summaryrefslogtreecommitdiffhomepage
path: root/angularjs.html.markdown
blob: 89afa2919958c4652fef5b1a4788354654483748 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
---
category: tool
tool: AngularJS
contributors:
    - ["Walter Cordero", "http://waltercordero.com"]
filename: learnangular.html
---

## AngularJS Tutorial.

AngularJS version 1.0 was released in 2012.
Miško Hevery, a Google employee, started to work with AngularJS in 2009.
The idea turned out very well, and the project is now officially supported by Google.

AngularJS is a JavaScript framework. It can be added to an HTML page with a "script" tag.
AngularJS extends HTML attributes with Directives, and binds data to HTML with Expressions.

##What You Should Already Know

Before you study AngularJS, you should have a basic understanding of:

- HTML
- CSS
- JavaScript

```html
// AngularJS is a JavaScript framework. It is a library written in JavaScript.
// AngularJS is distributed as a JavaScript file, and can be added to a web page with a script tag:
// <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>

///////////////////////////////////
// AngularJS Extends HTML

//AngularJS extends HTML with ng-directives.
//The ng-app directive defines an AngularJS application.
//The ng-model directive binds the value of HTML controls (input, select, textarea) to application data.
//The ng-bind directive binds application data to the HTML view.
<!DOCTYPE html>
<html>
  <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
  <body>
    <div ng-app="">
      <p>Name: <input type="text" ng-model="name"></p>
      <p ng-bind="name"></p>
    </div>
  </body>
</html>

/*
  * Example explained:
  * AngularJS starts automatically when the web page has loaded.
  * The ng-app directive tells AngularJS that the <div> element is the "owner" of an AngularJS application.
  * The ng-model directive binds the value of the input field to the application variable name.
  * The ng-bind directive binds the innerHTML of the <p> element to the application variable name.
*/
<tag> Here are content to be intrepreted </tag>

///////////////////////////////////
// AngularJS Expressions

// AngularJS expressions are written inside double braces: {{ expression }}.
// AngularJS expressions binds data to HTML the same way as the ng-bind directive.
// AngularJS will "output" data exactly where the expression is written.
// AngularJS expressions are much like JavaScript expressions: They can contain literals, operators, and variables.
// Example {{ 5 + 5 }} or {{ firstName + " " + lastName }}
<!DOCTYPE html>
<html>
  <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
  <body>
    <div ng-app="">
      <p>My first expression: {{ 5 + 5 }}</p>
    </div>
  </body>
</html>

//If you remove the ng-app directive, HTML will display the expression as it is, without solving it:
<!DOCTYPE html>
<html>
  <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
  <body>
    <div>
      <p>My first expression: {{ 5 + 5 }}</p>
    </div>
  </body>
</html>

// AngularJS expressions bind AngularJS data to HTML the same way as the ng-bind directive.
<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
  <body>
    <div ng-app="">
      <p>Name: <input type="text" ng-model="name"></p>
      <p>{{name}}</p>
    </div>
  </body>
</html>

// AngularJS numbers are like JavaScript numbers:
<div ng-app="" ng-init="quantity=1;cost=5">
  <p>Total in dollar: {{ quantity * cost }}</p>
</div>

//AngularJS strings are like JavaScript strings:
<div ng-app="" ng-init="firstName='John';lastName='Doe'">
  <p>The name is <span ng-bind="firstName + ' ' + lastName"></span></p>
</div>

//AngularJS objects are like JavaScript objects:
<div ng-app="" ng-init="person={firstName:'John',lastName:'Doe'}">
  <p>The name is {{ person.lastName }}</p>
</div>

//AngularJS arrays are like JavaScript arrays:
<div ng-app="" ng-init="points=[1,15,19,2,40]">
  <p>The third result is {{ points[2] }}</p>
</div>

// Like JavaScript expressions, AngularJS expressions can contain literals, operators, and variables.
// Unlike JavaScript expressions, AngularJS expressions can be written inside HTML.
// AngularJS expressions do not support conditionals, loops, and exceptions, while JavaScript expressions do.
// AngularJS expressions support filters, while JavaScript expressions do not.

///////////////////////////////////
// AngularJS Directives


