.addObject('Lima');    // ['Chicago', 'Berlin', 'Lima']
cities.addObject('Berlin');  // ['Chicago', 'Berlin', 'Lima']
objects
EmberArray

the objects to add.

returns
EmberArray

receiver

Adds each object in the passed array to the receiver.

key
String

The key to observe

target
Object

The target object to invoke

method
String|Function

The method to invoke

sync
Boolean

Whether the observer is sync or not

returns
Observable

Adds an observer on a property.

This is the core method used to register an observer for a property.

Once you call this method, any time the key's value is set, your observer will be notified. Note that the observers are triggered any time the value is set, regardless of whether it has actually changed. Your observer should be prepared to handle that.

There are two common invocation patterns for .addObserver():

  • Passing two arguments:
  • the name of the property to observe (as a string)
  • the function to invoke (an actual function)
  • Passing three arguments:
  • the name of the property to observe (as a string)
  • the target object (will be used to look up and invoke a function on)
  • the name of the function to invoke on the target object (as a string).
app/components/my-component.js
import Component from '@ember/component';

export default Component.extend({
  init() {
    this._super(...arguments);

    // the following are equivalent:

    // using three arguments
    this.addObserver('foo', this, 'fooDidChange');

    // using two arguments
    this.addObserver('foo', (...args) => {
      this.fooDidChange(...args);
    });
  },

  fooDidChange() {
    // your custom logic code
  }
});

Observer Methods

Observer methods have the following signature:

app/components/my-component.js
import Component from '@ember/component';

export default Component.extend({
  init() {
    this._super(...arguments);
    this.addObserver('foo', this, 'fooDidChange');
  },

  fooDidChange(sender, key, value, rev) {
    // your code
  }
});

The sender is the object that changed. The key is the property that changes. The value property is currently reserved and unused. The rev is the last property revision of the object when it changed, which you can use to detect if the key value has really changed or not.

Usually you will not need the value or revision parameters at the end. In this case, it is common to write observer methods that take only a sender and key value as parameters or, if you aren't interested in any of these values, to write an observer that has no parameters at all.

callback
Function

The callback to execute

target
Object

The target object to use

returns
Boolean

true if the passed function returns true for any item

The any() method executes the callback function once for each element present in the array until it finds the one where callback returns a truthy value (i.e. true). If such an element is found, any() immediately returns true. Otherwise, any() returns false.

function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array object itself.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. It can be a good way to give your iterator function access to an object in cases where an ES6 arrow function would not be appropriate.

Usage Example:

let includesManager = people.any(this.findPersonInManagersList, this);

let includesStockHolder = people.any(person => {
  return this.findPersonInStockHoldersList(person)
});

if (includesManager || includesStockHolder) {
  Paychecks.addBiggerBonus();
}
keyName
String
returns
Object

The cached value of the computed property, if any

Returns the cached value of a computed property, if it exists. This allows you to inspect the value of a computed property without accidentally invoking it if it is intended to be generated lazily.

returns
Array

An empty Array.

Remove all elements from the array. This is useful if you want to reuse an existing array without having to recreate it.

let colors = ['red', 'green', 'blue'];

colors.length;  // 3
colors.clear(); // []
colors.length;  // 0
returns
Array

the array without null and undefined elements.

Returns a copy of the array with all null and undefined elements removed.

let arr = ['a', null, 'c', undefined];
arr.compact();  // ['a', 'c']
keyName
String

The name of the property to decrement

decrement
Number

The amount to decrement by. Defaults to 1

returns
Number

The new property value

Set the value of a property to the current value minus some amount.

player.decrementProperty('lives');
orc.decrementProperty('health', 5);
returns
EmberObject

receiver

Destroys an object by setting the isDestroyed flag and removing its metadata, which effectively destroys observers and bindings.

If you try to set a property on a destroyed object, an exception will be raised.

Note that destruction is scheduled for the end of the run loop and does not happen immediately. It will set an isDestroying flag immediately.

callback
Function

The callback to execute

target
Object

The target object to use

returns
Boolean

Returns true if the passed function returns true for every item in the enumeration. This corresponds with the Array.prototype.every() method defined in ES5.

The callback method should have the following signature:

function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array itself.

