Class yii\base\Widget

All Classes | Properties | Methods | Events
Inheritanceyii\base\Widget » yii\base\Component » yii\base\BaseObject
Implementsyii\base\Configurable, yii\base\ViewContextInterface
Subclassesluya\admin\ngrest\aw\ActiveWindowFormWidget, luya\admin\ngrest\aw\CallbackButtonFileDownloadWidget, luya\admin\ngrest\aw\CallbackButtonWidget, luya\base\Widget, luya\cms\widgets\LangSwitcher, luya\cms\widgets\NavTree, luya\lazyload\LazyLoad, luya\texttospeech\TextToSpeechWidget, luya\web\Svg, luya\widgets\SubmitButtonWidget, yii\captcha\Captcha, yii\console\widgets\Table, yii\grid\GridView, yii\widgets\ActiveForm, yii\widgets\BaseListView, yii\widgets\Block, yii\widgets\Breadcrumbs, yii\widgets\ContentDecorator, yii\widgets\DetailView, yii\widgets\FragmentCache, yii\widgets\InputWidget, yii\widgets\LinkPager, yii\widgets\LinkSorter, yii\widgets\ListView, yii\widgets\MaskedInput, yii\widgets\Menu, yii\widgets\Pjax, yii\widgets\Spaceless
Available since version2.0
Source Code https://github.com/yiisoft/yii2/blob/master/framework/base/Widget.php

Widget is the base class for widgets.

For more details and usage information on Widget, see the guide article on widgets.

Public Properties

Hide inherited properties

Property Type Description Defined By
$autoIdPrefix string The prefix to the automatically generated widget IDs. yii\base\Widget
$behaviors yii\base\Behavior[] List of behaviors attached to this component. yii\base\Component
$id string|null ID of the widget. yii\base\Widget
$view yii\web\View The view object that can be used to render views or view files. yii\base\Widget
$viewPath string The directory containing the view files for this widget. yii\base\Widget

Public Methods

Hide inherited methods

Method Description Defined By
__call() Calls the named method which is not a class method. yii\base\Component
__clone() This method is called after the object is created by cloning an existing one. yii\base\Component
__construct() Constructor. yii\base\BaseObject
__get() Returns the value of a component property. yii\base\Component
__isset() Checks if a property is set, i.e. defined and not null. yii\base\Component
__set() Sets the value of a component property. yii\base\Component
__unset() Sets a component property to be null. yii\base\Component
afterRun() This method is invoked right after a widget is executed. yii\base\Widget
attachBehavior() Attaches a behavior to this component. yii\base\Component
attachBehaviors() Attaches a list of behaviors to the component. yii\base\Component
beforeRun() This method is invoked right before the widget is executed. yii\base\Widget
begin() Begins a widget. yii\base\Widget
behaviors() Returns a list of behaviors that this component should behave as. yii\base\Component
canGetProperty() Returns a value indicating whether a property can be read. yii\base\Component
canSetProperty() Returns a value indicating whether a property can be set. yii\base\Component
className() Returns the fully qualified name of this class. yii\base\BaseObject
detachBehavior() Detaches a behavior from the component. yii\base\Component
detachBehaviors() Detaches all behaviors from the component. yii\base\Component
end() Ends a widget. yii\base\Widget
ensureBehaviors() Makes sure that the behaviors declared in behaviors() are attached to this component. yii\base\Component
getBehavior() Returns the named behavior object. yii\base\Component
getBehaviors() Returns all behaviors attached to this component. yii\base\Component
getId() Returns the ID of the widget. yii\base\Widget
getView() Returns the view object that can be used to render views or view files. yii\base\Widget
getViewPath() Returns the directory containing the view files for this widget. yii\base\Widget
hasEventHandlers() Returns a value indicating whether there is any handler attached to the named event. yii\base\Component
hasMethod() Returns a value indicating whether a method is defined. yii\base\Component
hasProperty() Returns a value indicating whether a property is defined for this component. yii\base\Component
init() Initializes the object. yii\base\Widget
off() Detaches an existing event handler from this component. yii\base\Component
on() Attaches an event handler to an event. yii\base\Component
render() Renders a view. yii\base\Widget
renderFile() Renders a view file. yii\base\Widget
run() Executes the widget. yii\base\Widget
setId() Sets the ID of the widget. yii\base\Widget
setView() Sets the view object to be used by this widget. yii\base\Widget
trigger() Triggers an event. yii\base\Component
widget() Creates a widget instance and runs it. yii\base\Widget

