How to react on changes in one way bindings

Question

In the following snippet:

angular.module('myModule')
        .component('myComponent', {
            controller : [
                 MyComponentController
            ],
            bindings: {
               input: '<'
            }
        });

According to documentation - section "Components have a well-defined lifecycle" in order to monitor that the binding input has changed we could use $onChanges lifecycle method. I can't make it work.

Thi is how I am using it:

function MyComponentController() { self.$onChanges = function (changesObj){ // some code here } }

But the code doesn't even enter the fuction.

How are you trying to modify the binding? It'd help to see that part of the code too. — Joe Clay, Apr 15 '16 at 10:29
@JoeClay I just got to this issue: https://github.com/angular/angular.js/issues/14030 It seems that I am doing it all well just the Angular v. 1.5.0 has a bug. It should be working in 1.5.3. I am gonna give it a try. — Amio.io, Apr 15 '16 at 10:31
@JoeClay It was indeed the bug. But the release notes state that it was corrected in v.1.5.4. https://github.com/angular/angular.js/blob/master/CHANGELOG.md#154-graduated-sophistry-2016-04-14 — Amio.io, Apr 15 '16 at 10:44
Ah, it's not a bug causing it then! The $onChanges hook actually wasn't added until version 1.5.3. The only hook that was available in 1.5.0 was $onInit. — Joe Clay, Apr 15 '16 at 11:10
Good for you! I have updated the answer with your comment. If you post the answer I am gonna set your answer as correct. — Amio.io, Apr 15 '16 at 11:18

Amio.io · Answer 1 · 2016-04-15T11:17:48.407

1

It was a bug corrected in version 1.5.4.

However, I am using version 1.5.3 and it is working. Strange...

Update

@JoeClay has noticed that it was not a bug at all. The $onChanges was added in version 1.5.3.

edited Apr 15 '16 at 11:17

answered Apr 15 '16 at 10:47

Amio.io

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score 1 · Accepted Answer · answered Apr 15 '16 at 11:24

As we figured out in the comments, the issue was that the $onChanges hook (along with $onDestroy and $postLink) was not added until version 1.5.3 of Angular, and zatziky was using 1.5.0, which only implements the $onInit hook. Seems a bit strange for them to add such a big feature in a patch level release, but at least it was an easy fix.

How to react on changes in one way bindings

2 Answers2