All params are optional. The method should return true or false.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

Usage example:

function isAdult(person) {
  return person.age > 18;
};

const people = Ember.A([{ name: 'John', age: 24 }, { name: 'Joan', age: 45 }]);
const areAllAdults = people.every(isAdult);
callback
Function

The callback to execute

target
Object

The target object to use

returns
Array

A filtered array.

Returns a new array with all of the items in the enumeration that the provided callback function returns true for. This method corresponds to Array.prototype.filter().

The callback method should have the following signature:

function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array itself.

All parameters are optional. The function should return true to include the item in the results, and false otherwise.

Example:

function isAdult(person) {
  return person.age > 18;
};

let people = Ember.A([{ name: 'John', age: 14 }, { name: 'Joan', age: 45 }]);

people.filter(isAdult); // returns [{ name: 'Joan', age: 45 }];

Note that in addition to a callback, you can pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object. For example:

function isAdultAndEngineer(person) {
  return person.age > 18 && this.engineering;
}

class AdultsCollection {
  engineering = false;

  constructor(opts = {}) {
    super(...arguments);

    this.engineering = opts.engineering;
    this.people = Ember.A([{ name: 'John', age: 14 }, { name: 'Joan', age: 45 }]);
  }
}

let collection = new AdultsCollection({ engineering: true });
collection.people.filter(isAdultAndEngineer, { target: collection });
key
String

the property to test

value
*

optional value to test against.

returns
Array

filtered array

Filters the array by the property and an optional value. If a value is given, it returns the items that have said value for the property. If not, it returns all the items that have a truthy value for the property.

Example Usage:

let things = Ember.A([{ food: 'apple', isFruit: true }, { food: 'beans', isFruit: false }]);

things.filterBy('food', 'beans'); // [{ food: 'beans', isFruit: false }]
things.filterBy('isFruit'); // [{ food: 'apple', isFruit: true }]
callback
Function

The callback to execute

target
Object

The target object to use

returns
Object

Found item or undefined.

Returns the first item in the array for which the callback returns true. This method is similar to the find() method defined in ECMAScript 2015.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array itself.

It should return the true to include the item in the results, false otherwise.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

Example Usage:

let users = [
  { id: 1, name: 'Yehuda' },
  { id: 2, name: 'Tom' },
  { id: 3, name: 'Melanie' },
  { id: 4, name: 'Leah' }
];

users.find((user) => user.name == 'Tom'); // [{ id: 2, name: 'Tom' }]
users.find(({ id }) => id == 3); // [{ id: 3, name: 'Melanie' }]
key
String

the property to test

value
String

optional value to test against.

returns
Object

found item or undefined

Returns the first item with a property matching the passed value. You can pass an optional second argument with the target value. Otherwise this will match any property that evaluates to true.

This method works much like the more generic find() method.

Usage Example:

let users = [
  { id: 1, name: 'Yehuda', isTom: false },
  { id: 2, name: 'Tom', isTom: true },
  { id: 3, name: 'Melanie', isTom: false },
  { id: 4, name: 'Leah', isTom: false }
];

users.findBy('id', 4); // { id: 4, name: 'Leah', isTom: false }
users.findBy('name', 'Melanie'); // { id: 3, name: 'Melanie', isTom: false }
users.findBy('isTom'); // { id: 2, name: 'Tom', isTom: true }
callback
Function

The callback to execute

target
Object

The target object to use

returns
Object

receiver

Iterates through the array, calling the passed function on each item. This method corresponds to the forEach() method defined in JavaScript 1.6.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array itself.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

Example Usage:

let foods = [
  { name: 'apple', eaten: false },
  { name: 'banana', eaten: false },
  { name: 'carrot', eaten: false }
];

foods.forEach((food) => food.eaten = true);

let output = '';
foods.forEach((item, index, array) =>
  output += `${index + 1}/${array.length} ${item.name}\n`;
);
console.log(output);
// 1/3 apple
// 2/3 banana
// 3/3 carrot
keyName
String

The property to retrieve

returns
Object

The property value or undefined.

Retrieves the value of a property from the object.

This method is usually similar to using object[keyName] or object.keyName, however it supports both computed properties and the unknownProperty handler.

Because get unifies the syntax for accessing all these kinds of properties, it can make many refactorings easier, such as replacing a simple property with a computed property, or vice versa.