Events

Hide inherited events

Event Type Description Defined By
EVENT_AFTER_RUN yii\base\WidgetEvent An event raised right after executing a widget. (available since version 2.0.11) yii\base\Widget
EVENT_BEFORE_RUN yii\base\WidgetEvent An event raised right before executing a widget. (available since version 2.0.11) yii\base\Widget
EVENT_INIT yii\base\Event An event that is triggered when the widget is initialized via init(). (available since version 2.0.11) yii\base\Widget

Property Details

Hide inherited properties

$autoIdPrefix public static property

The prefix to the automatically generated widget IDs.

See also getId().

public static string $autoIdPrefix = 'w'
$id public property

ID of the widget. Note that the type of this property differs in getter and setter. See getId() and setId() for details.

public string|null $id = null
$view public property

The view object that can be used to render views or view files. Note that the type of this property differs in getter and setter. See getView() and setView() for details.

public yii\web\View $view = null
$viewPath public property

The directory containing the view files for this widget.

public string $viewPath = null

Method Details

Hide inherited methods

__call() public method

Defined in: yii\base\Component::__call()

Calls the named method which is not a class method.

This method will check if any attached behavior has the named method and will execute it if available.

Do not call this method directly as it is a PHP magic method that will be implicitly called when an unknown method is being invoked.

public mixed __call ( $name, $params )
$name string

The method name
$params array

Method parameters
return mixed

The method return value
throws yii\base\UnknownMethodException

when calling unknown method

 

                public function __call($name, $params)
{
    $this->ensureBehaviors();
    foreach ($this->_behaviors as $object) {
        if ($object->hasMethod($name)) {
            return call_user_func_array([$object, $name], $params);
        }
    }
    throw new UnknownMethodException('Calling unknown method: ' . get_class($this) . "::$name()");
}
__clone() public method

Defined in: yii\base\Component::__clone()

This method is called after the object is created by cloning an existing one.

It removes all behaviors because they are attached to the old object.

public void __clone ( )

                public function __clone()
{
    $this->_events = [];
    $this->_eventWildcards = [];
    $this->_behaviors = null;
}
__construct() public method

Defined in: yii\base\BaseObject::__construct()

Constructor.

The default implementation does two things:

  • Initializes the object with the given configuration $config.
  • Call init().

If this method is overridden in a child class, it is recommended that

  • the last parameter of the constructor is a configuration array, like $config here.
  • call the parent implementation at the end of the constructor.
public void __construct ( $config = [] )
$config array

Name-value pairs that will be used to initialize the object properties

 

                public function __construct($config = [])
{
    if (!empty($config)) {
        Yii::configure($this, $config);
    }
    $this->init();
}
__get() public method

Defined in: yii\base\Component::__get()

Returns the value of a component property.

This method will check in the following order and act accordingly:

  • a property defined by a getter: return the getter result
  • a property of a behavior: return the behavior property value

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing $value = $component->property;.

See also __set().

public mixed __get ( $name )
$name string

The property name
return mixed

The property value or the value of a behavior's property
throws yii\base\UnknownPropertyException

if the property is not defined
throws yii\base\InvalidCallException

if the property is write-only.

 

                public function __get($name)
{
    $getter = 'get' . $name;
    if (method_exists($this, $getter)) {
        // read property, e.g. getName()
        return $this->$getter();
    }
    // behavior property
    $this->ensureBehaviors();
    foreach ($this->_behaviors as $behavior) {
        if ($behavior->canGetProperty($name)) {
            return $behavior->$name;
        }
    }
    if (method_exists($this, 'set' . $name)) {
        throw new InvalidCallException('Getting write-only property: ' . get_class($this) . '::' . $name);
    }
    throw new UnknownPropertyException('Getting unknown property: ' . get_class($this) . '::' . $name);
}
__isset() public method

Defined in: yii\base\Component::__isset()

Checks if a property is set, i.e. defined and not null.

