# Class yii\mongodb\i18n\MongoDbMessageSource

Inheritance | yii\mongodb\i18n\MongoDbMessageSource » yii\i18n\MessageSource » yii\base\Component » yii\base\BaseObject
Implements | yii\base\Configurable
Available since version | 2.0.5
Source Code | https://github.com/yiisoft/yii2-mongodb/blob/master/i18n/MongoDbMessageSource.php

MongoDbMessageSource extends yii\i18n\MessageSource and represents a message source that stores translated messages in MongoDB collection.

This message source uses single collection for the message translations storage, defined via $collection. Each entry in this collection should have 3 fields:

- language: string, translation language
- category: string, name translation category
- messages: array, list of actual message translations, in each element: the 'message' key is raw message name and 'translation' key - message translation.

For example:

    {
        "category": "app",
        "language": "de",
        "messages": {
            {
                "message": "Hello world!",
                "translation": "Hallo Welt!"
            },
            {
                "message": "The dog runs fast.",
                "translation": "Der Hund rennt schnell.",
            },
            ...
        },
    }

You also can specify 'messages' using source message as a direct BSON key, while its value holds the translation. For example:

    {
        "category": "app",
        "language": "de",
        "messages": {
            "Hello world!": "Hallo Welt!",
            "See more": "Mehr sehen",
            ...
        },
    }

However such approach is not recommended as BSON keys can not contain symbols like `.` or `$`.

## Public Properties

Hide inherited properties

Property | Type | Description | Defined By
--- | --- | --- | ---
$behaviors | yii\base\Behavior[] | List of behaviors attached to this component. | yii\base\Component
$cache | yii\caching\Cache|array|string | The cache object or the application component ID of the cache object. | yii\mongodb\i18n\MongoDbMessageSource
$cachingDuration | integer | The time in seconds that the messages can remain valid in cache. | yii\mongodb\i18n\MongoDbMessageSource
$collection | string|array | The name of the MongoDB collection, which stores translated messages. | yii\mongodb\i18n\MongoDbMessageSource
$db | yii\mongodb\Connection|array|string | The MongoDB connection object or the application component ID of the MongoDB connection. | yii\mongodb\i18n\MongoDbMessageSource
$enableCaching | boolean | Whether to enable caching translated messages | yii\mongodb\i18n\MongoDbMessageSource
$forceTranslation | boolean | Whether to force message translation when the source and target languages are the same. | yii\i18n\MessageSource
$sourceLanguage | string|null | The language that the original messages are in. | yii\i18n\MessageSource

## 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
attachBehavior() | Attaches a behavior to this component. | yii\base\Component
attachBehaviors() | Attaches a list of behaviors to the component. | yii\base\Component
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
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
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 DbMessageSource component. | yii\mongodb\i18n\MongoDbMessageSource
off() | Detaches an existing event handler from this component. | yii\base\Component
on() | Attaches an event handler to an event. | yii\base\Component
translate() | Translates a message to the specified language. | yii\i18n\MessageSource
trigger() | Triggers an event. | yii\base\Component

## Protected Methods

Hide inherited methods

Method | Description | Defined By
--- | --- | ---
loadMessages() | Loads the message translation for the specified language and category. | yii\mongodb\i18n\MongoDbMessageSource
loadMessagesFromDb() | Loads the messages from MongoDB. | yii\mongodb\i18n\MongoDbMessageSource
translateMessage() | Translates the specified message. | yii\i18n\MessageSource

## Events

Hide inherited events

Event | Type | Description | Defined By
--- | --- | --- | ---
EVENT_MISSING_TRANSLATION | yii\i18n\MissingTranslationEvent | An event that is triggered when a message translation is not found. | yii\i18n\MessageSource

## Property Details

Hide inherited properties

$cache public property

The cache object or the application component ID of the cache object. The messages data will be cached using this cache object. Note, that to enable caching you have to set $enableCaching to `true`, otherwise setting this property has no effect.

After the MongoDbMessageSource object is created, if you want to change this property, you should only assign it with a cache object.

This can also be a configuration array for creating the object.

See also:

- $cachingDuration
- $enableCaching

public yii\caching\Cache|array|string $cache = 'cache'
$cachingDuration public property

The time in seconds that the messages can remain valid in cache. Use 0 to indicate that the cached data will never expire.

See also $enableCaching.

public integer $cachingDuration = 0
$collection public property

The name of the MongoDB collection, which stores translated messages. This collection is better to be pre-created with fields 'category' and 'language' indexed.

public string|array $collection = 'message'
$db public property

The MongoDB connection object or the application component ID of the MongoDB connection.