Computed Properties

Computed properties are methods defined with the property modifier declared at the end, such as:

import { computed } from '@ember/object';

fullName: computed('firstName', 'lastName', function() {
  return this.get('firstName') + ' ' + this.get('lastName');
})

When you call get on a computed property, the function will be called and the return value will be returned instead of the function itself.

Unknown Properties

Likewise, if you try to call get on a property whose value is undefined, the unknownProperty() method will be called on the object. If this method returns any value other than undefined, it will be returned instead. This allows you to implement "virtual" properties that are not defined upfront.

key
String

name of the property

returns
Array

The mapped array.

Alias for mapBy.

Returns the value of the named property on all items in the enumeration.

let people = [{name: 'Joe'}, {name: 'Matt'}];

people.getEach('name');
// ['Joe', 'Matt'];

people.getEach('nonexistentProperty');
// [undefined, undefined];
list
String...|Array

of keys to get

returns
Object

To get the values of multiple properties at once, call getProperties with a list of strings or an array:

record.getProperties('firstName', 'lastName', 'zipCode');
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }

is equivalent to:

record.getProperties(['firstName', 'lastName', 'zipCode']);
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }
object
Object

The object to search for.

startAt
Number

optional starting location to search, default 0

returns
Boolean

true if object is found in the array.

Used to determine if the array contains the passed object. Returns true if found, false otherwise.

The optional startAt argument can be used to pass a starting index to search from, effectively slicing the searchable portion of the array. If it's negative it will add the array length to the startAt value passed in as the index to search from. If less than or equal to -1 * array.length the entire array is searched.

This method has the same behavior of JavaScript's Array.includes.

[1, 2, 3].includes(2);     // true
[1, 2, 3].includes(4);     // false
[1, 2, 3].includes(3, 2);  // true
[1, 2, 3].includes(3, 3);  // false
[1, 2, 3].includes(3, -1); // true
[1, 2, 3].includes(1, -1); // false
[1, 2, 3].includes(1, -4); // true
[1, 2, NaN].includes(NaN); // true
keyName
String

The name of the property to increment

increment
Number

The amount to increment by. Defaults to 1

returns
Number

The new property value

Set the value of a property to the current value plus some amount.

person.incrementProperty('age');
team.incrementProperty('score', 2);
object
Object

the item to search for

startAt
Number

optional starting location to search, default 0

returns
Number

index or -1 if not found

Used to determine the passed object's first occurrence in the array. Returns the index if found, -1 if no match is found.

The optional startAt argument can be used to pass a starting index to search from, effectively slicing the searchable portion of the array. If it's negative it will add the array length to the startAt value passed in as the index to search from. If less than or equal to -1 * array.length the entire array is searched.

let arr = ['a', 'b', 'c', 'd', 'a'];

arr.indexOf('a');       //  0
arr.indexOf('z');       // -1
arr.indexOf('a', 2);    //  4
arr.indexOf('a', -1);   //  4, equivalent to indexOf('a', 4)
arr.indexOf('a', -100); //  0, searches entire array
arr.indexOf('b', 3);    // -1
arr.indexOf('a', 100);  // -1

let people = [{ name: 'Zoey' }, { name: 'Bob' }]
let newPerson = { name: 'Tom' };
people = [newPerson, ...people, newPerson];

people.indexOf(newPerson);     //  0
people.indexOf(newPerson, 1);  //  3
people.indexOf(newPerson, -4); //  0
people.indexOf(newPerson, 10); // -1

An overridable method called when objects are instantiated. By default, does nothing unless it is overridden during class definition.

Example:

import EmberObject from '@ember/object';

const Person = EmberObject.extend({
  init() {
    alert(`Name is ${this.get('name')}`);
  }
});

let steve = Person.create({
  name: 'Steve'
});

// alerts 'Name is Steve'.

NOTE: If you do override init for a framework class like Component from @ember/component, be sure to call this._super(...arguments) in your init declaration! If you don't, Ember may not have an opportunity to do important setup work, and you'll see strange behavior in your application.

idx
Number

index of insert the object at.

object
Object

object to insert

returns
EmberArray

receiver

This will use the primitive replace() method to insert an object at the specified index.

let colors = ['red', 'green', 'blue'];

colors.insertAt(2, 'yellow');  // ['red', 'green', 'yellow', 'blue']
colors.insertAt(5, 'orange');  // Error: Index out of range
methodName
String

the name of the method

args
Object...

optional arguments to pass as well.

returns
Array

return values from calling invoke.