This method will check in the following order and act accordingly:

  • a property defined by a setter: return whether the property is set
  • a property of a behavior: return whether the property is set
  • return false for non existing properties

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing isset($component->property).

See also https://www.php.net/manual/en/function.isset.php.

public boolean __isset ( $name )
$name string

The property name or the event name
return boolean

Whether the named property is set

 

                public function __isset($name)
{
    $getter = 'get' . $name;
    if (method_exists($this, $getter)) {
        return $this->$getter() !== null;
    }
    // behavior property
    $this->ensureBehaviors();
    foreach ($this->_behaviors as $behavior) {
        if ($behavior->canGetProperty($name)) {
            return $behavior->$name !== null;
        }
    }
    return false;
}
__set() public method

Defined in: yii\base\Component::__set()

Sets the value of a component property.

This method will check in the following order and act accordingly:

  • a property defined by a setter: set the property value
  • an event in the format of "on xyz": attach the handler to the event "xyz"
  • a behavior in the format of "as xyz": attach the behavior named as "xyz"
  • a property of a behavior: set the behavior property value

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing $component->property = $value;.

See also __get().

public void __set ( $name, $value )
$name string

The property name or the event name
$value mixed

The property value
throws yii\base\UnknownPropertyException

if the property is not defined
throws yii\base\InvalidCallException

if the property is read-only.

 

                public function __set($name, $value)
{
    $setter = 'set' . $name;
    if (method_exists($this, $setter)) {
        // set property
        $this->$setter($value);
        return;
    } elseif (strncmp($name, 'on ', 3) === 0) {
        // on event: attach event handler
        $this->on(trim(substr($name, 3)), $value);
        return;
    } elseif (strncmp($name, 'as ', 3) === 0) {
        // as behavior: attach behavior
        $name = trim(substr($name, 3));
        $this->attachBehavior($name, $value instanceof Behavior ? $value : Yii::createObject($value));
        return;
    }
    // behavior property
    $this->ensureBehaviors();
    foreach ($this->_behaviors as $behavior) {
        if ($behavior->canSetProperty($name)) {
            $behavior->$name = $value;
            return;
        }
    }
    if (method_exists($this, 'get' . $name)) {
        throw new InvalidCallException('Setting read-only property: ' . get_class($this) . '::' . $name);
    }
    throw new UnknownPropertyException('Setting unknown property: ' . get_class($this) . '::' . $name);
}
__unset() public method

Defined in: yii\base\Component::__unset()

Sets a component property to be null.

This method will check in the following order and act accordingly:

  • a property defined by a setter: set the property value to be null
  • a property of a behavior: set the property value to be null

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing unset($component->property).

See also https://www.php.net/manual/en/function.unset.php.

public void __unset ( $name )
$name string

The property name
throws yii\base\InvalidCallException

if the property is read only.

 

                public function __unset($name)
{
    $setter = 'set' . $name;
    if (method_exists($this, $setter)) {
        $this->$setter(null);
        return;
    }
    // behavior property
    $this->ensureBehaviors();
    foreach ($this->_behaviors as $behavior) {
        if ($behavior->canSetProperty($name)) {
            $behavior->$name = null;
            return;
        }
    }
    throw new InvalidCallException('Unsetting an unknown or read-only property: ' . get_class($this) . '::' . $name);
}
afterRun() public method (available since version 2.0.11)

This method is invoked right after a widget is executed.

The method will trigger the EVENT_AFTER_RUN event. The return value of the method will be used as the widget return value.

If you override this method, your code should look like the following:

public function afterRun($result)
{
    $result = parent::afterRun($result);
    // your custom code here
    return $result;
}
public mixed afterRun ( $result )
$result mixed

The widget return result.
return mixed

The processed widget result.

