Function
readOnly (dependentKey) ComputedProperty public
| Module: | @ember/object |
|---|
Defined in packages/ember-runtime/lib/computed/computed_macros.js:598
Available since v1.5.0
import { readOnly } from '@ember/object/computed'; - dependentKey
- String
- returns
- ComputedProperty
- computed property which creates a one way computed property to the original value for property.
Where computed.oneWay provides oneWay bindings, computed.readOnly provides a readOnly one way binding. Very often when using computed.oneWay one does not also want changes to propagate back up, as they will replace the value.
This prevents the reverse flow, and also throws an exception when it occurs.
Example
let User = Ember.Object.extend({
firstName: null,
lastName: null,
nickName: Ember.computed.readOnly('firstName')
});
let teddy = User.create({
firstName: 'Teddy',
lastName: 'Zeenny'
});
teddy.get('nickName'); // 'Teddy'
teddy.set('nickName', 'TeddyBear'); // throws Exception
// throw new Ember.Error('Cannot Set: nickName on: <User:ember27288>' );`
teddy.get('firstName'); // 'Teddy'
© 2020 Yehuda Katz, Tom Dale and Ember.js contributors
Licensed under the MIT License.
https://api.emberjs.com/ember/2.18/functions/@ember%2Fobject%2Fcomputed/readOnly