Class CoreObject
publicDefined in: | packages/ember-runtime/lib/system/core_object.js:198 |
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Module: | @ember/object |
concatenatedProperties public
Module: | @ember/object |
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Defined in packages/ember-runtime/lib/system/core_object.js:248
Defines the properties that will be concatenated from the superclass (instead of overridden).
By default, when you extend an Ember class a property defined in the subclass overrides a property with the same name that is defined in the superclass. However, there are some cases where it is preferable to build up a property's value by combining the superclass' property value with the subclass' value. An example of this in use within Ember is the classNames
property of Ember.View
.
Here is some sample code showing the difference between a concatenated property and a normal one:
const Bar = Ember.Object.extend({ // Configure which properties to concatenate concatenatedProperties: ['concatenatedProperty'], someNonConcatenatedProperty: ['bar'], concatenatedProperty: ['bar'] }); const FooBar = Bar.extend({ someNonConcatenatedProperty: ['foo'], concatenatedProperty: ['foo'] }); let fooBar = FooBar.create(); fooBar.get('someNonConcatenatedProperty'); // ['foo'] fooBar.get('concatenatedProperty'); // ['bar', 'foo']
This behavior extends to object creation as well. Continuing the above example:
let fooBar = FooBar.create({ someNonConcatenatedProperty: ['baz'], concatenatedProperty: ['baz'] }) fooBar.get('someNonConcatenatedProperty'); // ['baz'] fooBar.get('concatenatedProperty'); // ['bar', 'foo', 'baz']
Adding a single property that is not an array will just add it in the array:
let fooBar = FooBar.create({ concatenatedProperty: 'baz' }) view.get('concatenatedProperty'); // ['bar', 'foo', 'baz']
Using the concatenatedProperties
property, we can tell Ember to mix the content of the properties.
In Ember.Component
the classNames
, classNameBindings
and attributeBindings
properties are concatenated.
This feature is available for you to use throughout the Ember object model, although typical app developers are likely to use it infrequently. Since it changes expectations about behavior of properties, you should properly document its usage in each individual concatenated property (to not mislead your users to think they can override the property in a subclass).
isDestroyed public
Module: | @ember/object |
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Defined in packages/ember-runtime/lib/system/core_object.js:395
Destroyed object property flag.
if this property is true
the observers and bindings were already removed by the effect of calling the destroy()
method.
isDestroying public
Module: | @ember/object |
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Defined in packages/ember-runtime/lib/system/core_object.js:420
Destruction scheduled flag. The destroy()
method has been called.
The object stays intact until the end of the run loop at which point the isDestroyed
flag is set.
mergedProperties public
Module: | @ember/object |
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Defined in packages/ember-runtime/lib/system/core_object.js:321
Defines the properties that will be merged from the superclass (instead of overridden).
By default, when you extend an Ember class a property defined in the subclass overrides a property with the same name that is defined in the superclass. However, there are some cases where it is preferable to build up a property's value by merging the superclass property value with the subclass property's value. An example of this in use within Ember is the queryParams
property of routes.
Here is some sample code showing the difference between a merged property and a normal one:
const Bar = Ember.Object.extend({ // Configure which properties are to be merged mergedProperties: ['mergedProperty'], someNonMergedProperty: { nonMerged: 'superclass value of nonMerged' }, mergedProperty: { page: { replace: false }, limit: { replace: true } } }); const FooBar = Bar.extend({ someNonMergedProperty: { completelyNonMerged: 'subclass value of nonMerged' }, mergedProperty: { limit: { replace: false } } }); let fooBar = FooBar.create(); fooBar.get('someNonMergedProperty'); // => { completelyNonMerged: 'subclass value of nonMerged' } // // Note the entire object, including the nonMerged property of // the superclass object, has been replaced fooBar.get('mergedProperty'); // => { // page: {replace: false}, // limit: {replace: false} // } // // Note the page remains from the superclass, and the // `limit` property's value of `false` has been merged from // the subclass.
This behavior is not available during object create
calls. It is only available at extend
time.
In Ember.Route
the queryParams
property is merged.
This feature is available for you to use throughout the Ember object model, although typical app developers are likely to use it infrequently. Since it changes expectations about behavior of properties, you should properly document its usage in each individual merged property (to not mislead your users to think they can override the property in a subclass).
© 2020 Yehuda Katz, Tom Dale and Ember.js contributors
Licensed under the MIT License.
https://api.emberjs.com/ember/2.18/classes/CoreObject/properties