angular.js/docs/content/tutorial/step_02.ngdoc

@ngdoc overview
@name Tutorial: 2 - Angular Templates
@description

<ul doc-tutorial-nav="2"></ul>


Now it's time to make the web page dynamic — with AngularJS. We'll also add a test that verifies the
code for the controller we are going to add.

There are many ways to structure the code for an application. For Angular apps, we encourage the
use of {@link http://en.wikipedia.org/wiki/Model–View–Controller the Model-View-Controller (MVC)
design pattern} to decouple the code and to separate concerns. With that in mind, let's use a
little Angular and JavaScript to add model, view, and controller components to our app.


<div doc-tutorial-reset="2"></div>


The app now contains a list with three phones.

The most important changes are listed below. You can see the full diff on {@link
https://github.com/angular/angular-phonecat/compare/step-1...step-2 GitHub}:


## View and Template

In Angular, the __view__ is a projection of the model through the HTML __template__. This means that
whenever the model changes, Angular refreshes the appropriate binding points, which updates the
view.

The view component is constructed by Angular from this template:

__`app/index.html`:__
<pre>
<html ng-app>
<head>
  ...
  <script src="lib/angular/angular.js"></script>
  <script src="js/controllers.js"></script>
</head>
<body ng-controller="PhoneListCtrl">

  <ul>
    <li ng-repeat="phone in phones">
      {{phone.name}}
      <p>{{phone.snippet}}</p>
    </li>
  </ul>
</body>
</html>
</pre>

We replaced the hard-coded phone list with the
{@link api/ng.directive:ngRepeat ngRepeat directive} and two
{@link guide/expression Angular expressions} enclosed in curly braces:
`{{phone.name}}` and `{{phone.snippet}}`:

* The `ng-repeat="phone in phones"` statement in the `<li>` tag is an Angular repeater. The
repeater tells Angular to create a `<li>` element for each phone in the list using the first `<li>`
tag as the template.

* As we've learned in step 0, the curly braces around `phone.name` and `phone.snippet` denote
bindings. As opposed to evaluating constants, these expressions are referring to our application
model, which was set up in our `PhoneListCtrl` controller.

      <img class="diagram" src="img/tutorial/tutorial_02.png">


## Model and Controller

The data __model__ (a simple array  of phones in object literal notation) is instantiated within
the `PhoneListCtrl` __controller__:

__`app/js/controllers.js`:__
<pre>
function PhoneListCtrl($scope) {
  $scope.phones = [
    {"name": "Nexus S",
     "snippet": "Fast just got faster with Nexus S."},
    {"name": "Motorola XOOM™ with Wi-Fi",
     "snippet": "The Next, Next Generation tablet."},
    {"name": "MOTOROLA XOOM™",
     "snippet": "The Next, Next Generation tablet."}
  ];
}
</pre>


Although the controller is not yet doing very much controlling, it is playing a crucial role. By
providing context for our data model, the controller allows us to establish data-binding between
the model and the view. We connected the dots between the presentation, data, and logic components
as follows:

* `PhoneListCtrl` — the name of our controller function (located in the JavaScript file
`controllers.js`), matches the value of the
{@link api/ng.directive:ngController ngController} directive located
on the `<body>` tag.

* The phone data is then attached to the *scope* (`$scope`) that was injected into our controller
function. The controller scope is a prototypical descendant of the root scope that was created
when the application bootstrapped. This controller scope is available to all bindings located within
the `<body ng-controller="PhoneListCtrl">` tag.

  The concept of a scope in Angular is crucial; a scope can be seen as the glue which allows the
template, model and controller to work together. Angular uses scopes, along with the information
contained in the template, data model, and controller, to keep models and views separate, but in
sync. Any changes made to the model are reflected in the view; any changes that occur in the view
are reflected in the model.

  To learn more about Angular scopes, see the {@link api/ng.$rootScope.Scope angular scope documentation}.


## Tests

The "Angular way" makes it easy to test code as it is being developed. Take a look at the following
unit test for your newly created controller:

__`test/unit/controllersSpec.js`:__
<pre>
describe('PhoneCat controllers', function() {

  describe('PhoneListCtrl', function(){

    it('should create "phones" model with 3 phones', function() {
      var scope = {},
          ctrl = new PhoneListCtrl(scope);

      expect(scope.phones.length).toBe(3);
    });
  });
});
</pre>

The test verifies that we have three records in the phones array and the example demonstrates how
easy it is to create a unit test for code in Angular. Since testing is such a critical part of
software development, we make it easy to create tests in Angular so that developers are encouraged
to write them.