Invokes the named method on every object in the receiver that implements it. This method corresponds to the implementation in Prototype 1.6.

class Person {
  name = null;

  constructor(name) {
    this.name = name;
  }

  greet(prefix='Hello') {
    return `${prefix} ${this.name}`;
  }
}

let people = [new Person('Joe'), new Person('Matt')];

people.invoke('greet'); // ['Hello Joe', 'Hello Matt']
people.invoke('greet', 'Bonjour'); // ['Bonjour Joe', 'Bonjour Matt']

Available since v1.3.0

key
String

the property to test

value
String

optional value to test against. Defaults to true

returns
Boolean

Returns true if the passed property resolves to the value of the second argument for any item in the array. This method is often simpler/faster than using a callback.

Example usage:

const food = [
  { food: 'apple', isFruit: true },
  { food: 'bread', isFruit: false },
  { food: 'banana', isFruit: true }
];

food.isAny('isFruit'); // true

Available since v1.3.0

key
String

the property to test

value
String

optional value to test against. Defaults to true

returns
Boolean

Returns true if the passed property resolves to the value of the second argument for all items in the array. This method is often simpler/faster than using a callback.

Note that like the native Array.every, isEvery will return true when called on any empty array.

class Language {
  constructor(name, isProgrammingLanguage) {
    this.name = name;
    this.programmingLanguage = isProgrammingLanguage;
  }
}

const compiledLanguages = [
  new Language('Java', true),
  new Language('Go', true),
  new Language('Rust', true)
]

const languagesKnownByMe = [
  new Language('Javascript', true),
  new Language('English', false),
  new Language('Ruby', true)
]

compiledLanguages.isEvery('programmingLanguage'); // true
languagesKnownByMe.isEvery('programmingLanguage'); // false
object
Object

the item to search for

startAt
Number

optional starting location to search from backwards, defaults to (array.length - 1)

returns
Number

The last index of the object in the array or -1 if not found

Returns the index of the given object's last occurrence.

  • If no startAt argument is given, the search starts from the last position.
  • If it's greater than or equal to the length of the array, the search starts from the last position.
  • If it's negative, it is taken as the offset from the end of the array i.e. startAt + array.length.
  • If it's any other positive number, will search backwards from that index of the array.

Returns -1 if no match is found.

let arr = ['a', 'b', 'c', 'd', 'a'];

arr.lastIndexOf('a');       //  4
arr.lastIndexOf('z');       // -1
arr.lastIndexOf('a', 2);    //  0
arr.lastIndexOf('a', -1);   //  4
arr.lastIndexOf('a', -3);   //  0
arr.lastIndexOf('b', 3);    //  1
arr.lastIndexOf('a', 100);  //  4
callback
Function

The callback to execute

target
Object

The target object to use

returns
Array

The mapped array.

Maps all of the items in the enumeration to another value, returning a new array. This method corresponds to map() defined in JavaScript 1.6.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, array);
let arr = [1, 2, 3, 4, 5, 6];

arr.map(element => element * element);
// [1, 4, 9, 16, 25, 36];

arr.map((element, index) => element + index);
// [1, 3, 5, 7, 9, 11];
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array itself.

It should return the mapped value.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

key
String

name of the property

returns
Array

The mapped array.

Similar to map, this specialized function returns the value of the named property on all items in the enumeration.

let people = [{name: 'Joe'}, {name: 'Matt'}];

people.mapBy('name');
// ['Joe', 'Matt'];

people.mapBy('unknownProperty');
// [undefined, undefined];
keyName
String

The property key to be notified about.

returns
Observable

Convenience method to call propertyWillChange and propertyDidChange in succession.

Notify the observer system that a property has just changed.

Sometimes you need to change a value directly or indirectly without actually calling get() or set() on it. In this case, you can use this method instead. Calling this method will notify all observers that the property has potentially changed value.

idx
Number

The index of the item to return.

returns
*

item at index or undefined

Returns the object at the given index. If the given index is negative or is greater or equal than the array length, returns undefined.

