$index restart each row in ng-repeat - arrays

Question

I want to repeat this code for each element in my array:
<div class="container" ng-init="parentIndex = $index" ng-repeat="urn in apsocket.mensajes | filter:searchTextURN">
<button style="width:100%" type="button" class="btn btn-info" data-toggle="collapse" data-target="{{'#urn_'+$index}}">{{urn.urn }}</button>
<div id="{{'urn_'+$index}}" class="collapse">
{{urn.timestamp}}
<br>
<p>
<div align="right" ng-repeat="meas in urn.measurements track by $index">
<button style="width:90%;background-color: #68ec6a;border-color:#8bf48c;" type="button" class="btn btn-success" data-toggle="collapse" data-target="{{'#meas_'+parentIndex + '_' +$index}}">{{meas.phenomenon}} </button>
<div style="width:90%" id="{{'meas_'+parentIndex + '_' +$index}}" class="collapse">
{{meas.value + ' ' + meas.uom}}
</div>
</div>
</p>
</div>
</div>
But, while first button in each row works fine and creates a working collapsible, the inner ng-repeats seem not.
Each inner element in each outter row, have the same id. So, for each "container", parentIndex is the same and starts in 0.
What should I do in this case? This is not a fixed array which I load at the beggining. This array recevies data from socket and it get bigger each time a message is received.
If you need any more code or so, just ask.

Answer 1

I would recommend just using the pure angular way. In a repeat, each item has it's own scope so you can do an ng-click="collapse = ! collapse" (something like that), I made you an example here
http://jsfiddle.net/X8era/82/
I just made a fake data structure for examples sake
<ul>
<li ng-repeat="item in objs" ng-click="collapse = ! collapse">
{{item.id}}
<ul ng-show="item.more.length > 0 && collapse">
<li ng-repeat="child in item.more" ng-click="collapse = ! collapse; $event.stopPropagation();" >
{{child.id}}
<ul ng-show="child.more.length > 0 && collapse">
<li ng-repeat="baby in child.more">
{{baby.id}}
</li>
</ul>
</li>
</ul>
</li>
</ul>
If you would like to use the collapse class for an animation or whatever, you can change the part of the ng-show that is collapse to
ng-class="{ 'collapse' : collapse }"
The first 'collapse' being whatever class you want to be toggled.

Answer 2

You don't have to use ng-init="parentIndex = $index". You can access to parent $index like this $parent.$index.
Each ng-repeat creates new scope, that's why you can access to parent by using $parent keyword.
Demo:
var app = angular.module('app',[]);
app.controller('ctrl', function($scope) {
$scope.items = [0, 1, 2, 3, 4];
});
<div ng-app="app" ng-controller="ctrl">
<ul>
<li ng-repeat="item in items track by $index">
<ul>
<li ng-repeat="item in items track by $index">
parent: {{$parent.$index}}
current: {{$index}}
</li>
</ul>
</li>
</ul>
</div>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>