 

                public function afterRun($result)
{
    $event = new WidgetEvent();
    $event->result = $result;
    $this->trigger(self::EVENT_AFTER_RUN, $event);
    return $event->result;
}
attachBehavior() public method

Defined in: yii\base\Component::attachBehavior()

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 attached to this component by calling the yii\base\Behavior::attach() method.

See also detachBehavior().

public yii\base\Behavior attachBehavior ( $name, $behavior )
$name string

The name of the behavior.
$behavior string|array|yii\base\Behavior

The behavior configuration. This can be one of the following:
return yii\base\Behavior

The behavior object

 

                public function attachBehavior($name, $behavior)
{
    $this->ensureBehaviors();
    return $this->attachBehaviorInternal($name, $behavior);
}
attachBehaviors() public method

Defined in: yii\base\Component::attachBehaviors()

Attaches a list of behaviors to the component.

Each behavior is indexed by its name and should be a yii\base\Behavior object, a string specifying the behavior class, or an configuration array for creating the behavior.

See also attachBehavior().

public void attachBehaviors ( $behaviors )
$behaviors array

List of behaviors to be attached to the component

 

                public function attachBehaviors($behaviors)
{
    $this->ensureBehaviors();
    foreach ($behaviors as $name => $behavior) {
        $this->attachBehaviorInternal($name, $behavior);
    }
}
beforeRun() public method (available since version 2.0.11)

This method is invoked right before the widget is executed.

The method will trigger the EVENT_BEFORE_RUN event. The return value of the method will determine whether the widget should continue to run.

When overriding this method, make sure you call the parent implementation like the following:

public function beforeRun()
{
    if (!parent::beforeRun()) {
        return false;
    }

    // your custom code here

    return true; // or false to not run the widget
}
public boolean beforeRun ( )
return boolean

Whether the widget should continue to be executed.

 

                public function beforeRun()
{
    $event = new WidgetEvent();
    $this->trigger(self::EVENT_BEFORE_RUN, $event);
    return $event->isValid;
}
begin() public static method

Begins a widget.

This method creates an instance of the calling class. It will apply the configuration to the created instance. A matching end() call should be called later. As some widgets may use output buffering, the end() call should be made in the same view to avoid breaking the nesting of output buffers.

See also end().

public static static begin ( $config = [] )
$config array

Name-value pairs that will be used to initialize the object properties
return yii\base\Widget

The newly created widget instance

 

                public static function begin($config = [])
{
    $config['class'] = get_called_class();
    /* @var $widget Widget */
    $widget = Yii::createObject($config);
    self::$stack[] = $widget;
    return $widget;
}
behaviors() public method

Defined in: yii\base\Component::behaviors()

Returns a list of behaviors that this component should behave as.

Child classes may override this method to specify the behaviors they want to behave as.

The return value of this method should be an array of behavior objects or configurations indexed by behavior names. A behavior configuration can be either a string specifying the behavior class or an array of the following structure:

'behaviorName' => [
    'class' => 'BehaviorClass',
    'property1' => 'value1',
    'property2' => 'value2',
]

Note that a behavior class must extend from yii\base\Behavior. Behaviors can be attached using a name or anonymously. When a name is used as the array key, using this name, the behavior can later be retrieved using getBehavior() or be detached using detachBehavior(). Anonymous behaviors can not be retrieved or detached.

Behaviors declared in this method will be attached to the component automatically (on demand).

public array behaviors ( )
return array

The behavior configurations.

 

                public function behaviors()
{
    return [];
}
canGetProperty() public method

Defined in: yii\base\Component::canGetProperty()

Returns a value indicating whether a property can be read.

A property can be read if:

  • the class has a getter method associated with the specified name (in this case, property name is case-insensitive);
  • the class has a member variable with the specified name (when $checkVars is true);
  • an attached behavior has a readable property of the given name (when $checkBehaviors is true).

