/demo/yii/base/CComponent.php
PHP | 686 lines | 294 code | 30 blank | 362 comment | 82 complexity | d4138ddc750db453268874154ffeacd6 MD5 | raw file
Possible License(s): LGPL-2.1, BSD-2-Clause, Apache-2.0, BSD-3-Clause, GPL-3.0
- <?php
- /**
- * This file contains the foundation classes for component-based and event-driven programming.
- *
- * @author Qiang Xue <qiang.xue@gmail.com>
- * @link http://www.yiiframework.com/
- * @copyright Copyright © 2008-2011 Yii Software LLC
- * @license http://www.yiiframework.com/license/
- */
- /**
- * CComponent is the base class for all components.
- *
- * CComponent implements the protocol of defining, using properties and events.
- *
- * A property is defined by a getter method, and/or a setter method.
- * Properties can be accessed in the way like accessing normal object members.
- * Reading or writing a property will cause the invocation of the corresponding
- * getter or setter method, e.g
- * <pre>
- * $a=$component->text; // equivalent to $a=$component->getText();
- * $component->text='abc'; // equivalent to $component->setText('abc');
- * </pre>
- * The signatures of getter and setter methods are as follows,
- * <pre>
- * // getter, defines a readable property 'text'
- * public function getText() { ... }
- * // setter, defines a writable property 'text' with $value to be set to the property
- * public function setText($value) { ... }
- * </pre>
- *
- * An event is defined by the presence of a method whose name starts with 'on'.
- * The event name is the method name. When an event is raised, functions
- * (called event handlers) attached to the event will be invoked automatically.
- *
- * An event can be raised by calling {@link raiseEvent} method, upon which
- * the attached event handlers will be invoked automatically in the order they
- * are attached to the event. Event handlers must have the following signature,
- * <pre>
- * function eventHandler($event) { ... }
- * </pre>
- * where $event includes parameters associated with the event.
- *
- * To attach an event handler to an event, see {@link attachEventHandler}.
- * You can also use the following syntax:
- * <pre>
- * $component->onClick=$callback; // or $component->onClick->add($callback);
- * </pre>
- * where $callback refers to a valid PHP callback. Below we show some callback examples:
- * <pre>
- * 'handleOnClick' // handleOnClick() is a global function
- * array($object,'handleOnClick') // using $object->handleOnClick()
- * array('Page','handleOnClick') // using Page::handleOnClick()
- * </pre>
- *
- * To raise an event, use {@link raiseEvent}. The on-method defining an event is
- * commonly written like the following:
- * <pre>
- * public function onClick($event)
- * {
- * $this->raiseEvent('onClick',$event);
- * }
- * </pre>
- * where <code>$event</code> is an instance of {@link CEvent} or its child class.
- * One can then raise the event by calling the on-method instead of {@link raiseEvent} directly.
- *
- * Both property names and event names are case-insensitive.
- *
- * CComponent supports behaviors. A behavior is an
- * instance of {@link IBehavior} which is attached to a component. The methods of
- * the behavior can be invoked as if they belong to the component. Multiple behaviors
- * can be attached to the same component.
- *
- * To attach a behavior to a component, call {@link attachBehavior}; and to detach the behavior
- * from the component, call {@link detachBehavior}.
- *
- * A behavior can be temporarily enabled or disabled by calling {@link enableBehavior}
- * or {@link disableBehavior}, respectively. When disabled, the behavior methods cannot
- * be invoked via the component.
- *
- * Starting from version 1.1.0, a behavior's properties (either its public member variables or
- * its properties defined via getters and/or setters) can be accessed through the component it
- * is attached to.
- *
- * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.base
- * @since 1.0
- */
- class CComponent
- {
- private $_e;
- private $_m;
- /**
- * Returns a property value, an event handler list or a behavior based on its name.
