AngularJS Essentials

Because of this, the most recommended way to use the dependency injection
mechanism, despite verbosity, is through the inline array annotation, as follows:
parking.controller("parkingCtrl", ["$scope", "$filter", function
($scope, $filter) {
$scope.appTitle = $filter("uppercase")("[Packt] Parking");
}]);
This way, no matter what the name of each parameter is, the correct dependency
will be injected, resisting the most common algorithms that minify and obfuscate
the code.
Chapter 4
The dependencies can also be injected in the same way inside directives, filters, and
services. Later, in Chapter 7, Unit Testing, we are going to learn other strategies in
order to inject dependencies for testing purposes.
In the following sections, we are going to use these concepts in greater detail while
using and creating services.
Creating services
In AngularJS, a service is a singleton object that has its life cycle controlled by the
framework. It can be used by any other component such as controllers, directives,
filters, and even other services.
Now, it's time to evolve our application, introducing new features in order to
calculate the parking time and also the price.
To keep high levels of cohesion inside each component, we must take care of what
kind of behavior is implemented in the controller. This kind of feature could be the
responsibility of a service that can be shared across the entire application and also
tested separately.
In the following code, the controller is delegating a specific behavior to the service,
creating a place to evolve the business rules in the future:
controllers.js
parking.controller("parkingCtrl", function ($scope, parkingService) {
$scope.appTitle = "[Packt] Parking";
$scope.cars = [];
$scope.colors = ["White", "Black", "Blue", "Red", "Silver"];
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