See also canSetProperty().

public boolean canGetProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name string

The property name
$checkVars boolean

Whether to treat member variables as properties
$checkBehaviors boolean

Whether to treat behaviors' properties as properties of this component
return boolean

Whether the property can be read

 

                public function canGetProperty($name, $checkVars = true, $checkBehaviors = true)
{
    if (method_exists($this, 'get' . $name) || $checkVars && property_exists($this, $name)) {
        return true;
    } elseif ($checkBehaviors) {
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canGetProperty($name, $checkVars)) {
                return true;
            }
        }
    }
    return false;
}
canSetProperty() public method

Defined in: yii\base\Component::canSetProperty()

Returns a value indicating whether a property can be set.

A property can be written if:

  • the class has a setter method associated with the specified name (in this case, property name is case-insensitive);
  • the class has a member variable with the specified name (when $checkVars is true);
  • an attached behavior has a writable property of the given name (when $checkBehaviors is true).

See also canGetProperty().

public boolean canSetProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name string

The property name
$checkVars boolean

Whether to treat member variables as properties
$checkBehaviors boolean

Whether to treat behaviors' properties as properties of this component
return boolean

Whether the property can be written

 

                public function canSetProperty($name, $checkVars = true, $checkBehaviors = true)
{
    if (method_exists($this, 'set' . $name) || $checkVars && property_exists($this, $name)) {
        return true;
    } elseif ($checkBehaviors) {
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canSetProperty($name, $checkVars)) {
                return true;
            }
        }
    }
    return false;
}
className() public static method
Deprecated since 2.0.14. On PHP >=5.5, use ::class instead.

Defined in: yii\base\BaseObject::className()

Returns the fully qualified name of this class.

public static string className ( )
return string

The fully qualified name of this class.

 

                public static function className()
{
    return get_called_class();
}
detachBehavior() public method

Defined in: yii\base\Component::detachBehavior()

Detaches a behavior from the component.

The behavior's yii\base\Behavior::detach() method will be invoked.

public yii\base\Behavior|null detachBehavior ( $name )
$name string

The behavior's name.
return yii\base\Behavior|null

The detached behavior. Null if the behavior does not exist.

 

                public function detachBehavior($name)
{
    $this->ensureBehaviors();
    if (isset($this->_behaviors[$name])) {
        $behavior = $this->_behaviors[$name];
        unset($this->_behaviors[$name]);
        $behavior->detach();
        return $behavior;
    }
    return null;
}
detachBehaviors() public method

Defined in: yii\base\Component::detachBehaviors()

Detaches all behaviors from the component.

public void detachBehaviors ( )

                public function detachBehaviors()
{
    $this->ensureBehaviors();
    foreach ($this->_behaviors as $name => $behavior) {
        $this->detachBehavior($name);
    }
}
end() public static method

Ends a widget.

Note that the rendering result of the widget is directly echoed out.

See also begin().

public static static end ( )
return yii\base\Widget

The widget instance that is ended.
throws yii\base\InvalidCallException

if begin() and end() calls are not properly nested

 

                public static function end()
{
    if (!empty(self::$stack)) {
        $widget = array_pop(self::$stack);
        $calledClass = get_called_class();
        if (Yii::$container->has($calledClass) && isset(Yii::$container->getDefinitions()[$calledClass]['class'])) {
            $calledClass = Yii::$container->getDefinitions()[$calledClass]['class'];
        }
        if (get_class($widget) === $calledClass) {
            /* @var $widget Widget */
            if ($widget->beforeRun()) {
                $result = $widget->run();
                $result = $widget->afterRun($result);
                echo $result;
            }
            return $widget;
        }
        throw new InvalidCallException('Expecting end() of ' . get_class($widget) . ', found ' . get_called_class());
    }
    throw new InvalidCallException('Unexpected ' . get_called_class() . '::end() call. A matching begin() is not found.');
}
ensureBehaviors() public method

Defined in: yii\base\Component::ensureBehaviors()

Makes sure that the behaviors declared in behaviors() are attached to this component.

public void ensureBehaviors ( )

                public function ensureBehaviors()
{
    if ($this->_behaviors === null) {
        $this->_behaviors = [];
        foreach ($this->behaviors() as $name => $behavior) {
            $this->attachBehaviorInternal($name, $behavior);
        }
    }
}
getBehavior() public method

Defined in: yii\base\Component::getBehavior()