- * Do not call this method. This is a PHP magic method that we override
- * to allow using the following syntax to read a property or obtain event handlers:
- * <pre>
- * $value=$component->propertyName;
- * $handlers=$component->eventName;
- * </pre>
- * @param string $name the property name or event name
- * @return mixed the property value, event handlers attached to the event, or the named behavior
- * @throws CException if the property or event is not defined
- * @see __set
- */
- public function __get($name)
- {
- $getter='get'.$name;
- if(method_exists($this,$getter))
- return $this->$getter();
- else if(strncasecmp($name,'on',2)===0 && method_exists($this,$name))
- {
- // duplicating getEventHandlers() here for performance
- $name=strtolower($name);
- if(!isset($this->_e[$name]))
- $this->_e[$name]=new CList;
- return $this->_e[$name];
- }
- else if(isset($this->_m[$name]))
- return $this->_m[$name];
- else if(is_array($this->_m))
- {
- foreach($this->_m as $object)
- {
- if($object->getEnabled() && (property_exists($object,$name) || $object->canGetProperty($name)))
- return $object->$name;
- }
- }
- throw new CException(Yii::t('yii','Property "{class}.{property}" is not defined.',
- array('{class}'=>get_class($this), '{property}'=>$name)));
- }
- /**
- * Sets value of a component property.
- * Do not call this method. This is a PHP magic method that we override
- * to allow using the following syntax to set a property or attach an event handler
- * <pre>
- * $this->propertyName=$value;
- * $this->eventName=$callback;
- * </pre>
- * @param string $name the property name or the event name
- * @param mixed $value the property value or callback
- * @return mixed
- * @throws CException if the property/event is not defined or the property is read only.
- * @see __get
- */
- public function __set($name,$value)
- {
- $setter='set'.$name;
- if(method_exists($this,$setter))
- return $this->$setter($value);
- else if(strncasecmp($name,'on',2)===0 && method_exists($this,$name))
- {
- // duplicating getEventHandlers() here for performance
- $name=strtolower($name);
- if(!isset($this->_e[$name]))
- $this->_e[$name]=new CList;
- return $this->_e[$name]->add($value);
- }
- else if(is_array($this->_m))
- {
- foreach($this->_m as $object)
- {
- if($object->getEnabled() && (property_exists($object,$name) || $object->canSetProperty($name)))
- return $object->$name=$value;
- }
- }
- if(method_exists($this,'get'.$name))
- throw new CException(Yii::t('yii','Property "{class}.{property}" is read only.',
- array('{class}'=>get_class($this), '{property}'=>$name)));
- else
- throw new CException(Yii::t('yii','Property "{class}.{property}" is not defined.',
- array('{class}'=>get_class($this), '{property}'=>$name)));
- }
- /**
- * Checks if a property value is null.
- * Do not call this method. This is a PHP magic method that we override
- * to allow using isset() to detect if a component property is set or not.
- * @param string $name the property name or the event name
- * @return boolean
- */
- public function __isset($name)
- {
- $getter='get'.$name;
- if(method_exists($this,$getter))
- return $this->$getter()!==null;
- else if(strncasecmp($name,'on',2)===0 && method_exists($this,$name))
- {
- $name=strtolower($name);
- return isset($this->_e[$name]) && $this->_e[$name]->getCount();
- }
- else if(is_array($this->_m))
- {
- if(isset($this->_m[$name]))
- return true;
- foreach($this->_m as $object)
- {
- if($object->getEnabled() && (property_exists($object,$name) || $object->canGetProperty($name)))
- return $object->$name!==null;
- }
- }
- return false;
- }
- /**
- * Sets a component property to be null.
- * Do not call this method. This is a PHP magic method that we override
- * to allow using unset() to set a component property to be null.
- * @param string $name the property name or the event name
- * @throws CException if the property is read only.
- * @return mixed
- */
- public function __unset($name)
- {
- $setter='set'.$name;
- if(method_exists($this,$setter))
- $this->$setter(null);
- else if(strncasecmp($name,'on',2)===0 && method_exists($this,$name))
- unset($this->_e[strtolower($name)]);
- else if(is_array($this->_m))
- {
- if(isset($this->_m[$name]))
- $this->detachBehavior($name);
- else
- {
- foreach($this->_m as $object)
- {
- if($object->getEnabled())
- {
- if(property_exists($object,$name))
- return $object->$name=null;
- else if($object->canSetProperty($name))
- return $object->$setter(null);
- }
- }
- }
- }
- else if(method_exists($this,'get'.$name))
- throw new CException(Yii::t('yii','Property "{class}.{property}" is read only.',
- array('{class}'=>get_class($this), '{property}'=>$name)));
- }
- /**
- * Calls the named method which is not a class method.
