1 <h1 id="lab_3_model_view_controller">Create MVC</h1>
3 <p>Whenever your application grows beyond a single script with a few dozen lines,
4 it gets harder and harder to manage without a good separation
5 of roles among app components.
6 One of the most common models for structuring a complex application,
7 no matter what language,
8 is the Model-View-Controller (MVC) and its variants,
9 like Model-View-Presentation (MVP).</p>
11 <p>There are several frameworks to help apply
12 <a href="app_frameworks.html">MVC concepts</a>
13 to a Javascript application, and most of them,
14 as long as they are CSP compliant, can be used in a Chrome App.
16 we'll add an MVC model using both pure JavaScript and
17 the <a href="http://angularjs.org/">AngularJS</a> framework.
18 Most of the AngularJS code from this section was copied,
19 with small changes, from the AngularJS Todo tutorial.</p>
21 <p class="note"><b>Note:</b>
22 Chrome Apps don't enforce any specific framework or programming style.
25 <h2 id="simple">Create a simple view</h2>
27 <h3 id="basic-mvc">Add MVC basics</h3>
29 <p>If using AngularJS, download the
30 <a href="http://ajax.googleapis.com/ajax/libs/angularjs/1.0.2/angular.min.js">Angular script</a>
32 <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/angularjs/simpleview/angular.min.js">angular.min.js</a>.</p>
34 <p>If using JavaScript,
35 you will need to add a very simple controller with basic MVC functionalities:
36 <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/javascript/simpleview/controller.js">JavaScript controller.js</a></p>
38 <h3 id="update-view">Update view</h3>
40 <p>Change the <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/angularjs/simpleview/index.html">AngularJS index.html</a> or
41 <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/javascript/simpleview/index.html">JavaScript index.html</a> to use a simple sample:
44 <tabs data-group="source">
46 <header tabindex="0" data-value="angular">Angular</header>
47 <header tabindex="0" data-value="js">JavaScript</header>
50 <pre data-filename="index.html">
52 <html ng-app ng-csp>
54 <script src="angular.min.js"></script>
55 <link rel="stylesheet" href="todo.css">
58 <h2>Todo</h2>
62 {{todoText}}
65 <input type="text" ng-model="todoText" size="30"
66 placeholder="type your todo here">
73 <pre data-filename="index.html">
77 <link rel="stylesheet" href="todo.css">
80 <h2>Todo</h2>
83 <li id="todoText">
86 <input type="text" id="newTodo" size="30"
87 placeholder="type your todo here">
89 <script src="controller.js"></script>
96 <p class="note"><b>Note:</b> The <code>ng-csp</code> directive tells Angular to run in a "content security mode". You don't need this directive when using Angular v1.1.0+. We've included it here so that the sample works regardless of the Angular version in use.</p>
98 <h3 id="stylesheet">Add stylesheet</h3>
100 <p><a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/angularjs/simpleview/todo.css">AngularJS todo.css</a> and
101 <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/javascript/simpleview/todo.css">JavaScript todo.css</a> are the same:
104 <pre data-filename="todo.css">
106 font-family: "Helvetica Neue",Helvetica,Arial,sans-serif;
113 button, input[type=submit] {
114 background-color: #0074CC;
115 background-image: linear-gradient(top, #08C, #05C);
116 border-color: rgba(0, 0, 0, 0.1) rgba(0, 0, 0, 0.1) rgba(0, 0, 0, 0.25);
117 text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.25);
122 text-decoration: line-through;
127 <h3 id="check1">Check the results</h3>
130 Check the results by reloading the app: open the app, right-click and select Reload App.</li>
133 <h2 id="real-todo">Create real Todo list</h2>
136 The previous sample, although interesting, is not exactly useful.
137 Let's transform it into a real Todo list, instead of a simple Todo item.
140 <h3 id="controller">Add controller</h3>
143 Whether using pure JavaScript or AngularJS,
144 the controller manages the Todo list:
145 <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/angularjs/withcontroller/controller.js">AngularJS controller.js</a> or
146 <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/javascript/withcontroller/controller.js">JavaScript controller.js</a>.