//AngularJS directives are extended HTML attributes with the prefix ng-.
//The ng-app directive initializes an AngularJS application.
//The ng-init directive initializes application data.
//The ng-model directive binds the value of HTML controls (input, select, textarea) to application data.
<div ng-app="" ng-init="firstName='John'">
  <p>Name: <input type="text" ng-model="firstName"></p>
  <p>You wrote: {{ firstName }}</p>
</div>

//Using ng-init is not very common. You will learn how to initialize data in the chapter about controllers.

//The ng-repeat directive repeats an HTML element:
<div ng-app="" ng-init="names=['Jani','Hege','Kai']">
  <ul>
    <li ng-repeat="x in names">
      {{ x }}
    </li>
  </ul>
</div>

//The ng-repeat directive used on an array of objects:
<div ng-app="" ng-init="names=[
{name:'Jani',country:'Norway'},
{name:'Hege',country:'Sweden'},
{name:'Kai',country:'Denmark'}]">
  <ul>
    <li ng-repeat="x  in names">
      {{ x.name + ', ' + x.country }}
    </li>
  </ul>
</div>

// AngularJS is perfect for database CRUD (Create Read Update Delete) applications.
// Just imagine if these objects were records from a database.

// The ng-app directive defines the root element of an AngularJS application.
// The ng-app directive will auto-bootstrap (automatically initialize) the application when a web page is loaded.
// Later you will learn how ng-app can have a value (like ng-app="myModule"), to connect code modules.

// The ng-init directive defines initial values for an AngularJS application.
// Normally, you will not use ng-init. You will use a controller or module instead.
// You will learn more about controllers and modules later.

//The ng-model directive binds the value of HTML controls (input, select, textarea) to application data.
//The ng-model directive can also:
//Provide type validation for application data (number, email, required).
//Provide status for application data (invalid, dirty, touched, error).
//Provide CSS classes for HTML elements.
//Bind HTML elements to HTML forms.

//The ng-repeat directive clones HTML elements once for each item in a collection (in an array).

///////////////////////////////////
// AngularJS Controllers

// AngularJS controllers control the data of AngularJS applications.
// AngularJS controllers are regular JavaScript Objects.

// AngularJS applications are controlled by controllers.
// The ng-controller directive defines the application controller.
// A controller is a JavaScript Object, created by a standard JavaScript object constructor.

<div ng-app="myApp" ng-controller="myCtrl">

First Name: <input type="text" ng-model="firstName"><br>
Last Name: <input type="text" ng-model="lastName"><br>
<br>
Full Name: {{firstName + " " + lastName}}

</div>

<script>
var app = angular.module('myApp', []);
app.controller('myCtrl', function($scope) {
    $scope.firstName = "John";
    $scope.lastName = "Doe";
});
</script>

//Application explained:

//The AngularJS application is defined by  ng-app="myApp". The application runs inside the <div>.
//The ng-controller="myCtrl" attribute is an AngularJS directive. It defines a controller.
//The myCtrl function is a JavaScript function.
//AngularJS will invoke the controller with a $scope object.
//In AngularJS, $scope is the application object (the owner of application variables and functions).
//The controller creates two properties (variables) in the scope (firstName and lastName).
//The ng-model directives bind the input fields to the controller properties (firstName and lastName).

//The example above demonstrated a controller object with two properties: lastName and firstName.
//A controller can also have methods (variables as functions):
<div ng-app="myApp" ng-controller="personCtrl">

First Name: <input type="text" ng-model="firstName"><br>
Last Name: <input type="text" ng-model="lastName"><br>
<br>
Full Name: {{fullName()}}

</div>

<script>
var app = angular.module('myApp', []);
app.controller('personCtrl', function($scope) {
    $scope.firstName = "John";
    $scope.lastName = "Doe";
    $scope.fullName = function() {
        return $scope.firstName + " " + $scope.lastName;
    }
});
</script>

//In larger applications, it is common to store controllers in external files.
//Just copy the code between the <script> </script> tags into an external file named personController.js:

<div ng-app="myApp" ng-controller="personCtrl">

