yii2源码学习笔记(十五）

这几天有点忙今天好些了，继续上次的module来吧

     /**
      * Returns the directory that contains the controller classes according to [[controllerNamespace]].
      *根据控制器的命名空间返回控制器的目录路径
      * Note that in order for this method to return a value, you must define
      * an alias for the root namespace of [[controllerNamespace]].
      * 为了使该方法返回正确的值，必须为[[controllerNamespace]]定义一个根别名
      * @return string the directory that contains the controller classes.
      * @throws InvalidParamException if there is no alias defined for the root namespace of [[controllerNamespace]].
      */
     public function getControllerPath()
     {
         //通过将命名空间转换为路径构造别名路径，然后通过getAlias方法取得控制器的绝对路径
         return Yii::getAlias('@' . str_replace('\\', '/', $this->controllerNamespace));
     }

     /**
      * Returns the directory that contains the view files for this module.
      * 取得当前模块的视图文件目录路径
      * @return string the root directory of view files. Defaults to "[[basePath]]/views".
      */
     public function getViewPath()
     {
         if ($this->_viewPath !== null) {
             return $this->_viewPath;
         } else {
             //getBasePath()返回当前模块的根路径，然后拼接出视图文件路径
             return $this->_viewPath = $this->getBasePath() . DIRECTORY_SEPARATOR . 'views';
         }
     }

     /**
      * Sets the directory that contains the view files.设置视图文件目录路径
      * @param string $path the root directory of view files.
      * @throws InvalidParamException if the directory is invalid
      */
     public function setViewPath($path)
     {
         $this->_viewPath = Yii::getAlias($path);
     }

     /**
      * Returns the directory that contains layout view files for this module.
      * 取得当前模块的布局文件路径
      * @return string the root directory of layout files. Defaults to "[[viewPath]]/layouts".
      */
     public function getLayoutPath()
     {
         if ($this->_layoutPath !== null) {
             return $this->_layoutPath;
         } else {//getBasePath()返回当前模块的根路径，然后拼接出布局文件目录路径
             return $this->_layoutPath = $this->getViewPath() . DIRECTORY_SEPARATOR . 'layouts';
         }
     }

     /**
      * Sets the directory that contains the layout files.设置当前模块的布局文件路径
      * @param string $path the root directory or path alias of layout files.
      * @throws InvalidParamException if the directory is invalid
      */
     public function setLayoutPath($path)
     {
         $this->_layoutPath = Yii::getAlias($path);
     }

     /**
      * Defines path aliases. 定义路径别名
      * This method calls [[Yii::setAlias()]] to register the path aliases.
      * This method is provided so that you can define path aliases when configuring a module.
      * 通过调用[[Yii::setAlias()]]注册路径别名，方便在配置模块的时候定义路径别名
      * @property array list of path aliases to be defined. The array keys are alias names
      * (must start with '@') and the array values are the corresponding paths or aliases.
      * See [[setAliases()]] for an example.
      * @param array $aliases list of path aliases to be defined. The array keys are alias names
      * (must start with '@') and the array values are the corresponding paths or aliases.
      * For example,
      *
      * ~~~
      * [
      *     '@models' => '@app/models', // an existing alias
      *     '@backend' => __DIR__ . '/../backend',  // a directory
      * ]
      * ~~~
      */
     public function setAliases($aliases)
     {
         foreach ($aliases as $name => $alias) {
             Yii::setAlias($name, $alias);//调用[[Yii::setAlias()]]路径别名
         }
     }

     /**
      * Checks whether the child module of the specified ID exists.
      * This method supports checking the existence of both child and grand child modules.
      * @param string $id module ID. For grand child modules, use ID path relative to this module (e.g. `admin/content`).
      * @return boolean whether the named module exists. Both loaded and unloaded modules
      * are considered.
      */
     public function hasModule($id)
     {
         if (($pos = strpos($id, '/')) !== false) {
             // sub-module   如果模块ID格式为 `admin/content` 取出当前模块的子模块
             $module = $this->getModule(substr($id, , $pos));
             //如果没有取到，返回false
             return $module === null ? false : $module->hasModule(substr($id, $pos + ));
         } else {
             //模块ID没有父模块的情况，直接判断_modules数组中是否有值
             return isset($this->_modules[$id]);
         }
     }

     /**
      * Retrieves the child module of the specified ID.取出指定模块的子模块
      * This method supports retrieving both child modules and grand child modules.
      * 该方法支持检索子模块和子模块的子模块
      * @param string $id module ID (case-sensitive). To retrieve grand child modules,
      * use ID path relative to this module (e.g. `admin/content`).
      * 检索子模块，使用标识路径相对
      * @param boolean $load whether to load the module if it is not yet loaded. 是否加载模块
      * @return Module|null the module instance, null if the module does not exist. 不存在删除
      * @see hasModule()
      */
     public function getModule($id, $load = true)
     {
         if (($pos = strpos($id, '/')) !== false) {
             // sub-module 判断模块id格式是否为 `admin/content`  取子模块
             $module = $this->getModule(substr($id, , $pos));

             return $module === null ? null : $module->getModule(substr($id, $pos + ), $load);
         }

         if (isset($this->_modules[$id])) {
             if ($this->_modules[$id] instanceof Module) {
                 return $this->_modules[$id];//如果_modules数组中有该模块，直接返回该模块
             } elseif ($load) {//否则，先实例化后返回
                 Yii::trace("Loading module: $id", __METHOD__);
                 /* @var $module Module */
                 $module = Yii::createObject($this->_modules[$id], [$id, $this]);
                 $module->setInstance($module);
                 return $this->_modules[$id] = $module;
             }
         }
         //不存在，返回null
         return null;
     }

     /**
      * Adds a sub-module to this module. 为当前模块添加子模块
      * @param string $id module ID  模块标识
      * @param Module|array|null $module the sub-module to be added to this module. This can
      * be one of the followings:
      *
      * - a [[Module]] object
      * - a configuration array: when [[getModule()]] is called initially, the array
      *   will be used to instantiate the sub-module
      * - null: the named sub-module will be removed from this module
      */
     public function setModule($id, $module)
     {
         if ($module === null) {
             //为空删除
             unset($this->_modules[$id]);
         } else {//存在则添加
             $this->_modules[$id] = $module;
         }
     }