Attribute Change with didUpdateAttrs

The didUpdateAttrs hook can be used when component's attributes have changed and called before re-rendering the component.

Syntax

import Ember from 'ember';

export default Ember.Component.extend ({
   ...
   didUpdateAttrs() {
      //code here    
   },
   ...
})

Example

The example given below describes the use of didUpdateAttrs hook to be used when the component's attributes have changed. Create a component with the name post-action which will get defined under app/components/.

Open the post-action.js file and add the following code −

import Ember from 'ember';

export default Ember.Component.extend ({
   didInitAttrs(options) {
      console.log('didInitAttrs', options);
   },

   didUpdateAttrs(options) {
      console.log('didUpdateAttrs', options);
   },

   willUpdate(options) {
      console.log('willUpdate', options);
   },

   didReceiveAttrs(options) {
      console.log('didReceiveAttrs', options);
   },

   willRender() {
      console.log('willRender');
   },

   didRender() {
      console.log('didRender');
   },

   didInsertElement() {
      console.log('didInsertElement');
   },

   didUpdate(options) {
      console.log('didUpdate', options);
   },
});

Now open the component template file post-action.hbs with the following code −

<p>name: {{name}}</p>
<p>attrs.data.a: {{attrs.data.a}} is in console</p>
{{yield}}

Open the index.hbs file and add the following code −

<div>
   <p>appName: {{input type = "text" value = appName}}</p>
   <p>Triggers: didUpdateAttrs, didReceiveAttrs, willUpdate, willRender, 
      didUpdate, didRender</p>
</div>

<div>
   <p>data.a: {{input type = "text" value = data.a}}</p>
</div>
<hr>

{{post-action name = appName data = data}}
{{outlet}}

Create an index.js file under app/controller/ with the following code −

import Ember from 'ember';

export default Ember.Controller.extend ({
   appName:'TutorialsPoint',
   data: {
      a: 'output',
   }
});

Output

Run the ember server; you will receive the following output −

Open the console and you will get the output as shown in the screenshot below −