Angular developers prefer the syntax of Jasmine's Behavior-driven Development  (BDD) framework when
writing tests. Although Angular does not require you to use Jasmine, we wrote all of the tests in
this tutorial in Jasmine. You can learn about Jasmine on the {@link
http://pivotal.github.com/jasmine/ Jasmine home page} and on the {@link
https://github.com/pivotal/jasmine/wiki Jasmine wiki}.

The angular-seed project is pre-configured to run all unit tests using {@link
http://code.google.com/p/js-test-driver/ JsTestDriver}. To run the test, do the following:

1. In a _separate_ terminal window or tab, go to the `angular-phonecat` directory and run
`./scripts/test-server.sh` to start the test web server.

2. Open a new browser window and navigate to {@link http://localhost:9876}.

3. Choose "Capture this browser in strict mode".

   At this point, you can leave this window open and forget about it. JsTestDriver will use it to
execute the tests and report the results in the terminal.

4. Execute the test by running `./scripts/test.sh`

   You should see the following or similar output:

             Chrome: Runner reset.
             .
             Total 1 tests (Passed: 1; Fails: 0; Errors: 0) (2.00 ms)
               Chrome 19.0.1084.36 Mac OS: Run 1 tests (Passed: 1; Fails: 0; Errors 0) (2.00 ms)

  Yay! The test passed! Or not...

  Note: If you see errors after you run the test, close the browser window and go back to the
  terminal and kill the script, then repeat the procedure above.

# Experiments

* Add another binding to `index.html`. For example:

          <p>Total number of phones: {{phones.length}}</p>

* Create a new model property in the controller and bind to it from the template. For example:

          $scope.hello = "Hello, World!"

  Refresh your browser to make sure it says, "Hello, World!"

* Create a repeater that constructs a simple table:

          <table>
            <tr><th>row number</th></tr>
            <tr ng-repeat="i in [0, 1, 2, 3, 4, 5, 6, 7]"><td>{{i}}</td></tr>
          </table>

  Now, make the list 1-based by incrementing `i` by one in the binding:

          <table>
            <tr><th>row number</th></tr>
            <tr ng-repeat="i in [0, 1, 2, 3, 4, 5, 6, 7]"><td>{{i+1}}</td></tr>
          </table>

* Make the unit test fail by changing the `toBe(3)` statement to `toBe(4)`, and rerun the
`./scripts/test.sh` script.


# Summary

You now have a dynamic app that features separate model, view, and controller components, and you
are testing as you go. Now, let's go to {@link step_03 step 3} to learn how to add full text search
to the app.


<ul doc-tutorial-nav="2"></ul>
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								@ngdoc overview
 								@name Tutorial: 2 - Angular Templates
 								@description
-												chore(docs): re-skin main documentation

											
										
										
											2012-04-29 05:45:28 +00:00
+								<ul doc-tutorial-nav="2"></ul>
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								Now it's time to make the web page dynamic — with AngularJS. We'll also add a test that verifies the
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								code for the controller we are going to add.
 								There are many ways to structure the code for an application. For Angular apps, we encourage the
 								use of {@link http://en.wikipedia.org/wiki/Model–View–Controller the Model-View-Controller (MVC)
 								design pattern} to decouple the code and to separate concerns. With that in mind, let's use a
 								little Angular and JavaScript to add model, view, and controller components to our app.
-												chore(docs): re-skin main documentation

											
										
										
											2012-04-29 05:45:28 +00:00
+								<div doc-tutorial-reset="2"></div>
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								The app now contains a list with three phones.
 								The most important changes are listed below. You can see the full diff on {@link
 								https://github.com/angular/angular-phonecat/compare/step-1...step-2 GitHub}:
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								## View and Template
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								In Angular, the __view__ is a projection of the model through the HTML __template__. This means that
 								whenever the model changes, Angular refreshes the appropriate binding points, which updates the
 								view.
 								The view component is constructed by Angular from this template:
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								__`app/index.html`:__
 								<pre>
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								<html ng-app>
 								<head>
 								  ...
 								  <script src="lib/angular/angular.js"></script>
 								  <script src="js/controllers.js"></script>
 								</head>
 								<body ng-controller="PhoneListCtrl">
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								  <ul>
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								    <li ng-repeat="phone in phones">
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								      {{phone.name}}
 								      <p>{{phone.snippet}}</p>
 								    </li>
 								  </ul>
 								</body>
 								</html>
 								</pre>
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								We replaced the hard-coded phone list with the
-												docs(*): simplify doc urls

we now have two types of namespaces:

- true namespace: angular.* - used for all global apis
- virtual namespace: ng.*, ngMock.*, ... - used for all DI modules

the virual namespaces have services under the second namespace level (e.g. ng.)
and filters and directives prefixed with filter: and directive: respectively
(e.g. ng.filter:orderBy, ng.directive:ngRepeat)

this simplifies urls and makes them a lot shorter while still avoiding name collisions

											
										
										
											2012-06-12 06:49:24 +00:00
+								{@link api/ng.directive:ngRepeat ngRepeat directive} and two
-												doc(guide): clean up broken links

											
										
										
											2012-05-24 21:49:47 +00:00
+								{@link guide/expression Angular expressions} enclosed in curly braces:
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								`{{phone.name}}` and `{{phone.snippet}}`:
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								* The `ng-repeat="phone in phones"` statement in the `<li>` tag is an Angular repeater. The
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								repeater tells Angular to create a `<li>` element for each phone in the list using the first `<li>`
 								tag as the template.
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								* As we've learned in step 0, the curly braces around `phone.name` and `phone.snippet` denote
-												docs(module): fixed module example and corrected typos

											
										
										
											2012-09-05 14:28:42 +00:00
+								bindings. As opposed to evaluating constants, these expressions are referring to our application
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								model, which was set up in our `PhoneListCtrl` controller.
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
-												chore(docs): re-skin main documentation

											
										
										
											2012-04-29 05:45:28 +00:00
+								      <img class="diagram" src="img/tutorial/tutorial_02.png">
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								## Model and Controller
 								The data __model__ (a simple array  of phones in object literal notation) is instantiated within
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								the `PhoneListCtrl` __controller__:
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								__`app/js/controllers.js`:__
 								<pre>
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								function PhoneListCtrl($scope) {
-												docs(tutorial): update all the remaining steps

I made some diagrams and portions of the text that are stil stale
invisible. We'll fix these in the next relese.

											
										
										
											2012-04-27 22:18:54 +00:00
+								  $scope.phones = [
 								    {"name": "Nexus S",
 								     "snippet": "Fast just got faster with Nexus S."},
 								    {"name": "Motorola XOOM™ with Wi-Fi",
 								     "snippet": "The Next, Next Generation tablet."},
 								    {"name": "MOTOROLA XOOM™",
 								     "snippet": "The Next, Next Generation tablet."}
 								  ];
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								}
 								</pre>
 								Although the controller is not yet doing very much controlling, it is playing a crucial role. By
 								providing context for our data model, the controller allows us to establish data-binding between
 								the model and the view. We connected the dots between the presentation, data, and logic components
 								as follows:
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								* `PhoneListCtrl` — the name of our controller function (located in the JavaScript file
 								`controllers.js`), matches the value of the
-												docs(*): simplify doc urls

we now have two types of namespaces:

- true namespace: angular.* - used for all global apis
- virtual namespace: ng.*, ngMock.*, ... - used for all DI modules

the virual namespaces have services under the second namespace level (e.g. ng.)
and filters and directives prefixed with filter: and directive: respectively
(e.g. ng.filter:orderBy, ng.directive:ngRepeat)

this simplifies urls and makes them a lot shorter while still avoiding name collisions

											
										
										
											2012-06-12 06:49:24 +00:00
+								{@link api/ng.directive:ngController ngController} directive located
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								on the `<body>` tag.
 								* The phone data is then attached to the *scope* (`$scope`) that was injected into our controller
-												fix(docs): Adjectve accidentally made into an adverb

											
										
										
											2012-07-18 19:00:45 +00:00
+								function. The controller scope is a prototypical descendant of the root scope that was created
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								when the application bootstrapped. This controller scope is available to all bindings located within
 								the `<body ng-controller="PhoneListCtrl">` tag.
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								  The concept of a scope in Angular is crucial; a scope can be seen as the glue which allows the
 								template, model and controller to work together. Angular uses scopes, along with the information
 								contained in the template, data model, and controller, to keep models and views separate, but in
 								sync. Any changes made to the model are reflected in the view; any changes that occur in the view
 								are reflected in the model.
-												docs(*): simplify doc urls

we now have two types of namespaces:

- true namespace: angular.* - used for all global apis
- virtual namespace: ng.*, ngMock.*, ... - used for all DI modules

the virual namespaces have services under the second namespace level (e.g. ng.)
and filters and directives prefixed with filter: and directive: respectively
(e.g. ng.filter:orderBy, ng.directive:ngRepeat)

this simplifies urls and makes them a lot shorter while still avoiding name collisions

											
										
										
											2012-06-12 06:49:24 +00:00
+								  To learn more about Angular scopes, see the {@link api/ng.$rootScope.Scope angular scope documentation}.
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								## Tests
 								The "Angular way" makes it easy to test code as it is being developed. Take a look at the following
 								unit test for your newly created controller:
 								__`test/unit/controllersSpec.js`:__
 								<pre>
 								describe('PhoneCat controllers', function() {
-												docs(tutorial): update all the remaining steps

I made some diagrams and portions of the text that are stil stale
invisible. We'll fix these in the next relese.

