Question

While building an application using AngularJs I asked my self if the following is good practice

I have “AppController” and every other controller is child of it. AppController has something like this.

$scope.layout = { sidebar: false, searchbar: true};

Now, child controllers should be able to change these values:

$rootScope.sidebar = true; 

In this case, my child module is totally dependent on root controller and if I want this child controller works inside some other application I have to make sure parent controller of that other app always have $scope.layout object. Is this good practice? Would it be better to build layout module used by both, parent and child controllers? Like code bellow:

angular.module("app.ui", [])
  .factory("Layout", [function(){
     var _sidebar = false;
     var searchbar = true;


     var sidebar = function(flag){
        if(flag !== undefined) _sidebar = flag;
        return _sidebar;
     }

     var searchbar = function(flag){
        if(flag !== undefined) _searchbar = flag;
        return _searchbar;
     }

return {
   sidebar : sidebar,
   searchbar : searchbar
}
}])

Answer 1

Whilst there may be other architectural approaches to what you want to do (e.g. look into the documentation on the scope property of directive declarations and its facilities for binding specific properties in the parent scope using @, = and &), generally Services are indeed a good option for sharing access to common data. You could simplify it a bit, if you don’t have extra logic that must happen when the values are updated:

angular.module("app.ui", [])

.service("Layout", function() {
  this.sidebar = false;
  this.searchbar = true;
})

If you inject this service into your controllers and add it to their scope, you can update it and listen for changes like this:

.controller("AppCtl", function($scope, Layout) {
  $scope.Layout = Layout;

  // Method called by a search button, say
  $scope.search = function() {
    Layout.searchbar = true;
  }

  $scope.$watch("Layout.searchbar", function(newVal, oldVal) {
    // Do something in this scope if value has been changed from elsewhere
  });

});