- * Do not call this method. This is a PHP magic method that we override
- * to implement the behavior feature.
- * @param string $name the method name
- * @param array $parameters method parameters
- * @return mixed the method return value
- */
- public function __call($name,$parameters)
- {
- if($this->_m!==null)
- {
- foreach($this->_m as $object)
- {
- if($object->getEnabled() && method_exists($object,$name))
- return call_user_func_array(array($object,$name),$parameters);
- }
- }
- if(class_exists('Closure', false) && $this->canGetProperty($name) && $this->$name instanceof Closure)
- return call_user_func_array($this->$name, $parameters);
- throw new CException(Yii::t('yii','{class} and its behaviors do not have a method or closure named "{name}".',
- array('{class}'=>get_class($this), '{name}'=>$name)));
- }
- /**
- * Returns the named behavior object.
- * The name 'asa' stands for 'as a'.
- * @param string $behavior the behavior name
- * @return IBehavior the behavior object, or null if the behavior does not exist
- */
- public function asa($behavior)
- {
- return isset($this->_m[$behavior]) ? $this->_m[$behavior] : null;
- }
- /**
- * Attaches a list of behaviors to the component.
- * Each behavior is indexed by its name and should be an instance of
- * {@link IBehavior}, a string specifying the behavior class, or an
- * array of the following structure:
- * <pre>
- * array(
- * 'class'=>'path.to.BehaviorClass',
- * 'property1'=>'value1',
- * 'property2'=>'value2',
- * )
- * </pre>
- * @param array $behaviors list of behaviors to be attached to the component
- */
- public function attachBehaviors($behaviors)
- {
- foreach($behaviors as $name=>$behavior)
- $this->attachBehavior($name,$behavior);
- }
- /**
- * Detaches all behaviors from the component.
- */
- public function detachBehaviors()
- {
- if($this->_m!==null)
- {
- foreach($this->_m as $name=>$behavior)
- $this->detachBehavior($name);
- $this->_m=null;
- }
- }
- /**
- * Attaches a behavior to this component.
- * This method will create the behavior object based on the given
- * configuration. After that, the behavior object will be initialized
- * by calling its {@link IBehavior::attach} method.
- * @param string $name the behavior's name. It should uniquely identify this behavior.
- * @param mixed $behavior the behavior configuration. This is passed as the first
- * parameter to {@link YiiBase::createComponent} to create the behavior object.
- * @return IBehavior the behavior object
- */
- public function attachBehavior($name,$behavior)
- {
- if(!($behavior instanceof IBehavior))
- $behavior=Yii::createComponent($behavior);
- $behavior->setEnabled(true);
- $behavior->attach($this);
- return $this->_m[$name]=$behavior;
- }
- /**
- * Detaches a behavior from the component.
- * The behavior's {@link IBehavior::detach} method will be invoked.
- * @param string $name the behavior's name. It uniquely identifies the behavior.
- * @return IBehavior the detached behavior. Null if the behavior does not exist.
- */
- public function detachBehavior($name)
- {
- if(isset($this->_m[$name]))
- {
- $this->_m[$name]->detach($this);
- $behavior=$this->_m[$name];
- unset($this->_m[$name]);
- return $behavior;
- }
- }
- /**
- * Enables all behaviors attached to this component.
- */
- public function enableBehaviors()
- {
- if($this->_m!==null)
- {
- foreach($this->_m as $behavior)
- $behavior->setEnabled(true);
- }
- }
- /**
- * Disables all behaviors attached to this component.
- */
- public function disableBehaviors()
- {
- if($this->_m!==null)
- {
- foreach($this->_m as $behavior)
- $behavior->setEnabled(false);
- }
- }
- /**
- * Enables an attached behavior.
- * A behavior is only effective when it is enabled.
- * A behavior is enabled when first attached.
- * @param string $name the behavior's name. It uniquely identifies the behavior.
- */
- public function enableBehavior($name)
- {
- if(isset($this->_m[$name]))
- $this->_m[$name]->setEnabled(true);
- }
- /**
- * Disables an attached behavior.
- * A behavior is only effective when it is enabled.
- * @param string $name the behavior's name. It uniquely identifies the behavior.
