From ad4cf9e8fa36b65ffaebd30dfdebf530cf3a2d90 Mon Sep 17 00:00:00 2001
From: Qiang Xue <qiang.xue@gmail.com>
Date: Fri, 5 Apr 2013 21:12:49 -0400
Subject: [PATCH] Added beforeRender and afterRender to View.

---
 framework/base/ActionEvent.php |  4 ++-
 framework/base/View.php        | 55 ++++++++++++++++++++++++++++++++++++++----
 framework/base/ViewEvent.php   | 44 +++++++++++++++++++++++++++++++++
 3 files changed, 97 insertions(+), 6 deletions(-)
 create mode 100644 framework/base/ViewEvent.php

diff --git a/framework/base/ActionEvent.php b/framework/base/ActionEvent.php
index 7c5a40c..9507b12 100644
--- a/framework/base/ActionEvent.php
+++ b/framework/base/ActionEvent.php
@@ -22,7 +22,9 @@ class ActionEvent extends Event
 	 */
 	public $action;
 	/**
-	 * @var boolean whether to continue running the action.
+	 * @var boolean whether to continue running the action. Event handlers of
+	 * [[Controller::EVENT_BEFORE_ACTION]] may set this property to decide whether
+	 * to continue running the current action.
 	 */
 	public $isValid = true;
 
diff --git a/framework/base/View.php b/framework/base/View.php
index d3d9339..9f382c6 100644
--- a/framework/base/View.php
+++ b/framework/base/View.php
@@ -22,6 +22,15 @@ use yii\helpers\FileHelper;
 class View extends Component
 {
 	/**
+	 * @event Event an event that is triggered by [[renderFile()]] right before it renders a view file.
+	 */
+	const EVENT_BEFORE_RENDER = 'beforeRender';
+	/**
+	 * @event Event an event that is triggered by [[renderFile()]] right after it renders a view file.
+	 */
+	const EVENT_AFTER_RENDER = 'afterRender';
+
+	/**
 	 * @var object the object that owns this view. This can be a controller, a widget, or any other object.
 	 */
 	public $context;
@@ -47,7 +56,7 @@ class View extends Component
 	public $clips;
 	/**
 	 * @var Widget[] the widgets that are currently being rendered (not ended). This property
-	 * is maintained by [[beginWidget()]] and [[endWidget()]] methods. Do not modify it directly.
+	 * is maintained by [[beginWidget()]] and [[endWidget()]] methods. Do not modify it.
 	 */
 	public $widgetStack = array();
 	/**
@@ -140,10 +149,14 @@ class View extends Component
 			$this->context = $context;
 		}
 
-		if ($this->renderer !== null) {
-			$output = $this->renderer->render($this, $viewFile, $params);
-		} else {
-			$output = $this->renderPhpFile($viewFile, $params);
+		$output = '';
+		if ($this->beforeRender($viewFile)) {
+			if ($this->renderer !== null) {
+				$output = $this->renderer->render($this, $viewFile, $params);
+			} else {
+				$output = $this->renderPhpFile($viewFile, $params);
+			}
+			$this->afterRender($viewFile, $output);
 		}
 
 		$this->context = $oldContext;
@@ -152,6 +165,38 @@ class View extends Component
 	}
 
 	/**
+	 * This method is invoked right before [[renderFile()]] renders a view file.
+	 * The default implementation will trigger the [[EVENT_BEFORE_RENDER]] event.
+	 * If you override this method, make sure you call the parent implementation first.
+	 * @param string $viewFile the view file to be rendered
+	 * @return boolean whether to continue rendering the view file.
+	 */
+	public function beforeRender($viewFile)
+	{
+		$event = new ViewEvent($viewFile);
+		$this->trigger(self::EVENT_BEFORE_RENDER, $event);
+		return $event->isValid;
+	}
+
+	/**
+	 * This method is invoked right after [[renderFile()]] renders a view file.
+	 * The default implementation will trigger the [[EVENT_AFTER_RENDER]] event.
+	 * If you override this method, make sure you call the parent implementation first.
+	 * @param string $viewFile the view file to be rendered
+	 * @param string $output the rendering result of the view file. Updates to this parameter
+	 * will be passed back and returned by [[renderFile()]].
+	 */
+	public function afterRender($viewFile, &$output)
+	{
+		if ($this->hasEventHandlers(self::EVENT_AFTER_RENDER)) {
+			$event = new ViewEvent($viewFile);
+			$event->output = $output;
+			$this->trigger(self::EVENT_AFTER_RENDER, $event);
+			$output = $event->output;
+		}
+	}
+
+	/**
 	 * Renders a view file as a PHP script.
 	 *
 	 * This method treats the view file as a PHP script and includes the file.
diff --git a/framework/base/ViewEvent.php b/framework/base/ViewEvent.php
new file mode 100644
index 0000000..cac7be4
--- /dev/null
+++ b/framework/base/ViewEvent.php
@@ -0,0 +1,44 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\base;
+
+/**
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class ViewEvent extends Event
+{
+	/**
+	 * @var string the rendering result of [[View::renderFile()]].
+	 * Event handlers may modify this property and the modified output will be
+	 * returned by [[View::renderFile()]]. This property is only used
+	 * by [[View::EVENT_AFTER_RENDER]] event.
+	 */
+	public $output;
+	/**
+	 * @var string the view file path that is being rendered by [[View::renderFile()]].
+	 */
+	public $viewFile;
+	/**
+	 * @var boolean whether to continue rendering the view file. Event handlers of
+	 * [[View::EVENT_BEFORE_RENDER]] may set this property to decide whether
+	 * to continue rendering the current view file.
+	 */
+	public $isValid = true;
+
+	/**
+	 * Constructor.
+	 * @param string $viewFile the view file path that is being rendered by [[View::renderFile()]].
+	 * @param array $config name-value pairs that will be used to initialize the object properties
+	 */
+	public function __construct($viewFile, $config = array())
+	{
+		$this->viewFile = $viewFile;
+		parent::__construct($config);
+	}
+}
\ No newline at end of file