where do we use $parent in angularjs?

Question

I was really confused with this example from angular documentation plunker and angular docs

here I have removed $parent inside a ng-repeat but it is still working fine..?

why do we need to add that in ng-repeat because each iteration will have its own $scope and this will evaluate. why do we required previous or $parent scope.

scopes are all about accessibility of their relative properties while you're targeting nested scoping. — Amit Kumar Ghosh, Apr 11 '16 at 11:33
this i got from other question where do we use $parent in ng-repeat http://stackoverflow.com/questions/16573954/pass-parent-scope-value-into-ng-repeat-loop-in-angular — santhosh, Apr 11 '16 at 12:13

score 1 · Accepted Answer · answered Apr 11 '16 at 11:31

1

It depends upon what you are trying to achieve, if you are not using controller As syntax, you would need $parent to access the parent controllers scope in a nested structure.

<div ng-controller="ParentController">
    <div ng-controller="ChildController">
    </div>
</div>

Then you can access the parent scope as follows

function ParentController($scope) {
    $scope.states= ["Chennai", "Kerala", "Spain"];
}

function ChildController($scope) {    
}

Now you could do something from your view...

<div ng-app ng-controller="ParentController">
    <div ng-controller="ChildController">
       {{$parent.states}}
    </div>
</div>

Now coming to case of your comment on a isolated scope, we could use $parent to access the property in parent scope but you could use the scope property (@ , = , &) where you can specify which scope properties you need to work with.

answered Apr 11 '16 at 11:31

Thalaivar

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your answer cleared my doudts. but why do that punker example ng-repeat using $parent. its not required their right – santhosh Apr 11 '16 at 11:36
see this example its not working with $parent or i was wrong http://plnkr.co/edit/scMSESFRj6QAwDvq4Xuk?p=preview – santhosh Apr 11 '16 at 11:42
It should work, plunkr for me does not work properly here... here is a fiddle... http://jsfiddle.net/zstL0so5/ – Thalaivar Apr 11 '16 at 11:44
ohh but in fiddle you have not added any cdn for angularjs – santhosh Apr 11 '16 at 11:47
strange it works... i forked a normal angularjs fiddle... may be it has some references... – Thalaivar Apr 11 '16 at 11:50

score 0 · Answer 2 · answered Apr 11 '16 at 11:27

0

$parent is often use when people don't really know what they're doing of with some kind of tricky directives.

Usually if you don't want to have to use $parent. Use dot notation :

$scope.toto = "titi";//not a dot notation
$scope.fields = {toto:"titi"};// dot notation

Having an intermediary object will make sure that you won't have any problems between scope that inherits from each others. This is a du to a limit of javascript.

answered Apr 11 '16 at 11:27

Walfrat

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can you give me an example for the tricky directive as you have mentioned – santhosh Apr 11 '16 at 11:30
@santhosh: you would use the scope property of the directive to access the properties from the parent scope via (@, = and &) much preferred way. – Thalaivar Apr 11 '16 at 11:35
@santhosh i just saw some people doing that on the net but in the end i never had to use $parent myself as long as i respected the dot notation. I can just say that it may happens with directives that inherits their scope from parent's scope ( **scope:true** in the definition of the directive). – Walfrat Apr 11 '16 at 11:47

where do we use $parent in angularjs?

2 Answers2