Returns the named behavior object.

public yii\base\Behavior|null getBehavior ( $name )
$name string

The behavior name
return yii\base\Behavior|null

The behavior object, or null if the behavior does not exist

 

                public function getBehavior($name)
{
    $this->ensureBehaviors();
    return isset($this->_behaviors[$name]) ? $this->_behaviors[$name] : null;
}
getBehaviors() public method

Defined in: yii\base\Component::getBehaviors()

Returns all behaviors attached to this component.

public yii\base\Behavior[] getBehaviors ( )
return yii\base\Behavior[]

List of behaviors attached to this component

 

                public function getBehaviors()
{
    $this->ensureBehaviors();
    return $this->_behaviors;
}
getId() public method

Returns the ID of the widget.

public string|null getId ( $autoGenerate = true )
$autoGenerate boolean

Whether to generate an ID if it is not set previously
return string|null

ID of the widget.

 

                public function getId($autoGenerate = true)
{
    if ($autoGenerate && $this->_id === null) {
        $this->_id = static::$autoIdPrefix . static::$counter++;
    }
    return $this->_id;
}
getView() public method

Returns the view object that can be used to render views or view files.

The render() and renderFile() methods will use this view object to implement the actual view rendering. If not set, it will default to the "view" application component.

public yii\web\View getView ( )
return yii\web\View

The view object that can be used to render views or view files.

 

                public function getView()
{
    if ($this->_view === null) {
        $this->_view = Yii::$app->getView();
    }
    return $this->_view;
}
getViewPath() public method

Returns the directory containing the view files for this widget.

The default implementation returns the 'views' subdirectory under the directory containing the widget class file.

public string getViewPath ( )
return string

The directory containing the view files for this widget.

 

                public function getViewPath()
{
    $class = new ReflectionClass($this);
    return dirname($class->getFileName()) . DIRECTORY_SEPARATOR . 'views';
}
hasEventHandlers() public method

Defined in: yii\base\Component::hasEventHandlers()

Returns a value indicating whether there is any handler attached to the named event.

public boolean hasEventHandlers ( $name )
$name string

The event name
return boolean

Whether there is any handler attached to the event.

 

                public function hasEventHandlers($name)
{
    $this->ensureBehaviors();
    if (!empty($this->_events[$name])) {
        return true;
    }
    foreach ($this->_eventWildcards as $wildcard => $handlers) {
        if (!empty($handlers) && StringHelper::matchWildcard($wildcard, $name)) {
            return true;
        }
    }
    return Event::hasHandlers($this, $name);
}
hasMethod() public method

Defined in: yii\base\Component::hasMethod()

Returns a value indicating whether a method is defined.

A method is defined if:

  • the class has a method with the specified name
  • an attached behavior has a method with the given name (when $checkBehaviors is true).
public boolean hasMethod ( $name, $checkBehaviors = true )
$name string

The property name
$checkBehaviors boolean

Whether to treat behaviors' methods as methods of this component
return boolean

Whether the method is defined

 

                public function hasMethod($name, $checkBehaviors = true)
{
    if (method_exists($this, $name)) {
        return true;
    } elseif ($checkBehaviors) {
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->hasMethod($name)) {
                return true;
            }
        }
    }
    return false;
}
hasProperty() public method

Defined in: yii\base\Component::hasProperty()

Returns a value indicating whether a property is defined for this component.

A property is defined if:

  • the class has a getter or setter method associated with the specified name (in this case, property name is case-insensitive);
  • the class has a member variable with the specified name (when $checkVars is true);
  • an attached behavior has a property of the given name (when $checkBehaviors is true).

See also:

public boolean hasProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name string

The property name
$checkVars boolean

Whether to treat member variables as properties
$checkBehaviors boolean

Whether to treat behaviors' properties as properties of this component
return boolean

Whether the property is defined

 

                public function hasProperty($name, $checkVars = true, $checkBehaviors = true)
{
    return $this->canGetProperty($name, $checkVars, $checkBehaviors) || $this->canSetProperty($name, false, $checkBehaviors);
}
init() public method

Initializes the object.

