Widget.php 6.71 KB
Newer Older
Qiang Xue committed
1 2 3
<?php
/**
 * @link http://www.yiiframework.com/
Qiang Xue committed
4
 * @copyright Copyright (c) 2008 Yii Software LLC
Qiang Xue committed
5 6 7 8 9
 * @license http://www.yiiframework.com/license/
 */

namespace yii\base;

Qiang Xue committed
10 11
use Yii;

Qiang Xue committed
12 13 14 15 16 17
/**
 * Widget is the base class for widgets.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @since 2.0
 */
Qiang Xue committed
18
class Widget extends Component
Qiang Xue committed
19 20
{
	/**
21 22
	 * @var integer a counter used to generate [[id]] for widgets.
	 * @internal
Qiang Xue committed
23
	 */
24 25 26 27 28 29 30 31
	public static $_counter = 0;
	/**
	 * @var Widget[] the widgets that are currently being rendered (not ended). This property
	 * is maintained by [[begin()]] and [[end()]] methods.
	 * @internal
	 */
	public static $_stack = array();

32
	
33 34 35 36 37 38 39
	/**
	 * Begins a widget.
	 * This method creates an instance of the calling class. It will apply the configuration
	 * to the created instance. A matching [[end()]] call should be called later.
	 * @param array $config name-value pairs that will be used to initialize the object properties
	 * @return Widget the newly created widget instance
	 */
40
	public static function begin($config = array())
41 42 43
	{
		$config['class'] = get_called_class();
		/** @var Widget $widget */
44
		$widget = Yii::createObject($config);
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
		self::$_stack[] = $widget;
		return $widget;
	}

	/**
	 * Ends a widget.
	 * Note that the rendering result of the widget is directly echoed out.
	 * @return Widget the widget instance that is ended.
	 * @throws InvalidCallException if [[begin()]] and [[end()]] calls are not properly nested
	 */
	public static function end()
	{
		if (!empty(self::$_stack)) {
			$widget = array_pop(self::$_stack);
			if (get_class($widget) === get_called_class()) {
				$widget->run();
				return $widget;
			} else {
				throw new InvalidCallException("Expecting end() of " . get_class($widget) . ", found " . get_called_class());
			}
		} else {
			throw new InvalidCallException("Unexpected " . get_called_class() . '::end() call. A matching begin() is not found.');
		}
	}

	/**
	 * Creates a widget instance and runs it.
	 * The widget rendering result is returned by this method.
	 * @param array $config name-value pairs that will be used to initialize the object properties
	 * @return string the rendering result of the widget.
	 */
76
	public static function widget($config = array())
77 78 79 80 81
	{
		ob_start();
		ob_implicit_flush(false);
		/** @var Widget $widget */
		$config['class'] = get_called_class();
82
		$widget = Yii::createObject($config);
83 84 85
		$widget->run();
		return ob_get_clean();
	}
Qiang Xue committed
86

87 88
	private $_id;
	
Qiang Xue committed
89 90 91 92 93 94 95 96
	/**
	 * Returns the ID of the widget.
	 * @param boolean $autoGenerate whether to generate an ID if it is not set previously
	 * @return string ID of the widget.
	 */
	public function getId($autoGenerate = true)
	{
		if ($autoGenerate && $this->_id === null) {
Qiang Xue committed
97
			$this->_id = 'w' . self::$_counter++;
Qiang Xue committed
98 99 100 101 102 103 104 105 106 107 108 109 110
		}
		return $this->_id;
	}

	/**
	 * Sets the ID of the widget.
	 * @param string $value id of the widget.
	 */
	public function setId($value)
	{
		$this->_id = $value;
	}

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
	private $_view;
	
	/**
	 * Returns the view object that can be used to render views or view files.
	 * The [[render()]] and [[renderFile()]] methods will use
	 * this view object to implement the actual view rendering.
	 * If not set, it will default to the "view" application component.
	 * @return View the view object that can be used to render views or view files.
	 */
	public function getView()
	{
		if ($this->_view === null) {
			$this->_view = Yii::$app->getView();
		}
		return $this->_view;
	}

