summaryrefslogtreecommitdiff
path: root/framework/Web/UI/WebControls/THead.php
blob: 32eb2cfa95e49777d552abe7fd3d6a2bc79e0fff (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
<?php
/**
 * THead class file
 *
 * @author Marcus Nyeholt <tanus@users.sourceforge.net> and Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2014 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @package System.Web.UI
 */

/**
 * THead class
 *
 * THead displays a head element on a page. It displays the content
 * enclosed in its body and the page title set by the
 * {@link setTitle Title} property. In addition, stylesheets and JavaScripts registered via
 * {@link TClientScriptManager::registerStyleSheet}, {@link TClientScriptManager::registerStyleSheetFile}
 * {@link TClientScriptManager::registerHeadJavaScript}, and
 * {@link TClientScriptManager::registerHeadJavaScriptFile} will also be displayed
 * in the head.
 * THead also manages and displays meta tags through its {@link getMetaTags MetaTags}
 * property. You can add a meta object to the collection in code dynamically,
 * or add it in template using the following syntax,
 * <code>
 * <com:THead>
 *   <com:TMetaTag HttpEquiv="Pragma" Content="no-cache" />
 *   <com:TMetaTag Name="keywords" Content="Prado" />
 * </com:THead>
 * </code>
 *
 * Note, {@link TPage} has a property {@link TPage::getHead Head} that refers to
 * the THead control currently on the page. A page can have at most one THead
 * control. Although not required, it is recommended to place a THead on your page.
 * Without a THead on the page, stylesheets and javascripts in the current page
 * theme will not be rendered.
 *
 * @author Marcus Nyeholt <tanus@users.sourceforge.net> and Qiang Xue <qiang.xue@gmail.com>
 * @package System.Web.UI
 * @since 3.0
 */
class THead extends TControl
{
	/**
	 * @var TList list of meta name tags to be loaded by {@link THead}
	 */
	private $_metaTags=null;

	/**
	 * Registers the head control with the current page.
	 * This method is invoked when the control enters 'Init' stage.
	 * The method raises 'Init' event.
	 * If you override this method, be sure to call the parent implementation
	 * so that the event handlers can be invoked.
	 * @param TEventParameter event parameter to be passed to the event handlers
	 */
	public function onInit($param)
	{
		parent::onInit($param);
		$this->getPage()->setHead($this);
	}

	/**
	 * Processes an object that is created during parsing template.
	 * This method adds TMetaTag components into the {@link getMetaTags MetaTags}
	 * collection of the head control.
	 * @param string|TComponent text string or component parsed and instantiated in template
	 * @see createdOnTemplate
	 */
	public function addParsedObject($object)
	{
		if($object instanceof TMetaTag)
			$this->getMetaTags()->add($object);
		else
			parent::addParsedObject($object);
	}

	/**
	 * @return string the page title.
	 */
	public function getTitle()
	{
		return $this->getViewState('Title','');
	}

	/**
	 * Sets the page title.
	 * This title will be rendered only if the {@link TPage::getTitle Title} property
	 * of the page is empty.
	 * @param string the page title.
	 */
	public function setTitle($value)
	{
		$this->setViewState('Title',$value,'');
	}

	/**
	 * @return string base URL of the page. This URL is rendered as the 'href' attribute of <base> tag. Defaults to ''.
	 */
	public function getBaseUrl()
	{
		return $this->getViewState('BaseUrl','');
	}

	/**
	 * @param string base URL of the page. This URL is rendered as the 'href' attribute of <base> tag.
	 */
	public function setBaseUrl($url)
	{
		$this->setViewState('BaseUrl',$url,'');
	}

	/**
	 * @return string the URL for the shortcut icon of the page. Defaults to ''.
	 */
	public function getShortcutIcon()
	{
		return $this->getViewState('ShortcutIcon','');
	}

	/**
	 * @param string the URL for the shortcut icon of the page.
	 */
	public function setShortcutIcon($url)
	{
		$this->setViewState('ShortcutIcon',$url,'');
	}

	/**
	 * @return TMetaTagCollection meta tag collection
	 */
	public function getMetaTags()
	{
		if(($metaTags=$this->getViewState('MetaTags',null))===null)
		{
			$metaTags=new TMetaTagCollection;
			$this->setViewState('MetaTags',$metaTags,null);
		}
		return $metaTags;
	}

	/**
	 * Renders the head control.
	 * @param THtmlWriter the writer for rendering purpose.
	 */
	public function render($writer)
	{
		$page=$this->getPage();
		$title=$this->getTitle();
		$writer->write("<head>\n<title>".THttpUtility::htmlEncode($title)."</title>\n");
		if(($baseUrl=$this->getBaseUrl())!=='')
			$writer->write('<base href="'.$baseUrl."\" />\n");
		if(($icon=$this->getShortcutIcon())!=='')
			$writer->write('<link rel="shortcut icon" href="'.$icon."\" />\n");

		if(($metaTags=$this->getMetaTags())!==null)
		{
			foreach($metaTags as $metaTag)
			{
				$metaTag->render($writer);
				$writer->writeLine();
			}
		}
		$cs=$page->getClientScript();
		$cs->renderStyleSheetFiles($writer);
		$cs->renderStyleSheets($writer);
		if($page->getClientSupportsJavaScript())
		{
			$cs->renderHeadScriptFiles($writer);
			$cs->renderHeadScripts($writer);
		}
		parent::render($writer);
		$writer->write("</head>\n");
	}
}