149 <tabs data-group="source">
151 <header tabindex="0" data-value="angular">Angular</header>
152 <header tabindex="0" data-value="js">JavaScript</header>
155 <pre data-filename="controller.js">
156 function TodoCtrl($scope) {
158 {text:'learn angular', done:true},
159 {text:'build an angular Chrome packaged app', done:false}];
161 $scope.addTodo = function() {
162 $scope.todos.push({text:$scope.todoText, done:false});
163 $scope.todoText = '';
166 $scope.remaining = function() {
168 angular.forEach($scope.todos, function(todo) {
169 count += todo.done ? 0 : 1;
174 $scope.archive = function() {
175 var oldTodos = $scope.todos;
177 angular.forEach(oldTodos, function(todo) {
178 if (!todo.done) $scope.todos.push(todo);
185 <pre data-filename="controller.js">
190 var TodoModel = function() {
195 TodoModel.prototype.clearTodos = function() {
197 this.notifyListeners('removed');
200 TodoModel.prototype.archiveDone = function() {
201 var oldTodos = this.todos;
203 for (var id in oldTodos) {
204 if ( ! oldTodos[id].isDone ) {
205 this.todos[id] = oldTodos[id];
208 this.notifyListeners('archived');
211 TodoModel.prototype.setTodoState = function(id, isDone) {
212 if ( this.todos[id].isDone != isDone ) {
213 this.todos[id].isDone = isDone;
214 this.notifyListeners('stateChanged', id);
218 TodoModel.prototype.addTodo = function(text, isDone) {
220 this.todos[id]={'id': id, 'text': text, 'isDone': isDone};
221 this.notifyListeners('added', id);
224 TodoModel.prototype.addListener = function(listener) {
225 this.listeners.push(listener);
228 TodoModel.prototype.notifyListeners = function(change, param) {
230 this.listeners.forEach(function(listener) {
231 listener(this_, change, param);
235 exports.TodoModel = TodoModel;
240 window.addEventListener('DOMContentLoaded', function() {
242 var model = new TodoModel();
243 var form = document.querySelector('form');
244 var archive = document.getElementById('archive');
245 var list = document.getElementById('list');
246 var todoTemplate = document.querySelector('#templates > [data-name="list"]');
248 form.addEventListener('submit', function(e) {
249 var textEl = e.target.querySelector('input[type="text"]');
250 model.addTodo(textEl.value, false);
255 archive.addEventListener('click', function(e) {
260 model.addListener(function(model, changeType, param) {
261 if ( changeType === 'removed' || changeType === 'archived') {
263 } else if ( changeType === 'added' ) {
264 drawTodo(model.todos[param], list);
265 } else if ( changeType === 'stateChanged') {
266 updateTodo(model.todos[param]);
268 updateCounters(model);
271 var redrawUI = function(model) {
273 for (var id in model.todos) {
274 drawTodo(model.todos[id], list);
278 var drawTodo = function(todoObj, container) {
279 var el = todoTemplate.cloneNode(true);
280 el.setAttribute('data-id', todoObj.id);
281 container.appendChild(el);
283 var checkbox = el.querySelector('input[type="checkbox"]');
284 checkbox.addEventListener('change', function(e) {
285 model.setTodoState(todoObj.id, e.target.checked);
289 var updateTodo = function(model) {
290 var todoElement = list.querySelector('li[data-id="'+model.id+'"]');
292 var checkbox = todoElement.querySelector('input[type="checkbox"]');
293 var desc = todoElement.querySelector('span');
294 checkbox.checked = model.isDone;
295 desc.innerText = model.text;
296 desc.className = "done-"+model.isDone;
300 var updateCounters = function(model) {
303 for (var id in model.todos) {
305 if ( ! model.todos[id].isDone ) {
309 document.getElementById('remaining').innerText = notDone;
310 document.getElementById('length').innerText = count;
313 updateCounters(model);
320 <h3 id="index">Update view</h3>
322 <p>Change the <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/angularjs/withcontroller/index.html">AngularJS index.html</a> or
323 <a href="https://github.com/GoogleChrome/chrome-app-codelab/blob/master/lab3_mvc/javascript/withcontroller/index.html">JavaScript index.html</a>:
326 <tabs data-group="source">
328 <header tabindex="0" data-value="angular">Angular</header>
329 <header tabindex="0" data-value="js">JavaScript</header>
332 <pre data-filename="index.html">
333 <html ng-app ng-csp>
335 <script src="angular.min.js"></script>
336 <script src="controller.js"></script>
337 <link rel="stylesheet" href="todo.css">
340 <h2>Todo</h2>
341 <div ng-controller="TodoCtrl">
342 <span>{{remaining()}} of {{todos.length}} remaining</span>
343 [ <a href="" ng-click="archive()">archive</a> ]
345 <li ng-repeat="todo in todos">
346 <input type="checkbox" ng-model="todo.done">
347 <span class="done-{{todo.done}}">{{todo.text}}</span>
350 <form ng-submit="addTodo()">
351 <input type="text" ng-model="todoText" size="30"
352 placeholder="add new todo here">
353 <input class="btn-primary" type="submit" value="add">
361 <pre data-filename="index.html">
362 <!doctype html>
365 <link rel="stylesheet" href="todo.css">
368 <h2>Todo</h2>
370 <span><span id="remaining"></span> of <span id="length"></span> remaining</span>
371 [ <a href="" id="archive">archive</a> ]
372 <ul class="unstyled" id="list">
375 <input type="text" size="30"
376 placeholder="add new todo here">
377 <input class="btn-primary" type="submit" value="add">
381 <!-- poor man's template -->
382 <div id="templates" style="display: none;">
383 <li data-name="list">
384 <input type="checkbox">
385 <span></span>
389 <script src="controller.js"></script>
396 <p>Note how the data, stored in an array inside the controller, binds to the view and is automatically updated when it is changed by the controller.</p>
398 <h3 id="check2">Check the results</h3>
401 Check the results by reloading the app: open the app, right-click and select Reload App.</li>
404 <h2 id="takeaways_">Takeaways</h2>
407 <li><p>Chrome Apps are
408 <a href="offline_apps.html">offline first</a>,
409 so the recommended way to include third-party scripts is to download
410 and package them inside your app.</p></li>
411 <li><p>You can use any framework you want,
412 as long as it complies with Content Security Policies
413 and other restrictions that Chrome Apps are enforced to follow.</p></li>
414 <li><p>MVC frameworks make your life easier.
415 Use them, specially if you want to build a non-trivial application.</p></li>
418 <h2 id="you_should_also_read">You should also read</h2>
421 <li><p><a href="angular_framework.html">Build Apps with AngularJS</a> tutorial</p></li>
422 <li><p><a href="http://angularjs.org/">AngularJS Todo</a> tutorial</p></li>
425 <h2 id="what_39_s_next_">What's next?</h2>
427 <p>In <a href="app_codelab5_data.html">4 - Save and Fetch Data</a>,
428 you will modify your Todo list app so that Todo items are saved.</p>