This is one of the primitives you must implement to support EmberArray. If your object supports retrieving the value of an array item using get() (i.e. myArray.get(0)), then you do not need to implement this method yourself.

let arr = ['a', 'b', 'c', 'd'];

arr.objectAt(0);   // 'a'
arr.objectAt(3);   // 'd'
arr.objectAt(-1);  // undefined
arr.objectAt(4);   // undefined
arr.objectAt(5);   // undefined
idx
Number

The index to retrieve.

returns
Object

the value or undefined if none found

Should actually retrieve the object at the specified index from the content. You can override this method in subclasses to transform the content item to something new.

This method will only be called if content is non-null.

indexes
Array

An array of indexes of items to return.

returns
Array

This returns the objects at the specified indexes, using objectAt.

let arr = ['a', 'b', 'c', 'd'];

arr.objectsAt([0, 1, 2]);  // ['a', 'b', 'c']
arr.objectsAt([2, 3, 4]);  // ['c', 'd', undefined]
returns

object

Pop object from array or nil if none are left. Works just like pop() but it is KVO-compliant.

let colors = ['red', 'green', 'blue'];

colors.popObject();   // 'blue'
console.log(colors);  // ['red', 'green']
obj
*

object to push

returns

object same object passed as a param

Push the object onto the end of the array. Works just like push() but it is KVO-compliant.

let colors = ['red', 'green'];

colors.pushObject('black');     // ['red', 'green', 'black']
colors.pushObject(['yellow']);  // ['red', 'green', ['yellow']]
objects
Array

the objects to add

returns
MutableArray

receiver

Add the objects in the passed array to the end of the array. Defers notifying observers of the change until all objects are added.

let colors = ['red'];

colors.pushObjects(['yellow', 'orange']);  // ['red', 'yellow', 'orange']
callback
Function

The callback to execute

initialValue
Object

Initial value for the reduce

returns
Object

The reduced value.

This will combine the values of the array into a single value. It is a useful way to collect a summary value from an array. This corresponds to the reduce() method defined in JavaScript 1.8.

The callback method you provide should have the following signature (all parameters are optional):

function(previousValue, item, index, array);
  • previousValue is the value returned by the last call to the iterator.
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array itself.

Return the new cumulative value.

In addition to the callback you can also pass an initialValue. An error will be raised if you do not pass an initial value and the enumerator is empty.

Note that unlike the other methods, this method does not allow you to pass a target object to set as this for the callback. It's part of the spec. Sorry.

Example Usage:

  let numbers = [1, 2, 3, 4, 5];

  numbers.reduce(function(summation, current) {
    return summation + current;
  }); // 15 (1 + 2 + 3 + 4 + 5)

  numbers.reduce(function(summation, current) {
    return summation + current;
  }, -15); // 0 (-15 + 1 + 2 + 3 + 4 + 5)


  let binaryValues = [true, false, false];

  binaryValues.reduce(function(truthValue, current) {
    return truthValue && current;
  }); // false (true && false && false)
callback
Function

The callback to execute

target
Object

The target object to use

returns
Array

A rejected array.

Returns an array with all of the items in the enumeration where the passed function returns false. This method is the inverse of filter().

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration
  • array is the array itself.

It should return a falsey value to include the item in the results.

Note that in addition to a callback, you can also pass an optional target object that will be set as "this" on the context. This is a good way to give your iterator function access to the current object.

Example Usage:

const food = [
  { food: 'apple', isFruit: true },
  { food: 'bread', isFruit: false },
  { food: 'banana', isFruit: true }
];
const nonFruits = food.reject(function(thing) {
  return thing.isFruit;
}); // [{food: 'bread', isFruit: false}]
key
String

the property to test

value
*

optional value to test against.

returns
Array

rejected array

Returns an array with the items that do not have truthy values for the provided key. You can pass an optional second argument with a target value to reject for the key. Otherwise this will reject objects where the provided property evaluates to false.

Example Usage:

  let food = [
    { name: "apple", isFruit: true },
    { name: "carrot", isFruit: false },
    { name: "bread", isFruit: false },
  ];
  food.rejectBy('isFruit'); // [{ name: "carrot", isFruit: false }, { name: "bread", isFruit: false }]
  food.rejectBy('name', 'carrot'); // [{ name: "apple", isFruit: true }}, { name: "bread", isFruit: false }]
start
Number

index, start of range

len
Number

length of passing range

returns
EmberArray

receiver

Remove an object at the specified index using the replace() primitive method. You can pass either a single index, or a start and a length.

