How to get parent element inside ng-include when iterating in ng-repeat recursively

All we need is an easy explanation of the problem, so here it is.

I made a recursive ng-repeat element, and trying to manipulate things has turned into a nightmare, because I don’t have reference to the parent I’m iterating over.

The ng-repeat looks like this:

ng-repeat="(key, value) in value"

Remember It’s recursive, so each value in value becomes the new value, so I can’t just use the “in” value from ng-repeat. I want to do such things as checking if the parent is an array, but $parent is some weird thing, not the parent element of the current iteration value.

Some examples of things I want to do is:

ng-show="isArray(parent)"
ng-click="delete(parent, $index)"

(as an example of what I’m doing as a work around, I’ve had to add an ___ISARRAYELEMENT___ property to each of my array elements, just to know that it’s in an array >.>;;)

EDIT: Basically I want to know if there is any convenient meta data in an ng-repeat context that I’m missing.

EDIT: Ok here is the html in it’s entirety:

<html ng-app>
<head>
    <title>JSON CRUD</title>
    <link href="//netdna.bootstrapcdn.com/bootstrap/3.0.3/css/bootstrap.min.css" rel="nofollow noreferrer noopener" rel="stylesheet">
    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
    <script src="//netdna.bootstrapcdn.com/bootstrap/3.0.3/js/bootstrap.min.js"></script>
    <script src="//ajax.googleapis.com/ajax/libs/angularjs/1.2.6/angular.min.js"></script>
    <script src="angularjsoncrud.js"></script>
    <script type="text/ng-template" id="node.html">
        <button ng-click="minimized = !minimized" ng-show="!isLeaf(value)" ng-init="minimized=false" ng-class="{'glyphicon glyphicon-plus': minimized, 'glyphicon glyphicon-minus': !minimized}">-</button>
        <input ng-model="value.___KEY___" ng-if="!isArrayElement(value)" />
        <input ng-if="isLeaf(value)" ng-model="value.___VALUE___" />
        <ul ng-if="!isLeaf(value)" ng-show="!minimized">
            <li ng-repeat="(key,value) in value" ng-if="key != '___KEY___' && key != '___ISARRAY___'" ng-include="'node.html'"></li>
            <button type="button" ng-if="isArray(value)" ng-click="addToArray(value)">Add Element</button>
        </ul>
    </script>
</head>
<body ng-app="Application" ng-controller="jsoncrudctrl">
    <ul>
        <li ng-repeat="(key,value) in json" ng-include="'node.html'"></li>
    </ul>
    <pre>{{stringify(json)}}</pre>
</body>
</html>

One thing I would like to do is replace isArrayElement(value) with isArray(parent), because isArrayElement relies on meta data I added to the array, which I would prefer to not have to add.

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

ng-repeat creates a new scope for each element.
ng-include also creates a new scope.

When you use ng-include together with ng-repeat, there are 2 scopes created for each element:

  • Scope created by ng-repeat for current element. This scope holds the current element in the iteration.
  • Child scope created by ng-include which inherits from ng-repeat‘s created scope.

The $parent property of current scope allows you to access its parent scope.

Essentially, scope created by ng-include is empty, when you access value and key in your node.html, it actually access the inherited values from parent scope created by ng-repeat.

In your node.html, accessing {{value}} is actually the same as {{$parent.value}}. Therefore if you need to access the parent of the current element, you have to do one step further by accessing {{$parent.$parent.value}}

This DEMO will clear things up:

    <script type="text/ng-template" id="node.html">
        <div>
            Current: key = {{key}}, value = {{value}}
        </div>
        <div>
            Current (using $parent): key = {{$parent.key}}, value = {{$parent.value}}
        </div>
         <div>
             Parent: key = {{$parent.$parent.key}}, value = {{$parent.$parent.value}}, isArray: {{isArray($parent.$parent.value)}}
        </div>
        <ul ng-if="isObject(value)"> //only iterate over object to avoid problems when iterating a string
<li ng-repeat="(key,value) in value" ng-include="'node.html'"></li>            
        </ul>
    </script>

If you need to simplify the way to access the parent, you could try initializing the parent using onload of ng-include. Like this:

In your top level, there is no ng-if => only 2 level deep

<ul>
    <li ng-repeat="(key,value) in json" 
     ng-include="'node.html'" onload="parent=$parent.$parent"></li>
</ul>

In your sub levels, there is ng-if => 3 levels deep:

    <ul ng-if="isObject(value)">
        <li ng-repeat="(key,value) in value" 
ng-include="'node.html'" onload="parent=$parent.$parent.$parent"></li>            
    </ul>

Inside the template, you could access the parent using parent, grandparent using parent.parent and so on.

DEMO

Method 2

I would stay away from Angular’s $parent and all the $scope creation and inheritance madness. What you need is to keep a reference to the parent object, not finding how many scopes are in-between ng-include‘s and ng-repeat‘s and juggling with $parent.$parent. My suggestion is to explicitly save references to the values you are interested in, just implement it yourself with custom logic. For example, if you want to expose a value from the parent ng-repeat to the child ng-repeat

<!-- Explictly save the value into the parent var -->
<div ng-init="parent = value">
  <!-- Save parent reference and
       update the parent var to point to the new value -->
  <div ng-repeat="(k,value) in value"
       ng-init="value._parent = parent; parent = value;"> 
    <div ng-repeat="(k,value) in value"
         ng-init="value._parent = parent">
      <button ng-click="doSomething(value)"></button>
    </div>
  </div>
</div>

Then in your javascript code you can access all parents recursively

function doSomething(value){
  parent1 = value._parent;
  parent2 = parent1._parent;
}

Same code with ng-include

<div ng-init="parent = value">
  <div ng-repeat="(key,value) in value"
       ng-init="value._parent = parent; parent = value;"
       ng-include="'node.html'">
  </div>
</div>

<script type="text/ng-template" id="node.html">
  <div ng-if="!isLeaf(value)"
       ng-repeat="(key,value) in value"
       ng-init="value._parent = parent; parent = value;"
       ng-include="'node.html'"> 

  <button ng-if="isLeaf(value)" ng-click="doSomething(value)"></button>
</script>

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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