First Name: <input type="text" ng-model="firstName"><br>
Last Name: <input type="text" ng-model="lastName"><br>
<br>
Full Name: {{firstName + " " + lastName}}

</div>

<script src="personController.js"></script>

// For the next example we will create a new controller file:
angular.module('myApp', []).controller('namesCtrl', function($scope) {
    $scope.names = [
        {name:'Jani',country:'Norway'},
        {name:'Hege',country:'Sweden'},
        {name:'Kai',country:'Denmark'}
    ];
});

//Save the file as  namesController.js:
//And then use the controller file in an application:

<div ng-app="myApp" ng-controller="namesCtrl">

<ul>
  <li ng-repeat="x in names">
    {{ x.name + ', ' + x.country }}
  </li>
</ul>

</div>

<script src="namesController.js"></script>

///////////////////////////////////
// AngularJS Filers

// Filters can be added to expressions and directives using a pipe character.
// AngularJS filters can be used to transform data:

- **currency**:  Format a number to a currency format.
- **filter**:  Select a subset of items from an array.
- **lowercase**: Format a string to lower case.
- **orderBy**: Orders an array by an expression.
- **uppercase**: Format a string to upper case.

//A filter can be added to an expression with a pipe character (|) and a filter.
//(For the next two examples we will use the person controller from the previous chapter)
//The uppercase filter format strings to upper case:
<div ng-app="myApp" ng-controller="personCtrl">

<p>The name is {{ lastName | uppercase }}</p>

</div>

//The lowercase filter format strings to lower case:
<div ng-app="myApp" ng-controller="personCtrl">

<p>The name is {{ lastName | lowercase }}</p>

</div>

//The currency filter formats a number as currency:
<div ng-app="myApp" ng-controller="costCtrl">

<input type="number" ng-model="quantity">
<input type="number" ng-model="price">

<p>Total = {{ (quantity * price) | currency }}</p>

</div> 

//A filter can be added to a directive with a pipe character (|) and a filter.
//The orderBy filter orders an array by an expression:
<div ng-app="myApp" ng-controller="namesCtrl">

<ul>
  <li ng-repeat="x in names | orderBy:'country'">
    {{ x.name + ', ' + x.country }}
  </li>
</ul>

<div>

//An input filter can be added to a directive with a pipe character (|) 
//and filter followed by a colon and a model name.
//The filter filter selects a subset of an array:

<div ng-app="myApp" ng-controller="namesCtrl">

<p><input type="text" ng-model="test"></p>

<ul>
  <li ng-repeat="x in names | filter:test | orderBy:'country'">
    {{ (x.name | uppercase) + ', ' + x.country }}
  </li>
</ul>

</div>

///////////////////////////////////
// AngularJS AJAX - $http

//$http is an AngularJS service for reading data from remote servers.

// The following data can be provided by a web server:
// http://www.w3schools.com/angular/customers.php
// **Check the URL to see the data format**

// AngularJS $http is a core service for reading data from web servers.
// $http.get(url) is the function to use for reading server data.
<div ng-app="myApp" ng-controller="customersCtrl"> 

<ul>
  <li ng-repeat="x in names">
    {{ x.Name + ', ' + x.Country }}
  </li>
</ul>

</div>

<script>
var app = angular.module('myApp', []);
app.controller('customersCtrl', function($scope, $http) {
    $http.get("http://www.w3schools.com/angular/customers.php")
    .success(function(response) {$scope.names = response.records;});
});
</script>

Application explained:

// The AngularJS application is defined by ng-app. The application runs inside a <div>.
// The ng-controller directive names the controller object.
// The customersCtrl function is a standard JavaScript object constructor.
// AngularJS will invoke customersCtrl with a $scope and $http object.
// $scope is the application object (the owner of application variables and functions).
// $http is an XMLHttpRequest object for requesting external data.
// $http.get() reads JSON data from http://www.w3schools.com/angular/customers.php.
// If success, the controller creates a property (names) in the scope, with JSON data from the server.


// Requests for data from a different server (than the requesting page), are called cross-site HTTP requests.
// Cross-site requests are common on the web. Many pages load CSS, images, and scripts from different servers.