											
										
										
											2012-04-27 22:18:54 +00:00
+								  describe('PhoneListCtrl', function(){
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								    it('should create "phones" model with 3 phones', function() {
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								      var scope = {},
 								          ctrl = new PhoneListCtrl(scope);
 								      expect(scope.phones.length).toBe(3);
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								    });
 								  });
 								});
 								</pre>
 								The test verifies that we have three records in the phones array and the example demonstrates how
 								easy it is to create a unit test for code in Angular. Since testing is such a critical part of
 								software development, we make it easy to create tests in Angular so that developers are encouraged
 								to write them.
 								Angular developers prefer the syntax of Jasmine's Behavior-driven Development  (BDD) framework when
 								writing tests. Although Angular does not require you to use Jasmine, we wrote all of the tests in
 								this tutorial in Jasmine. You can learn about Jasmine on the {@link
 								http://pivotal.github.com/jasmine/ Jasmine home page} and on the {@link
 								https://github.com/pivotal/jasmine/wiki Jasmine wiki}.
 								The angular-seed project is pre-configured to run all unit tests using {@link
 								http://code.google.com/p/js-test-driver/ JsTestDriver}. To run the test, do the following:
 . In a _separate_ terminal window or tab, go to the `angular-phonecat` directory and run
 								`./scripts/test-server.sh` to start the test web server.
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+. Open a new browser window and navigate to {@link http://localhost:9876}.
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 . Choose "Capture this browser in strict mode".
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								   At this point, you can leave this window open and forget about it. JsTestDriver will use it to
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								execute the tests and report the results in the terminal.
 . Execute the test by running `./scripts/test.sh`
 								   You should see the following or similar output:
 								             Chrome: Runner reset.
 								             .
 								             Total 1 tests (Passed: 1; Fails: 0; Errors: 0) (2.00 ms)
-												docs(tutorial): update all the remaining steps

I made some diagrams and portions of the text that are stil stale
invisible. We'll fix these in the next relese.

											
										
										
											2012-04-27 22:18:54 +00:00
+								               Chrome 19.0.1084.36 Mac OS: Run 1 tests (Passed: 1; Fails: 0; Errors 0) (2.00 ms)
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								  Yay! The test passed! Or not...
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								  Note: If you see errors after you run the test, close the browser window and go back to the
 								  terminal and kill the script, then repeat the procedure above.
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								# Experiments
 								* Add another binding to `index.html`. For example:
 								          <p>Total number of phones: {{phones.length}}</p>
 								* Create a new model property in the controller and bind to it from the template. For example:
-												docs(tutorial): fix typos in steps 2 and 3

											
										
										
											2012-04-10 13:04:13 +00:00
+								          $scope.hello = "Hello, World!"
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
 								  Refresh your browser to make sure it says, "Hello, World!"
 								* Create a repeater that constructs a simple table:
 								          <table>
 								            <tr><th>row number</th></tr>
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								            <tr ng-repeat="i in [0, 1, 2, 3, 4, 5, 6, 7]"><td>{{i}}</td></tr>
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								          </table>
 								  Now, make the list 1-based by incrementing `i` by one in the binding:
 								          <table>
 								            <tr><th>row number</th></tr>
-												docs(tutorial): update tutorial intro + steps 0-3

also contains all kinds of fixes that I had to make in the docs app to
get the tutorial to render correctly

											
										
										
											2012-04-02 15:32:30 +00:00
+								            <tr ng-repeat="i in [0, 1, 2, 3, 4, 5, 6, 7]"><td>{{i+1}}</td></tr>
-												chore(docs): restore old tutorial ngdoc files

											
										
										
											2012-03-30 21:02:26 +00:00
+								          </table>
 								* Make the unit test fail by changing the `toBe(3)` statement to `toBe(4)`, and rerun the
 								`./scripts/test.sh` script.
 								# Summary
 								You now have a dynamic app that features separate model, view, and controller components, and you
 								are testing as you go. Now, let's go to {@link step_03 step 3} to learn how to add full text search
 								to the app.
-												chore(docs): re-skin main documentation

											
										
										
											2012-04-29 05:45:28 +00:00
+								<ul doc-tutorial-nav="2"></ul>