angular nested component parent is undefined

Question

Does anyone know why if I try to get the parent straight in the controller I get undefined? If I use it inside a function it works nice.

var sidebar = {
  transclude: true,
  bindings: {
    isOpen: '='
  },
  controller: function () {
    function toggle() {
      //this.isOpen = !this.isOpen;
      console.log('my test');
    }
    this.toggle = toggle;
  },
  template: ['$element', '$attrs',function ($element, $attrs) {
    return [
    '<div class="sidebars" ng-transclude>',
    '</div>'
    ].join('');
  }]
};

var sidebarItem = {
  require: {
    parent: '^sidebar'
  },
  bindings: {
    header: '='
  },
  controller: function () {
    function mytest() {
      // this works
      console.log('isOpen is ',this.parent.isOpen);
      this.parent.toggle();
    }
    // here I got Parent is undefined
    console.log('Parent is ',this.parent);
    //this.parent.toggle();
    this.mytest = mytest;
  },
  template: ['$element', '$attrs',function ($element, $attrs) {
    return [
    '<div class="sidebar__item">',
      '<h3 ng-click="$ctrl.mytest();">{{$ctrl.header}}</span>',
      '<ul>',
      '<li>Test</li>',
      '</ul>',
    '</div>'
    ].join('');
  }]
};
angular.module('layout.directives', [])
  .component('sidebar', sidebar)
  .component('sidebarItem', sidebarItem);

Answer 1

If you wrap

console.log('Parent is ',this.parent);

with a $timeout, problem solved.

So, like this:

$timeout(function(){
    // here I got Parent is undefined
    console.log('Parent is ',this.parent);
})

It seems that the required component's controller is only available after digest cycle has completed. That's why it works when it is called from the template (in the mytest() function).