// In modern browsers, cross-site HTTP requests from scripts are restricted to same site for security reasons.
// The following line, in our PHP examples, has been added to allow cross-site access.
header("Access-Control-Allow-Origin: *");


///////////////////////////////////
// AngularJS Tables

// Displaying tables with angular is very simple:
<div ng-app="myApp" ng-controller="customersCtrl"> 

<table>
  <tr ng-repeat="x in names">
    <td>{{ x.Name }}</td>
    <td>{{ x.Country }}</td>
  </tr>
</table>

</div>

<script>
var app = angular.module('myApp', []);
app.controller('customersCtrl', function($scope, $http) {
    $http.get("http://www.w3schools.com/angular/customers.php")
    .success(function (response) {$scope.names = response.records;});
});
</script>

// To sort the table, add an orderBy filter: 
<table>
  <tr ng-repeat="x in names | orderBy : 'Country'">
    <td>{{ x.Name }}</td>
    <td>{{ x.Country }}</td>
  </tr>
</table>

// To display the table index, add a <td> with $index: 
<table>
  <tr ng-repeat="x in names">
    <td>{{ $index + 1 }}</td>
    <td>{{ x.Name }}</td>
    <td>{{ x.Country }}</td>
  </tr>
</table>

// Using $even and $odd
<table>
  <tr ng-repeat="x in names">
    <td ng-if="$odd" style="background-color:#f1f1f1">{{ x.Name }}</td>
    <td ng-if="$even">{{ x.Name }}</td>
    <td ng-if="$odd" style="background-color:#f1f1f1">{{ x.Country }}</td>
    <td ng-if="$even">{{ x.Country }}</td>
  </tr>
</table>

///////////////////////////////////
// AngularJS HTML DOM

//AngularJS has directives for binding application data to the attributes of HTML DOM elements.

// The ng-disabled directive binds AngularJS application data to the disabled attribute of HTML elements.

<div ng-app="" ng-init="mySwitch=true">

<p>
<button ng-disabled="mySwitch">Click Me!</button>
</p>

<p>
<input type="checkbox" ng-model="mySwitch">Button
</p>

</div>

//Application explained:

// The ng-disabled directive binds the application data mySwitch to the HTML button's disabled attribute.
// The ng-model directive binds the value of the HTML checkbox element to the value of mySwitch.
// If the value of mySwitch evaluates to true, the button will be disabled: 
<p>
<button disabled>Click Me!</button>
</p>

// If the value of mySwitch evaluates to false, the button will not be disabled: 
<p>
  <button>Click Me!</button>
</p>

// The ng-show directive shows or hides an HTML element.

<div ng-app="">

<p ng-show="true">I am visible.</p>

<p ng-show="false">I am not visible.</p>

</div>

// The ng-show directive shows (or hides) an HTML element based on the value of ng-show.
// You can use any expression that evaluates to true or false:
<div ng-app="">
<p ng-show="hour > 12">I am visible.</p>
</div>

///////////////////////////////////
// AngularJS Events

// AngularJS has its own HTML events directives.

// The ng-click directive defines an AngularJS click event.
<div ng-app="myApp" ng-controller="myCtrl">

<button ng-click="count = count + 1">Click me!</button>

<p>{{ count }}</p>

</div>
<script>
var app = angular.module('myApp', []);
app.controller('myCtrl', function($scope) {
    $scope.count = 0;
});
</script>

// The ng-hide directive can be used to set the visibility of a part of an application.
// The value ng-hide="true" makes an HTML element invisible.
// The value ng-hide="false" makes the element visible.
<div ng-app="myApp" ng-controller="personCtrl">

<button ng-click="toggle()">Toggle</button>

<p ng-hide="myVar">
First Name: <input type="text" ng-model="firstName"><br>
Last Name: <input type="text" ng-model="lastName"><br>
<br>
Full Name: {{firstName + " " + lastName}}
</p>

</div>

<script>
var app = angular.module('myApp', []);
app.controller('personCtrl', function($scope) {
    $scope.firstName = "John",
    $scope.lastName = "Doe"
    $scope.myVar = false;
    $scope.toggle = function() {
        $scope.myVar = !$scope.myVar;
    };
});
</script>

//Application explained:

// The first part of the personController is the same as in the chapter about controllers.
// The application has a default property (a variable): $scope.myVar = false;
// The ng-hide directive sets the visibility, of a <p> element with two input fields, 
// according to the value (true or false) of myVar.
// The function toggle() toggles myVar between true and false.
// The value ng-hide="true" makes the element invisible.


