title: Change the style of the selected ng-repeat item and remove the other item's style
body: <p>I'm a freshman to AngularJS. I try to modify the item's style using AngularJS, but I meet this bug:
  when I select another item, the background of the first item is still blue. How to change my code to fix this?
  Here is my <a href="http://plnkr.co/edit/BAoyRUNF8MnmghXH0dym?p=preview" rel="nofollow">plnkr</a>.
  And here is the code.</p>
  
  <pre><code>&lt;div ng-init="selectedNode = false"&gt;
    &lt;div ng-repeat="item in items" ng-click="selectedNode=true" ng-class="{selected: selectedNode == true}"&gt;{{item.value}}&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>When I click on 2 after click on 1, the background color of 1 should be removed. It means only one item should be selected. How to slove this problem?</p>