[angularjs] How can I use the $index inside a ng-repeat to enable a class and show a DIV?

I have a set of <li> elements.

<ul>
  <li ng-class="{current: selected == 100}">
     <a href ng:click="selected=100">ABC</a>
  </li>
  <li ng-class="{current: selected == 101}">
     <a href ng:click="selected=101">DEF</a>
  </li>
  <li ng-class="{current: selected == $index }" 
      ng-repeat="x in [4,5,6,7]">
     <a href ng:click="selected=$index">A{{$index}}</a>
  </li>
</ul>

When a user clicks on one of the address elements above then then it should, set the value of selected and show one of the <DIV> elements below:

<div  ng:show="selected == 100">100</div>
<div  ng:show="selected == 101">101</div>
<div ng-repeat="x in [4,5,6,7]" ng:show="selected == $index">{{ $index }}</div>

This works for the first two cases.

• When the user clicks ABC then the first <DIV> shows 100 and changes color to red.
• When DEF is clicked then 101 shows and DEF changes to red.

However it does not work at all for A0, A1, A2 and A3

• When a user clicks A0, A1, A2 or A3 then the correct does not show, the selected value is not set and the color of ALL the ng-repeat A0,A1,A2 and A3 turn to red.

This is best shown if you look at this Plunker:

http://plnkr.co/edit/7HMeObplaBkx5R0SntjY?p=preview

Note that at the top I have added {{ selected }} as a debug aid at the top. Also the x in [4,5,6,7] are just meant to simulate a loop. In real life I have this as ng-repeat="answer in modal.data.answers".

Does anyone know how I can set this up so that the li class current is set at the right time and the DIV shows at the right time for the A0, A1, A2 and A3 <li> and <DIV>

As johnnyynnoj mentioned ng-repeat creates a new scope. I would in fact use a function to set the value. See plunker

JS:

$scope.setSelected = function(selected) {
  $scope.selected = selected;
}

HTML:

{{ selected }}

<ul>
  <li ng-class="{current: selected == 100}">
     <a href ng:click="setSelected(100)">ABC</a>
  </li>
  <li ng-class="{current: selected == 101}">
     <a href ng:click="setSelected(101)">DEF</a>
  </li>
  <li ng-class="{current: selected == $index }" 
      ng-repeat="x in [4,5,6,7]">
     <a href ng:click="setSelected($index)">A{{$index}}</a>
  </li>
</ul>

<div  
  ng:show="selected == 100">
  100        
</div>
<div  
  ng:show="selected == 101">
  101        
</div>
<div ng-repeat="x in [4,5,6,7]" 
  ng:show="selected == $index">
  {{ $index }}        
</div>