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<div ng-app="example">
    <div ng-controller="controller">
      <input type="button" value="Disable" ng-click="editorDIsabled=true">
      <input type="button" value="Enable" ng-click="editorDIsabled=false">
      <hr>
      
      <ng-ckeditor 
              ng-model="htmlEditor" 
              ng-disabled="editorDIsabled" 
              skin="moono" 
              remove-buttons="Image" 
              remove-plugins="iframe,flash,smiley">
      </ng-ckeditor>
      
      <hr>
      |{{htmlEditor}}|
    </div>
</div>

angular.module('example', ["ng.ckeditor"]).controller('controller', ['$scope', function($scope) {
  $scope.htmlEditor = '...';
}]);