	/**
	 * Sets the view object to be used by this widget.
	 * @param View $view the view object that can be used to render views or view files.
	 */
	public function setView($view)
	{
		$this->_view = $view;
	}

Qiang Xue committed
137 138 139 140 141 142 143 144 145
	/**
	 * Executes the widget.
	 */
	public function run()
	{
	}

	/**
	 * Renders a view.
Qiang Xue committed
146 147 148 149 150 151 152 153 154 155 156 157
	 * The view to be rendered can be specified in one of the following formats:
	 *
	 * - path alias (e.g. "@app/views/site/index");
	 * - absolute path within application (e.g. "//site/index"): the view name starts with double slashes.
	 *   The actual view file will be looked for under the [[Application::viewPath|view path]] of the application.
	 * - absolute path within module (e.g. "/site/index"): the view name starts with a single slash.
	 *   The actual view file will be looked for under the [[Module::viewPath|view path]] of the currently
	 *   active module.
	 * - relative path (e.g. "index"): the actual view file will be looked for under [[viewPath]].
	 *
	 * If the view name does not contain a file extension, it will use the default one `.php`.

Qiang Xue committed
158 159 160 161
	 * @param string $view the view name. Please refer to [[findViewFile()]] on how to specify a view name.
	 * @param array $params the parameters (name-value pairs) that should be made available in the view.
	 * @return string the rendering result.
	 * @throws InvalidParamException if the view file does not exist.
Qiang Xue committed
162 163 164
	 */
	public function render($view, $params = array())
	{
Qiang Xue committed
165
		$viewFile = $this->findViewFile($view);
166
		return $this->getView()->renderFile($viewFile, $params, $this);
Qiang Xue committed
167 168 169
	}

	/**
Qiang Xue committed
170 171 172 173 174
	 * Renders a view file.
	 * @param string $file the view file to be rendered. This can be either a file path or a path alias.
	 * @param array $params the parameters (name-value pairs) that should be made available in the view.
	 * @return string the rendering result.
	 * @throws InvalidParamException if the view file does not exist.
Qiang Xue committed
175
	 */
Qiang Xue committed
176
	public function renderFile($file, $params = array())
Qiang Xue committed
177
	{
178
		return $this->getView()->renderFile($file, $params, $this);
Qiang Xue committed
179
	}
Qiang Xue committed
180 181 182 183 184 185 186 187 188 189 190 191

	/**
	 * Returns the directory containing the view files for this widget.
	 * The default implementation returns the 'views' subdirectory under the directory containing the widget class file.
	 * @return string the directory containing the view files for this widget.
	 */
	public function getViewPath()
	{
		$className = get_class($this);
		$class = new \ReflectionClass($className);
		return dirname($class->getFileName()) . DIRECTORY_SEPARATOR . 'views';
	}
Qiang Xue committed
192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213

	/**
	 * Finds the view file based on the given view name.
	 * @param string $view the view name or the path alias of the view file. Please refer to [[render()]]
	 * on how to specify this parameter.
	 * @return string the view file path. Note that the file may not exist.
	 */
	protected function findViewFile($view)
	{
		if (strncmp($view, '@', 1) === 0) {
			// e.g. "@app/views/main"
			$file = Yii::getAlias($view);
		} elseif (strncmp($view, '//', 2) === 0) {
			// e.g. "//layouts/main"
			$file = Yii::$app->getViewPath() . DIRECTORY_SEPARATOR . ltrim($view, '/');
		} elseif (strncmp($view, '/', 1) === 0 && Yii::$app->controller !== null) {
			// e.g. "/site/index"
			$file = Yii::$app->controller->module->getViewPath() . DIRECTORY_SEPARATOR . ltrim($view, '/');
		} else {
			$file = $this->getViewPath() . DIRECTORY_SEPARATOR . ltrim($view, '/');
		}

Qiang Xue committed
214
		return pathinfo($file, PATHINFO_EXTENSION) === '' ? $file . '.php' : $file;
Qiang Xue committed
215
	}
Zander Baldwin committed
216
}