This method is called at the end of the constructor. The default implementation will trigger an EVENT_INIT event.

public void init ( )

                public function init()
{
    parent::init();
    $this->trigger(self::EVENT_INIT);
}
off() public method

Defined in: yii\base\Component::off()

Detaches an existing event handler from this component.

This method is the opposite of on().

Note: in case wildcard pattern is passed for event name, only the handlers registered with this wildcard will be removed, while handlers registered with plain names matching this wildcard will remain.

See also on().

public boolean off ( $name, $handler = null )
$name string

Event name
$handler callable|null

The event handler to be removed. If it is null, all handlers attached to the named event will be removed.
return boolean

If a handler is found and detached

 

                public function off($name, $handler = null)
{
    $this->ensureBehaviors();
    if (empty($this->_events[$name]) && empty($this->_eventWildcards[$name])) {
        return false;
    }
    if ($handler === null) {
        unset($this->_events[$name], $this->_eventWildcards[$name]);
        return true;
    }
    $removed = false;
    // plain event names
    if (isset($this->_events[$name])) {
        foreach ($this->_events[$name] as $i => $event) {
            if ($event[0] === $handler) {
                unset($this->_events[$name][$i]);
                $removed = true;
            }
        }
        if ($removed) {
            $this->_events[$name] = array_values($this->_events[$name]);
            return true;
        }
    }
    // wildcard event names
    if (isset($this->_eventWildcards[$name])) {
        foreach ($this->_eventWildcards[$name] as $i => $event) {
            if ($event[0] === $handler) {
                unset($this->_eventWildcards[$name][$i]);
                $removed = true;
            }
        }
        if ($removed) {
            $this->_eventWildcards[$name] = array_values($this->_eventWildcards[$name]);
            // remove empty wildcards to save future redundant regex checks:
            if (empty($this->_eventWildcards[$name])) {
                unset($this->_eventWildcards[$name]);
            }
        }
    }
    return $removed;
}
on() public method

Defined in: yii\base\Component::on()

Attaches an event handler to an event.

The event handler must be a valid PHP callback. The following are some examples:

function ($event) { ... }         // anonymous function
[$object, 'handleClick']          // $object->handleClick()
['Page', 'handleClick']           // Page::handleClick()
'handleClick'                     // global function handleClick()

The event handler must be defined with the following signature,

function ($event)

where $event is an yii\base\Event object which includes parameters associated with the event.

Since 2.0.14 you can specify event name as a wildcard pattern:

$component->on('event.group.*', function ($event) {
    Yii::trace($event->name . ' is triggered.');
});

See also off().

public void on ( $name, $handler, $data = null, $append = true )
$name string

The event name
$handler callable

The event handler
$data mixed

The data to be passed to the event handler when the event is triggered. When the event handler is invoked, this data can be accessed via yii\base\Event::$data.
$append boolean

Whether to append new event handler to the end of the existing handler list. If false, the new handler will be inserted at the beginning of the existing handler list.

 

                public function on($name, $handler, $data = null, $append = true)
{
    $this->ensureBehaviors();
    if (strpos($name, '*') !== false) {
        if ($append || empty($this->_eventWildcards[$name])) {
            $this->_eventWildcards[$name][] = [$handler, $data];
        } else {
            array_unshift($this->_eventWildcards[$name], [$handler, $data]);
        }
        return;
    }
    if ($append || empty($this->_events[$name])) {
        $this->_events[$name][] = [$handler, $data];
    } else {
        array_unshift($this->_events[$name], [$handler, $data]);
    }
}
render() public method

Renders a view.

The view to be rendered can be specified in one of the following formats:

  • path alias (e.g. "@app/views/site/index");
  • absolute path within application (e.g. "//site/index"): the view name starts with double slashes. The actual view file will be looked for under the view path of the application.
  • absolute path within module (e.g. "/site/index"): the view name starts with a single slash. The actual view file will be looked for under the view path of the currently active module.
  • relative path (e.g. "index"): the actual view file will be looked for under $viewPath.

