Function
readOnly (dependentKey) ComputedProperty public
Module:
@ember/object
Defined in packages/@ember/object/lib/computed/computed_macros.ts:745
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 oneWay
computed macro provides oneWay bindings, the readOnly
computed macro provides a readOnly one way binding. Very often when using
the oneWay
macro 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:
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import { set } from '@ember/object'; import { readOnly } from '@ember/object/computed'; class User { constructor(firstName, lastName) { set(this, 'firstName', firstName); set(this, 'lastName', lastName); } nickName; }); let teddy = new User('Teddy', 'Zeenny'); teddy.nickName; // 'Teddy' set(teddy, 'nickName', 'TeddyBear'); // throws Exception // throw new EmberError('Cannot Set: nickName on: <User:ember27288>' );` teddy.firstName; // 'Teddy' |