View.php，继承了component，用于渲染视图文件：
1 namespace yii\base;
2
3 use Yii;
4 use yii\helpers\FileHelper;
5 use yii\widgets\Block;
6 use yii\widgets\ContentDecorator;
7 use yii\widgets\FragmentCache;
8
9 /**
10 * View represents a view object in the MVC pattern.
11 *
12 * View provides a set of methods (e.g. [[render()]]) for rendering purpose.
13 * 视图提供了一套渲染页面的方法（例如[render()]）
14 *
15 * @property string|boolean $viewFile The view file currently being rendered. False if no view file is being
16 * rendered. This property is read-only.
17 *
18 * @author Qiang Xue <[email protected]>
19 * @since 2.0
20 */
21 class View extends Component
22 {
23 /**
24 * @event Event an event that is triggered by [[beginPage()]].
25 * beginPage事件名常量，被[beginPage()]触发
26 */
27 const EVENT_BEGIN_PAGE = ‘beginPage‘;
28 /**
29 * @event Event an event that is triggered by [[endPage()]].
30 * endPage事件名常量，被[endPage()]触发
31 */
32 const EVENT_END_PAGE = ‘endPage‘;
33 /**
34 * @event ViewEvent an event that is triggered by [[renderFile()]] right before it renders a view file.
35 * beforeRender事件名常量，被[renderFile()]触发
36 */
37 const EVENT_BEFORE_RENDER = ‘beforeRender‘;
38 /**
39 * @event ViewEvent an event that is triggered by [[renderFile()]] right after it renders a view file.
40 * afterRender事件名常量，被[renderFile()]触发
41 */
42 const EVENT_AFTER_RENDER = ‘afterRender‘;
43
44 /**
45 * @var ViewContextInterface the context under which the [[renderFile()]] method is being invoked.
46 */
47 public $context;
48 /**
49 * @var mixed custom parameters that are shared among view templates.
50 * 在视图模板中共享的自定义参数
51 */
52 public $params = [];
53 /**
54 * @var array a list of available renderers indexed by their corresponding supported file extensions.
55 * Each renderer may be a view renderer object or the configuration for creating the renderer object.
56 * 一个可用的渲染索引列表。每个渲染器是一个渲染器对象或创建渲染对象配置数组
57 * For example, the following configuration enables both Smarty and Twig view renderers:
58 * 下面的配置数组同时支持 Smarty 和 Twig
59 *
60 * ```php
61 * [
62 * ‘tpl‘ => [‘class‘ => ‘yii\smarty\ViewRenderer‘],
63 * ‘twig‘ => [‘class‘ => ‘yii\twig\ViewRenderer‘],
64 * ]
65 * ```
66 *
67 * If no renderer is available for the given view file, the view file will be treated as a normal PHP
68 * and rendered via [[renderPhpFile()]].
69 * 如果没有值，则
70 */
71 public $renderers;
72 /**
73 * @var string the default view file extension. This will be appended to view file names if they don‘t have file extensions.
74 * 默认视图文件扩展名，在视图文件没有扩展名的情况下自动添加
75 */
76 public $defaultExtension = ‘php‘;
77 /**
78 * @var Theme|array|string the theme object or the configuration for creating the theme object.
79 * If not set, it means theming is not enabled.
80 * 主题对象或创建主题对象的配置
81 */
82 public $theme;
83 /**
84 * @var array a list of named output blocks. The keys are the block names and the values
85 * are the corresponding block content. You can call [[beginBlock()]] and [[endBlock()]]
86 * to capture small fragments of a view. They can be later accessed somewhere else
87 * through this property.
88 * 一个输出块列表。键是块名称值为相应的块内容。你可以调用 [ beginblock() ]和[ endblock() ]捕获视图的small fragments
89 * 它们可以在其他地方通过这个属性访问。
90 */
91 public $blocks;
92 /**
93 * @var array a list of currently active fragment cache widgets. This property
94 * is used internally to implement the content caching feature. Do not modify it directly.
95 * 当前active fragment缓存小部件的列表。此属性用于内部实现内容缓存功能。不要直接修改它。
96 * @internal
97 */
98 public $cacheStack = [];
99 /**
100 * @var array a list of placeholders for embedding dynamic contents. This property
101 * is used internally to implement the content caching feature. Do not modify it directly.
102 * 一种嵌入动态内容占位符列表。此属性用于内部实现内容缓存功能。不要直接修改它。
103 * @internal
104 */
105 public $dynamicPlaceholders = [];
106
107 /**
108 * @var array the view files currently being rendered. There may be multiple view files being
109 * rendered at a moment because one view may be rendered within another.
110 * 目前正在渲染的视图文件。可能有多个视图文件被渲染，因为一个视图可以在另一个视图中呈现
111 */
112 private $_viewFiles = [];
113
114
115 /**
116 * Initializes the view component.
117 * 初始化视图组件
118 */
119 public function init()
120 {
121 parent::init();//调用父类的init方法
122 if (is_array($this->theme)) {//如果theme是数组
123 if (!isset($this->theme[‘class‘])) {//且没有设置类名
124 $this->theme[‘class‘] = ‘yii\base\Theme‘;//则类名为‘yii\base\Theme‘
125 }
126 //以配置的形式创建对象
127 $this->theme = Yii::createObject($this->theme);
128 } elseif (is_string($this->theme)) {//否则以字符串参数的形式创建
129 $this->theme = Yii::createObject($this->theme);
130 }
131 }
132
133 /**
134 * Renders a view.
135 * 渲染一个视图
136 * The view to be rendered can be specified in one of the following formats:
137 * 被渲染的视图可以用下列方式指定
138 *
139 * - path alias (e.g. "@app/views/site/index");
140 * 路径别名
141 * - absolute path within application (e.g. "//site/index"): the view name starts with double slashes.
142 * The actual view file will be looked for under the [[Application::viewPath|view path]] of the application.
143 * 绝对路径，将会在[Application::viewPath|view path]下查找文件
144 * - absolute path within current module (e.g. "/site/index"): the view name starts with a single slash.
145 * The actual view file will be looked for under the [[Module::viewPath|view path]] of the [[Controller::module|current module]].
146 * 模块下的绝对路径，将会在[Module::viewPath|view path]下查找文件
147 * - relative view (e.g. "index"): the view name does not start with `@` or `/`. The corresponding view file will be
148 * looked for under the [[ViewContextInterface::getViewPath()|view path]] of the view `$context`.
149 * 相对路径，将会在[ViewContextInterface::getViewPath()|view path]下查找文件
150 * If `$context` is not given, it will be looked for under the directory containing the view currently
151 * being rendered (i.e., this happens when rendering a view within another view).
152 *
153 * @param string $view the view name.
154 * @param array $params the parameters (name-value pairs) that will be extracted and made available in the view file.
155 * @param object $context the context to be assigned to the view and can later be accessed via [[context]]
156 * in the view. If the context implements [[ViewContextInterface]], it may also be used to locate
157 * the view file corresponding to a relative view name.
158 * @return string the rendering result
159 * @throws InvalidParamException if the view cannot be resolved or the view file does not exist.
160 * @see renderFile()
161 */
162 public function render($view, $params = [], $context = null)
163 {
164 //查找视图文件路径
165 $viewFile = $this->findViewFile($view, $context);
166 //调用renderFile()渲染视图文件
167 return $this->renderFile($viewFile, $params, $context);
168 }
时间： 2024-10-27 13:00:46