- */
- public function disableBehavior($name)
- {
- if(isset($this->_m[$name]))
- $this->_m[$name]->setEnabled(false);
- }
- /**
- * Determines whether a property is defined.
- * A property is defined if there is a getter or setter method
- * defined in the class. Note, property names are case-insensitive.
- * @param string $name the property name
- * @return boolean whether the property is defined
- * @see canGetProperty
- * @see canSetProperty
- */
- public function hasProperty($name)
- {
- return method_exists($this,'get'.$name) || method_exists($this,'set'.$name);
- }
- /**
- * Determines whether a property can be read.
- * A property can be read if the class has a getter method
- * for the property name. Note, property name is case-insensitive.
- * @param string $name the property name
- * @return boolean whether the property can be read
- * @see canSetProperty
- */
- public function canGetProperty($name)
- {
- return method_exists($this,'get'.$name);
- }
- /**
- * Determines whether a property can be set.
- * A property can be written if the class has a setter method
- * for the property name. Note, property name is case-insensitive.
- * @param string $name the property name
- * @return boolean whether the property can be written
- * @see canGetProperty
- */
- public function canSetProperty($name)
- {
- return method_exists($this,'set'.$name);
- }
- /**
- * Determines whether an event is defined.
- * An event is defined if the class has a method named like 'onXXX'.
- * Note, event name is case-insensitive.
- * @param string $name the event name
- * @return boolean whether an event is defined
- */
- public function hasEvent($name)
- {
- return !strncasecmp($name,'on',2) && method_exists($this,$name);
- }
- /**
- * Checks whether the named event has attached handlers.
- * @param string $name the event name
- * @return boolean whether an event has been attached one or several handlers
- */
- public function hasEventHandler($name)
- {
- $name=strtolower($name);
- return isset($this->_e[$name]) && $this->_e[$name]->getCount()>0;
- }
- /**
- * Returns the list of attached event handlers for an event.
- * @param string $name the event name
- * @return CList list of attached event handlers for the event
- * @throws CException if the event is not defined
- */
- public function getEventHandlers($name)
- {
- if($this->hasEvent($name))
- {
- $name=strtolower($name);
- if(!isset($this->_e[$name]))
- $this->_e[$name]=new CList;
- return $this->_e[$name];
- }
- else
- throw new CException(Yii::t('yii','Event "{class}.{event}" is not defined.',
- array('{class}'=>get_class($this), '{event}'=>$name)));
- }
- /**
- * Attaches an event handler to an event.
- *
- * An event handler must be a valid PHP callback, i.e., a string referring to
- * a global function name, or an array containing two elements with
- * the first element being an object and the second element a method name
- * of the object.
- *
- * An event handler must be defined with the following signature,
- * <pre>
- * function handlerName($event) {}
- * </pre>
- * where $event includes parameters associated with the event.
- *
- * This is a convenient method of attaching a handler to an event.
- * It is equivalent to the following code:
- * <pre>
- * $component->getEventHandlers($eventName)->add($eventHandler);
- * </pre>
- *
- * Using {@link getEventHandlers}, one can also specify the excution order
- * of multiple handlers attaching to the same event. For example:
- * <pre>
- * $component->getEventHandlers($eventName)->insertAt(0,$eventHandler);
- * </pre>
- * makes the handler to be invoked first.
- *
- * @param string $name the event name
- * @param callback $handler the event handler
- * @throws CException if the event is not defined
- * @see detachEventHandler
- */
- public function attachEventHandler($name,$handler)
- {
- $this->getEventHandlers($name)->add($handler);
- }
- /**
- * Detaches an existing event handler.
- * This method is the opposite of {@link attachEventHandler}.
- * @param string $name event name
- * @param callback $handler the event handler to be removed
- * @return boolean if the detachment process is successful
- * @see attachEventHandler
- */
- public function detachEventHandler($name,$handler)
- {
- if($this->hasEventHandler($name))
- return $this->getEventHandlers($name)->remove($handler)!==false;
- else
- return false;
- }
- /**
- * Raises an event.
- * This method represents the happening of an event. It invokes
- * all attached handlers for the event.
- * @param string $name the event name
- * @param CEvent $event the event parameter
- * @throws CException if the event is undefined or an event handler is invalid.