If you pass a start and length that is beyond the length this method will throw an assertion.

let colors = ['red', 'green', 'blue', 'yellow', 'orange'];

colors.removeAt(0);     // ['green', 'blue', 'yellow', 'orange']
colors.removeAt(2, 2);  // ['green', 'blue']
colors.removeAt(4, 2);  // Error: Index out of range
obj
*

object to remove

returns
EmberArray

receiver

Remove all occurrences of an object in the array.

let cities = ['Chicago', 'Berlin', 'Lima', 'Chicago'];

cities.removeObject('Chicago');  // ['Berlin', 'Lima']
cities.removeObject('Lima');     // ['Berlin']
cities.removeObject('Tokyo')     // ['Berlin']
objects
EmberArray

the objects to remove

returns
EmberArray

receiver

Removes each object in the passed array from the receiver.

key
String

The key to observe

target
Object

The target object to invoke

method
String|Function

The method to invoke

sync
Boolean

Whether the observer is async or not

returns
Observable

Remove an observer you have previously registered on this object. Pass the same key, target, and method you passed to addObserver() and your target will no longer receive notifications.

idx
Number

Starting index in the array to replace. If idx >= length, then append to the end of the array.

amt
Number

Number of elements that should be removed from the array, starting at idx.

objects
EmberArray

An optional array of zero or more objects that should be inserted into the array at idx

Required. You must implement this method to apply this mixin.

This is one of the primitives you must implement to support Array. You should replace amt objects started at idx with the objects in the passed array.

Note that this method is expected to validate the type(s) of objects that it expects.

idx
Number

The starting index

amt
Number

The number of items to remove from the content.

objects
Array

Optional array of objects to insert.

returns
Void

Should actually replace the specified objects on the content array. You can override this method in subclasses to transform the content item into something new.

This method will only be called if content is non-null.

returns
EmberArray

receiver

Reverse objects in the array. Works just like reverse() but it is KVO-compliant.

keyName
String

The property to set

value
Object

The value to set or null.

returns
Object

The passed value

Sets the provided key or path to the value.

record.set("key", value);

This method is generally very similar to calling object["key"] = value or object.key = value, except that it provides support for computed properties, the setUnknownProperty() method and property observers.

Computed Properties

If you try to set a value on a key that has a computed property handler defined (see the get() method for an example), then set() will call that method, passing both the value and key instead of simply changing the value itself. This is useful for those times when you need to implement a property that is composed of one or more member properties.

Unknown Properties

If you try to set a value on a key that is undefined in the target object, then the setUnknownProperty() handler will be called instead. This gives you an opportunity to implement complex "virtual" properties that are not predefined on the object. If setUnknownProperty() returns undefined, then set() will simply set the value on the object.

Property Observers

In addition to changing the property, set() will also register a property change with the object. Unless you have placed this call inside of a beginPropertyChanges() and endPropertyChanges(), any "local" observers (i.e. observer methods declared on the same object), will be called immediately. Any "remote" observers (i.e. observer methods declared on another object) will be placed in a queue and called at a later time in a coalesced manner.

key
String

The key to set

value
Object

The object to set

returns
Object

receiver

Sets the value on the named property for each member. This is more ergonomic than using other methods defined on this helper. If the object implements Observable, the value will be changed to set(), otherwise it will be set directly. null objects are skipped.

let people = [{name: 'Joe'}, {name: 'Matt'}];

people.setEach('zipCode', '10011');
// [{name: 'Joe', zipCode: '10011'}, {name: 'Matt', zipCode: '10011'}];
objects
EmberArray

array whose content will be used for replacing the content of the receiver

returns
EmberArray

receiver with the new content

Replace all the receiver's content with content of the argument. If argument is an empty array receiver will be cleared.

let colors = ['red', 'green', 'blue'];

colors.setObjects(['black', 'white']);  // ['black', 'white']
colors.setObjects([]);                  // []
hash
Object

the hash of keys and values to set

returns
Object

The passed in hash

Sets a list of properties at once. These properties are set inside a single beginPropertyChanges and endPropertyChanges batch, so observers will be buffered.