If the view name does not contain a file extension, it will use the default one .php.

public string render ( $view, $params = [] )
$view string

The view name.
$params array

The parameters (name-value pairs) that should be made available in the view.
return string

The rendering result.
throws yii\base\InvalidArgumentException

if the view file does not exist.

 

                public function render($view, $params = [])
{
    return $this->getView()->render($view, $params, $this);
}
renderFile() public method

Renders a view file.

public string renderFile ( $file, $params = [] )
$file string

The view file to be rendered. This can be either a file path or a path alias.
$params array

The parameters (name-value pairs) that should be made available in the view.
return string

The rendering result.
throws yii\base\InvalidArgumentException

if the view file does not exist.

 

                public function renderFile($file, $params = [])
{
    return $this->getView()->renderFile($file, $params, $this);
}
run() public method

Executes the widget.

public string|void run ( )
return string|void

The rendering result may be directly "echoed" or returned as a string

 

                public function run()
{
}
setId() public method

Sets the ID of the widget.

public void setId ( $value )
$value string

Id of the widget.

 

                public function setId($value)
{
    $this->_id = $value;
}
setView() public method

Sets the view object to be used by this widget.

public void setView ( $view )
$view yii\base\View

The view object that can be used to render views or view files.

 

                public function setView($view)
{
    $this->_view = $view;
}
trigger() public method

Defined in: yii\base\Component::trigger()

Triggers an event.

This method represents the happening of an event. It invokes all attached handlers for the event including class-level handlers.

public void trigger ( $name, yii\base\Event $event = null )
$name string

The event name
$event yii\base\Event|null

The event instance. If not set, a default yii\base\Event object will be created.

 

                public function trigger($name, Event $event = null)
{
    $this->ensureBehaviors();
    $eventHandlers = [];
    foreach ($this->_eventWildcards as $wildcard => $handlers) {
        if (StringHelper::matchWildcard($wildcard, $name)) {
            $eventHandlers[] = $handlers;
        }
    }
    if (!empty($this->_events[$name])) {
        $eventHandlers[] = $this->_events[$name];
    }
    if (!empty($eventHandlers)) {
        $eventHandlers = call_user_func_array('array_merge', $eventHandlers);
        if ($event === null) {
            $event = new Event();
        }
        if ($event->sender === null) {
            $event->sender = $this;
        }
        $event->handled = false;
        $event->name = $name;
        foreach ($eventHandlers as $handler) {
            $event->data = $handler[1];
            call_user_func($handler[0], $event);
            // stop further handling if the event is handled
            if ($event->handled) {
                return;
            }
        }
    }
    // invoke class-level attached handlers
    Event::trigger($this, $name, $event);
}
widget() public static method

Creates a widget instance and runs it.

The widget rendering result is returned by this method.

public static string widget ( $config = [] )
$config array

Name-value pairs that will be used to initialize the object properties
return string

The rendering result of the widget.
throws Throwable 

                public static function widget($config = [])
{
    ob_start();
    ob_implicit_flush(false);
    try {
        /* @var $widget Widget */
        $config['class'] = get_called_class();
        $widget = Yii::createObject($config);
        $out = '';
        if ($widget->beforeRun()) {
            $result = $widget->run();
            $out = $widget->afterRun($result);
        }
    } catch (\Exception $e) {
        // close the output buffer opened above if it has not been closed already
        if (ob_get_level() > 0) {
            ob_end_clean();
        }
        throw $e;
    } catch (\Throwable $e) {
        // close the output buffer opened above if it has not been closed already
        if (ob_get_level() > 0) {
            ob_end_clean();
        }
        throw $e;
    }
    return ob_get_clean() . $out;
}

Event Details

Hide inherited properties

EVENT_AFTER_RUN event of type yii\base\WidgetEvent (available since version 2.0.11)

An event raised right after executing a widget.

EVENT_BEFORE_RUN event of type yii\base\WidgetEvent (available since version 2.0.11)

An event raised right before executing a widget. You may set yii\base\WidgetEvent::$isValid to be false to cancel the widget execution.

EVENT_INIT event of type yii\base\Event (available since version 2.0.11)

An event that is triggered when the widget is initialized via init().