// The ng-show directive can also be used to set the visibility of a part of an application.
// The value ng-show="false" makes an HTML element invisible.
// The value ng-show="true" makes the element visible.
// Here is the same example as above, using ng-show instead of ng-hide:
<div ng-app="myApp" ng-controller="personCtrl">

<button ng-click="toggle()">Toggle</button>

<p ng-show="myVar">
First Name: <input type="text" ng-model="firstName"><br>
Last Name: <input type="text" ng-model="lastName"><br>
<br>
Full Name: {{firstName + " " + lastName}}
</p>

</div>

<script>
var app = angular.module('myApp', []);
app.controller('personCtrl', function($scope) {
    $scope.firstName = "John",
    $scope.lastName = "Doe"
    $scope.myVar = true;
    $scope.toggle = function() {
        $scope.myVar = !$scope.myVar;
    }
});
</script>

///////////////////////////////////
// AngularJS Modules

// An AngularJS module defines an application.
// The module is a container for the different parts of an application.
// The module is a container for the application controllers.
// Controllers always belong to a module.

// This application ("myApp") has one controller ("myCtrl"):

<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
<body>

<div ng-app="myApp" ng-controller="myCtrl">
{{ firstName + " " + lastName }}
</div>

<script>
var app = angular.module("myApp", []);
app.controller("myCtrl", function($scope) {
    $scope.firstName = "John";
    $scope.lastName = "Doe";
});
</script>

</body>
</html>

// It is common in AngularJS applications to put the module and the controllers in JavaScript files.
// In this example, "myApp.js" contains an application module definition, while "myCtrl.js" contains the controller:

<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
<body>

<div ng-app="myApp" ng-controller="myCtrl">
{{ firstName + " " + lastName }}
</div>

<script src="myApp.js"></script>
<script src="myCtrl.js"></script>

</body>
</html>

//myApp.js
var app = angular.module("myApp", []); 

// The [] parameter in the module definition can be used to define dependent modules.

// myCtrl.js
app.controller("myCtrl", function($scope) {
    $scope.firstName  = "John";
    $scope.lastName= "Doe";
});

// Global functions should be avoided in JavaScript. They can easily be overwritten 
// or destroyed by other scripts.

// AngularJS modules reduces this problem, by keeping all functions local to the module.

// While it is common in HTML applications to place scripts at the end of the 
// <body> element, it is recommended that you load the AngularJS library either
// in the <head> or at the start of the <body>.

// This is because calls to angular.module can only be compiled after the library has been loaded.

<!DOCTYPE html>
<html>
<body>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>

<div ng-app="myApp" ng-controller="myCtrl">
{{ firstName + " " + lastName }}
</div>

<script>
var app = angular.module("myApp", []);
app.controller("myCtrl", function($scope) {
    $scope.firstName = "John";
    $scope.lastName = "Doe";
});
</script>

</body>
</html>


///////////////////////////////////
// AngularJS Applications

// AngularJS modules define AngularJS applications.
// AngularJS controllers control AngularJS applications.
// The ng-app directive defines the application, the ng-controller directive defines the controller.
<div ng-app="myApp" ng-controller="myCtrl">
  First Name: <input type="text" ng-model="firstName"><br>
  Last Name: <input type="text" ng-model="lastName"><br>
  <br>
  Full Name: {{firstName + " " + lastName}}
</div>
<script>
  var app = angular.module('myApp', []);
  app.controller('myCtrl', function($scope) {
      $scope.firstName= "John";
      $scope.lastName= "Doe";
  });
</script>

// AngularJS modules define applications:
var app = angular.module('myApp', []);

// AngularJS controllers control applications:
app.controller('myCtrl', function($scope) {
    $scope.firstName= "John";
    $scope.lastName= "Doe";
});
```

## Source & References

**Examples**

- http://www.w3schools.com/angular/angular_examples.asp

**References**

- http://www.w3schools.com/angular/angular_ref_directives.asp
- http://www.w3schools.com/angular/default.asp
- https://teamtreehouse.com/library/angular-basics/

Feedback is welcome! You can find me in:
[@WalterC_87](https://twitter.com/WalterC_87), or
[me@waltercordero.com](mailto:me@waltercordero.com).