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Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	1	#####
				2	Views
				3	#####
				4
				5	A view is simply a web page, or a page fragment, like a header, footer,
				6	sidebar, etc. In fact, views can flexibly be embedded within other views
				7	(within other views, etc., etc.) if you need this type of hierarchy.
				8
				9	Views are never called directly, they must be loaded by a
				10	:doc:`controller <controllers>`. Remember that in an MVC framework, the
				11	Controller acts as the traffic cop, so it is responsible for fetching a
				12	particular view. If you have not read the
				13	:doc:`Controllers <controllers>` page you should do so before
				14	continuing.
				15
				16	Using the example controller you created in the
				17	:doc:`controller <controllers>` page, let's add a view to it.
				18
				19	Creating a View
				20	===============
				21
				22	Using your text editor, create a file called blogview.php, and put this
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	23	in it::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	24
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	25	<html>
				26	<head>
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	27	<title>My Blog</title>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	28	</head>
				29	<body>
				30	<h1>Welcome to my Blog!</h1>
				31	</body>
				32	</html>
				33
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	34	Then save the file in your application/views/ directory.
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	35
				36	Loading a View
				37	==============
				38
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	39	To load a particular view file you will use the following method::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	40
				41	$this->load->view('name');
				42
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	43	Where name is the name of your view file.
				44
				45	.. note:: The .php file extension does not need to be specified
				46	unless you use something other than .php.
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	47
Andrey Andreev	2029231	2013-07-22 14:29:10 +0300	[diff] [blame]	48	Now, open the controller file you made earlier called Blog.php, and
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	49	replace the echo statement with the view loading method::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	50
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	51	<?php
				52	class Blog extends CI_Controller {
				53
Andrey Andreev	d8e1ac7	2012-03-26 22:22:37 +0300	[diff] [blame]	54	public function index()
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	55	{
				56	$this->load->view('blogview');
				57	}
				58	}
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	59
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	60	If you visit your site using the URL you did earlier you should see your
				61	new view. The URL was similar to this::
				62
				63	example.com/index.php/blog/
				64
				65	Loading multiple views
				66	======================
				67
				68	CodeIgniter will intelligently handle multiple calls to
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	69	``$this->load->view()`` from within a controller. If more than one call
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	70	happens they will be appended together. For example, you may wish to
				71	have a header view, a menu view, a content view, and a footer view. That
				72	might look something like this::
				73
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	74	<?php
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	75
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	76	class Page extends CI_Controller {
				77
Andrey Andreev	d8e1ac7	2012-03-26 22:22:37 +0300	[diff] [blame]	78	public function index()
				79	{
				80	$data['page_title'] = 'Your title';
				81	$this->load->view('header');
				82	$this->load->view('menu');
				83	$this->load->view('content', $data);
				84	$this->load->view('footer');
				85	}
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	86
				87	}
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	88
				89	In the example above, we are using "dynamically added data", which you
				90	will see below.
				91
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	92	Storing Views within Sub-directories
				93	====================================
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	94
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	95	Your view files can also be stored within sub-directories if you prefer
				96	that type of organization. When doing so you will need to include the
				97	directory name loading the view. Example::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	98
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	99	$this->load->view('directory_name/file_name');
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	100
				101	Adding Dynamic Data to the View
				102	===============================
				103
				104	Data is passed from the controller to the view by way of an array or
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	105	an object in the second parameter of the view loading method. Here
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	106	is an example using an array::
				107
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	108	$data = array(
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	109	'title' => 'My Title',
				110	'heading' => 'My Heading',
				111	'message' => 'My Message'
				112	);
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	113
				114	$this->load->view('blogview', $data);
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	115
				116	And here's an example using an object::
				117
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	118	$data = new Someclass();
				119	$this->load->view('blogview', $data);
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	120
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	121	.. note:: If you use an object, the class variables will be turned
				122	into array elements.
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	123
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	124	Let's try it with your controller file. Open it add this code::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	125
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	126	<?php
				127	class Blog extends CI_Controller {
				128
Andrey Andreev	d8e1ac7	2012-03-26 22:22:37 +0300	[diff] [blame]	129	public function index()
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	130	{
				131	$data['title'] = "My Real Title";
				132	$data['heading'] = "My Real Heading";
				133
				134	$this->load->view('blogview', $data);
				135	}
				136	}
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	137
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	138	Now open your view file and change the text to variables that correspond
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	139	to the array keys in your data::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	140
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	141	<html>
				142	<head>
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	143	<title><?php echo $title;?></title>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	144	</head>
				145	<body>
				146	<h1><?php echo $heading;?></h1>
				147	</body>
				148	</html>
				149
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	150	Then load the page at the URL you've been using and you should see the
				151	variables replaced.
				152
				153	Creating Loops
				154	==============
				155
				156	The data array you pass to your view files is not limited to simple
				157	variables. You can pass multi dimensional arrays, which can be looped to
				158	generate multiple rows. For example, if you pull data from your database
				159	it will typically be in the form of a multi-dimensional array.
				160
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	161	Here's a simple example. Add this to your controller::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	162
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	163	<?php
				164	class Blog extends CI_Controller {
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	165
Andrey Andreev	d8e1ac7	2012-03-26 22:22:37 +0300	[diff] [blame]	166	public function index()
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	167	{
				168	$data['todo_list'] = array('Clean House', 'Call Mom', 'Run Errands');
				169
				170	$data['title'] = "My Real Title";
				171	$data['heading'] = "My Real Heading";
				172
				173	$this->load->view('blogview', $data);
				174	}
				175	}
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	176
				177	Now open your view file and create a loop::
				178
				179	<html>
				180	<head>
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	181	<title><?php echo $title;?></title>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	182	</head>
				183	<body>
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	184	<h1><?php echo $heading;?></h1>
				185
				186	<h3>My Todo List</h3>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	187
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	188	<ul>
				189	<?php foreach ($todo_list as $item):?>
				190
				191	<li><?php echo $item;?></li>
				192
				193	<?php endforeach;?>
				194	</ul>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	195
				196	</body>
				197	</html>
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	198
				199	.. note:: You'll notice that in the example above we are using PHP's
				200	alternative syntax. If you are not familiar with it you can read about
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	201	it :doc:`here <alternative_php>`.
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	202
				203	Returning views as data
				204	=======================
				205
				206	There is a third optional parameter lets you change the behavior of
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	207	the method so that it returns data as a string rather than sending it
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	208	to your browser. This can be useful if you want to process the data in
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	209	some way. If you set the parameter to TRUE (boolean) it will return
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	210	data. The default behavior is false, which sends it to your browser.
				211	Remember to assign it to a variable if you want the data returned::
				212
Andrey Andreev	16a704c	2012-11-09 17:25:00 +0200	[diff] [blame]	213	$string = $this->load->view('myfile', '', TRUE);