record.setProperties({ firstName: 'Charles', lastName: 'Jolley' });
returns

object

Shift an object from start of array or nil if none are left. Works just like shift() but it is KVO-compliant.

let colors = ['red', 'green', 'blue'];

colors.shiftObject();  // 'red'
console.log(colors);   // ['green', 'blue']
beginIndex
Number

(Optional) index to begin slicing from.

endIndex
Number

(Optional) index to end the slice at (but not included).

returns
Array

New array with specified slice

Returns a new array that is a slice of the receiver. This implementation uses the observable array methods to retrieve the objects for the new slice.

let arr = ['red', 'green', 'blue'];

arr.slice(0);       // ['red', 'green', 'blue']
arr.slice(0, 2);    // ['red', 'green']
arr.slice(1, 100);  // ['green', 'blue']

Available since v1.2.0

property
String

name(s) to sort on

returns
Array

The sorted array.

Sorts the array by the keys specified in the argument.

You may provide multiple arguments to sort by multiple properties.

   let colors = [
 { name: 'red', weight: 500 },
 { name: 'green', weight: 600 },
 { name: 'blue', weight: 500 }
];

   colors.sortBy('name');
   // [{name: 'blue', weight: 500}, {name: 'green', weight: 600}, {name: 'red', weight: 500}]

   colors.sortBy('weight', 'name');
   // [{name: 'blue', weight: 500}, {name: 'red', weight: 500}, {name: 'green', weight: 600}]
returns
Array

the object as an array.

Simply converts the object into a genuine array. The order is not guaranteed. Corresponds to the method implemented by Prototype.

returns
String

string representation

Returns a string representation which attempts to provide more information than Javascript's toString typically does, in a generic way for all Ember objects.

import EmberObject from '@ember/object';

const Person = EmberObject.extend();
person = Person.create();
person.toString(); //=> "<Person:ember1024>"

If the object's class is not defined on an Ember namespace, it will indicate it is a subclass of the registered superclass:

const Student = Person.extend();
let student = Student.create();
student.toString(); //=> "<(subclass of Person):ember1025>"

If the method toStringExtension is defined, its return value will be included in the output.

const Teacher = Person.extend({
  toStringExtension() {
    return this.get('fullName');
  }
});
teacher = Teacher.create();
teacher.toString(); //=> "<Teacher:ember1026:Tom Dale>"
keyName
String

The name of the property to toggle

returns
Boolean

The new property value

Set the value of a boolean property to the opposite of its current value.

starship.toggleProperty('warpDriveEngaged');
returns
EmberArray

Returns a new array that contains only unique values. The default implementation returns an array regardless of the receiver type.

let arr = ['a', 'a', 'b', 'b'];
arr.uniq();  // ['a', 'b']

This only works on primitive data types, e.g. Strings, Numbers, etc.

key
String,Function
returns
EmberArray

Returns a new array that contains only items containing a unique property value. The default implementation returns an array regardless of the receiver type.

let arr = [{ value: 'a' }, { value: 'a' }, { value: 'b' }, { value: 'b' }];
arr.uniqBy('value');  // [{ value: 'a' }, { value: 'b' }]

let arr = [2.2, 2.1, 3.2, 3.3];
arr.uniqBy(Math.floor);  // [2.2, 3.2];
obj
*

object to unshift

returns

object same object passed as a param

Unshift an object to start of array. Works just like unshift() but it is KVO-compliant.

let colors = ['red'];

colors.unshiftObject('yellow');    // ['yellow', 'red']
colors.unshiftObject(['black']);   // [['black'], 'yellow', 'red']
objects
Enumerable

the objects to add

returns
EmberArray

receiver

Adds the named objects to the beginning of the array. Defers notifying observers until all objects have been added.

let colors = ['red'];

colors.unshiftObjects(['black', 'white']);   // ['black', 'white', 'red']
colors.unshiftObjects('yellow'); // Type Error: 'undefined' is not a function

Override to implement teardown.

value
Object
returns
EmberArray

Returns a new array that excludes the passed value. The default implementation returns an array regardless of the receiver type. If the receiver does not contain the value it returns the original array.

let arr = ['a', 'b', 'a', 'c'];
arr.without('a');  // ['b', 'c']