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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
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	34	Then save the file in your application/views/ folder.
				35
				36	Loading a View
				37	==============
				38
				39	To load a particular view file you will use the following function::
				40
				41	$this->load->view('name');
				42
				43	Where name is the name of your view file. Note: The .php file extension
				44	does not need to be specified unless you use something other than .php.
				45
				46	Now, open the controller file you made earlier called blog.php, and
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	47	replace the echo statement with the view loading function::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	48
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	49	<?php
				50	class Blog extends CI_Controller {
				51
				52	function index()
				53	{
				54	$this->load->view('blogview');
				55	}
				56	}
				57	?>
				58
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	59	If you visit your site using the URL you did earlier you should see your
				60	new view. The URL was similar to this::
				61
				62	example.com/index.php/blog/
				63
				64	Loading multiple views
				65	======================
				66
				67	CodeIgniter will intelligently handle multiple calls to
				68	$this->load->view from within a controller. If more than one call
				69	happens they will be appended together. For example, you may wish to
				70	have a header view, a menu view, a content view, and a footer view. That
				71	might look something like this::
				72
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	73	<?php
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	74
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	75	class Page extends CI_Controller {
				76
				77	function index()
				78	{
				79	$data['page_title'] = 'Your title';
				80	$this->load->view('header');
				81	$this->load->view('menu');
				82	$this->load->view('content', $data);
				83	$this->load->view('footer');
				84	}
				85
				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
				92	Storing Views within Sub-folders
				93	================================
				94
				95	Your view files can also be stored within sub-folders if you prefer that
				96	type of organization. When doing so you will need to include the folder
				97	name loading the view. Example::
				98
				99	$this->load->view('folder_name/file_name');
				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
				105	an object in the second parameter of the view loading function. Here
				106	is an example using an array::
				107
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	108	$data = array(
				109	'title' => 'My Title',
				110	'heading' => 'My Heading',
				111	'message' => 'My Message'
				112	);
				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
				121	Note: If you use an object, the class variables will be turned into
				122	array elements.
				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
				129	function index()
				130	{
				131	$data['title'] = "My Real Title";
				132	$data['heading'] = "My Real Heading";
				133
				134	$this->load->view('blogview', $data);
				135	}
				136	}
				137	?>
				138
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	139	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]	140	to the array keys in your data::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	141
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	142	<html>
				143	<head>
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	144	<title><?php echo $title;?></title>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	145	</head>
				146	<body>
				147	<h1><?php echo $heading;?></h1>
				148	</body>
				149	</html>
				150
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	151	Then load the page at the URL you've been using and you should see the
				152	variables replaced.
				153
				154	Creating Loops
				155	==============
				156
				157	The data array you pass to your view files is not limited to simple
				158	variables. You can pass multi dimensional arrays, which can be looped to
				159	generate multiple rows. For example, if you pull data from your database
				160	it will typically be in the form of a multi-dimensional array.
				161
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	162	Here's a simple example. Add this to your controller::
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	163
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	164	<?php
				165	class Blog extends CI_Controller {
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	166
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	167	function index()
				168	{
				169	$data['todo_list'] = array('Clean House', 'Call Mom', 'Run Errands');
				170
				171	$data['title'] = "My Real Title";
				172	$data['heading'] = "My Real Heading";
				173
				174	$this->load->view('blogview', $data);
				175	}
				176	}
				177	?>
				178
				179	Now open your view file and create a loop::
				180
				181	<html>
				182	<head>
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	183	<title><?php echo $title;?></title>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	184	</head>
				185	<body>
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	186	<h1><?php echo $heading;?></h1>
				187
				188	<h3>My Todo List</h3>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	189
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	190	<ul>
				191	<?php foreach ($todo_list as $item):?>
				192
				193	<li><?php echo $item;?></li>
				194
				195	<?php endforeach;?>
				196	</ul>
Derek Jones	9607e73	2011-10-05 16:42:42 -0500	[diff] [blame]	197
				198	</body>
				199	</html>
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	200
				201	.. note:: You'll notice that in the example above we are using PHP's
				202	alternative syntax. If you are not familiar with it you can read about
purwandi	5ebf9d1	2011-10-07 16:09:13 +0700	[diff] [blame]	203	it :doc:`here </general/alternative_php>`.
Derek Jones	8ede1a2	2011-10-05 13:34:52 -0500	[diff] [blame]	204
				205	Returning views as data
				206	=======================
				207
				208	There is a third optional parameter lets you change the behavior of
				209	the function so that it returns data as a string rather than sending it
				210	to your browser. This can be useful if you want to process the data in
				211	some way. If you set the parameter to true (boolean) it will return
				212	data. The default behavior is false, which sends it to your browser.
				213	Remember to assign it to a variable if you want the data returned::
				214
				215	$string = $this->load->view('myfile', '', true);
				216