Initial Commit

database/php/pear/examples/bubbling.php

@@ -0,0 +1,115 @@
+<?PHP
+/**
+ * example that shows how to create event bubbling
+ *
+ * This allows you to create several levels of event handling and you
+ * may post a notification to any of these levels.
+ *
+ * After a notification has been posted on a lower level, it will bubble
+ * up through all other levels.
+ *
+ * @package    Event_Dispatcher
+ * @subpackage Examples
+ * @author     Stephan Schmidt <schst@php.net>
+ */
+ 
+/**
+ * load Event_Dispatcher package
+ */
+require_once 'Event/Dispatcher.php';
+
+/**
+ * example sender class
+ */
+class sender
+{
+    var $_dispatcher = null;
+    
+    function sender(&$dispatcher)
+    {
+        $this->_dispatcher = &$dispatcher;
+    }
+    
+    function foo($bubble = true)
+    {
+        $this->_dispatcher->post($this, 'onFoo', 'Some Info...', true, $bubble);
+    }
+}
+
+/**
+ * example observer
+ */
+function receiver1(&$notification)
+{
+    echo "receiver 1 received notification<br />\n";
+}
+
+/**
+ * example observer
+ */
+function receiver2(&$notification)
+{
+    echo "receiver 2 received notification<br />\n";
+}
+
+/**
+ * example observer
+ */
+function receiver3(&$notification)
+{
+    echo "receiver 3 received notification<br />\n";
+}
+
+// get the different dispatchers
+$dispatcher1 = &Event_Dispatcher::getInstance();
+$dispatcher2 = &Event_Dispatcher::getInstance('child');
+$dispatcher3 = &Event_Dispatcher::getInstance('grandchild');
+
+// create senders in two different levels
+$sender1 = &new sender($dispatcher1);
+$sender2 = &new sender($dispatcher2);
+
+// build three levels
+$dispatcher1->addNestedDispatcher($dispatcher2);
+$dispatcher2->addNestedDispatcher($dispatcher3);
+
+// add observers in level one and two
+$dispatcher1->addObserver('receiver1', 'onFoo');
+$dispatcher2->addObserver('receiver2', 'onFoo');
+
+// this will bubble up from 1 to 3
+echo 'sender1->foo()<br />';
+$sender1->foo();
+
+// this will not bubble up
+echo '<br />';
+echo 'sender1->foo(), but disable bubbling<br />';
+$sender1->foo(false);
+
+
+// this will bubble up from 2 to 3
+echo '<br />';
+echo 'sender2->foo()<br />';
+$sender2->foo();
+
+// This observer will receive the two pending notifications on level 3
+echo '<br />';
+echo 'dispatcher3->addObserver()<br />';
+$dispatcher3->addObserver('receiver3', 'onFoo');
+
+// remove one level
+$success = $dispatcher1->removeNestedDispatcher($dispatcher2);
+if ($success === true) {
+    echo '<br />';
+	echo 'removed nested dispatcher2 from dispatcher1<br />';
+}
+
+// this will stay in level 1
+echo 'sender1->foo()<br />';
+$sender1->foo();
+
+// this will bubble up from 2-3
+echo '<br />';
+echo 'sender2->foo()<br />';
+$sender2->foo();
+?>