- */
- public function raiseEvent($name,$event)
- {
- $name=strtolower($name);
- if(isset($this->_e[$name]))
- {
- foreach($this->_e[$name] as $handler)
- {
- if(is_string($handler))
- call_user_func($handler,$event);
- else if(is_callable($handler,true))
- {
- if(is_array($handler))
- {
- // an array: 0 - object, 1 - method name
- list($object,$method)=$handler;
- if(is_string($object)) // static method call
- call_user_func($handler,$event);
- else if(method_exists($object,$method))
- $object->$method($event);
- else
- throw new CException(Yii::t('yii','Event "{class}.{event}" is attached with an invalid handler "{handler}".',
- array('{class}'=>get_class($this), '{event}'=>$name, '{handler}'=>$handler[1])));
- }
- else // PHP 5.3: anonymous function
- call_user_func($handler,$event);
- }
- else
- throw new CException(Yii::t('yii','Event "{class}.{event}" is attached with an invalid handler "{handler}".',
- array('{class}'=>get_class($this), '{event}'=>$name, '{handler}'=>gettype($handler))));
- // stop further handling if param.handled is set true
- if(($event instanceof CEvent) && $event->handled)
- return;
- }
- }
- else if(YII_DEBUG && !$this->hasEvent($name))
- throw new CException(Yii::t('yii','Event "{class}.{event}" is not defined.',
- array('{class}'=>get_class($this), '{event}'=>$name)));
- }
- /**
- * Evaluates a PHP expression or callback under the context of this component.
- *
- * Valid PHP callback can be class method name in the form of
- * array(ClassName/Object, MethodName), or anonymous function (only available in PHP 5.3.0 or above).
- *
- * If a PHP callback is used, the corresponding function/method signature should be
- * <pre>
- * function foo($param1, $param2, ..., $component) { ... }
- * </pre>
- * where the array elements in the second parameter to this method will be passed
- * to the callback as $param1, $param2, ...; and the last parameter will be the component itself.
- *
- * If a PHP expression is used, the second parameter will be "extracted" into PHP variables
- * that can be directly accessed in the expression. See {@link http://us.php.net/manual/en/function.extract.php PHP extract}
- * for more details. In the expression, the component object can be accessed using $this.
- *
- * @param mixed $_expression_ a PHP expression or PHP callback to be evaluated.
- * @param array $_data_ additional parameters to be passed to the above expression/callback.
- * @return mixed the expression result
- * @since 1.1.0
- */
- public function evaluateExpression($_expression_,$_data_=array())
- {
- if(is_string($_expression_) && !function_exists($_expression_))
- {
- extract($_data_);
- return eval('return '.$_expression_.';');
- }
- else
- {
- $_data_[]=$this;
- return call_user_func_array($_expression_, $_data_);
- }
- }
- }
- /**
- * CEvent is the base class for all event classes.
- *
- * It encapsulates the parameters associated with an event.
- * The {@link sender} property describes who raises the event.
- * And the {@link handled} property indicates if the event is handled.
- * If an event handler sets {@link handled} to true, those handlers
- * that are not invoked yet will not be invoked anymore.
- *
- * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.base
- * @since 1.0
- */
- class CEvent extends CComponent
- {
- /**
- * @var object the sender of this event
- */
- public $sender;
- /**
- * @var boolean whether the event is handled. Defaults to false.
- * When a handler sets this true, the rest of the uninvoked event handlers will not be invoked anymore.
- */
- public $handled=false;
- /**
- * @var mixed additional event parameters.
- * @since 1.1.7
- */
- public $params;
- /**
- * Constructor.
- * @param mixed $sender sender of the event
- * @param mixed $params additional parameters for the event
- */
- public function __construct($sender=null,$params=null)
- {
- $this->sender=$sender;
- $this->params=$params;
- }
- }
- /**
- * CEnumerable is the base class for all enumerable types.
- *
- * To define an enumerable type, extend CEnumberable and define string constants.
- * Each constant represents an enumerable value.
- * The constant name must be the same as the constant value.
- * For example,
- * <pre>
- * class TextAlign extends CEnumerable
- * {
- * const Left='Left';
- * const Right='Right';
- * }
- * </pre>
- * Then, one can use the enumerable values such as TextAlign::Left and
- * TextAlign::Right.
- *
- * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.base
- * @since 1.0
- */
- class CEnumerable
- {
- }