After the MongoDbMessageSource object is created, if you want to change this property, you should only assign it with a MongoDB connection object.

This can also be a configuration array for creating the object.

public yii\mongodb\Connection|array|string $db = 'mongodb'
$enableCaching public property

Whether to enable caching translated messages

public boolean $enableCaching = false

## 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

Source code

                    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 ( )

Source code

                    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

Source code

                    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.

Source code

                    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

Source code

                    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.

Source code

                    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.

Source code

                    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);
    }

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:

- a yii\base\Behavior object
- a string specifying the behavior class
- an object configuration array that will be passed to Yii::createObject() to create the behavior object.

return | yii\base\Behavior | The behavior object

Source code

                    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

Source code

                    public function attachBehaviors($behaviors)
    {
        $this->ensureBehaviors();
        foreach ($behaviors as $name => $behavior) {
            $this->attachBehaviorInternal($name, $behavior);
        }
    }

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.

Source code

                    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

Source code

                    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

Source code

                    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.

Source code

                    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.

Source code

                    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 ( )

Source code

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

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 ( )

Source code

                    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

Source code

                    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

Source code

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

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.

Source code

                    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

Source code

                    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:

- canGetProperty()
- canSetProperty()

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

Source code

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

init() public method

Initializes the DbMessageSource component.

This method will initialize the $db property to make sure it refers to a valid DB connection. Configured $cache component would also be initialized.

public void init ( )
throws | yii\base\InvalidConfigException | if $db is invalid or $cache is invalid.

Source code

                    public function init()
    {
        parent::init();
        $this->db = Instance::ensure($this->db, Connection::className());
        if ($this->enableCaching) {
            $this->cache = Instance::ensure($this->cache, Cache::className());
        }
    }

loadMessages() protected method

Loads the message translation for the specified language and category.

If translation for specific locale code such as `en-US` isn't found it tries more generic `en`.

protected array loadMessages ( $category, $language )
$category | string | The message category
$language | string | The target language
return | array | The loaded messages. The keys are original messages, and the values are translated messages.

Source code

                    protected function loadMessages($category, $language)
    {
        if ($this->enableCaching) {
            $key = [
                __CLASS__,
                $category,
                $language,
            ];
            $messages = $this->cache->get($key);
            if ($messages === false) {
                $messages = $this->loadMessagesFromDb($category, $language);
                $this->cache->set($key, $messages, $this->cachingDuration);
            }
            return $messages;
        }
        return $this->loadMessagesFromDb($category, $language);
    }

loadMessagesFromDb() protected method

Loads the messages from MongoDB.

You may override this method to customize the message storage in the MongoDB.

protected array loadMessagesFromDb ( $category, $language )
$category | string | The message category.
$language | string | The target language.
return | array | The messages loaded from database.

Source code

                    protected function loadMessagesFromDb($category, $language)
    {
        $fallbackLanguage = substr($language, 0, 2);
        $fallbackSourceLanguage = substr($this->sourceLanguage, 0, 2);
        $languages = [
            $language,
            $fallbackLanguage,
            $fallbackSourceLanguage
        ];
        $rows = (new Query())
            ->select(['language', 'messages'])
            ->from($this->collection)
            ->andWhere(['category' => $category])
            ->andWhere(['language' => array_unique($languages)])
            ->all($this->db);
        if (count($rows) > 1) {
            $languagePriorities = [
                $language => 1
            ];
            $languagePriorities[$fallbackLanguage] = 2; // language key may be already taken
            $languagePriorities[$fallbackSourceLanguage] = 3; // language key may be already taken
            usort($rows, function ($a, $b) use ($languagePriorities) {
                $languageA = $a['language'];
                $languageB = $b['language'];
                if ($languageA === $languageB) {
                    return 0;
                }
                if ($languagePriorities[$languageA] < $languagePriorities[$languageB]) {
                    return +1;
                }
                return -1;
            });
        }
        $messages = [];
        foreach ($rows as $row) {
            foreach ($row['messages'] as $key => $value) {
                // @todo drop message as key specification at 2.2
                if (is_array($value)) {
                    $messages[$value['message']] = $value['translation'];
                } else {
                    $messages[$key] = $value;
                }
            }
        }
        return $messages;
    }

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

Source code

                    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.

Source code

                    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]);
        }
    }

translate() public method

Defined in: yii\i18n\MessageSource::translate()

Translates a message to the specified language.

Note that unless $forceTranslation is true, if the target language is the same as the source language, the message will NOT be translated.

If a translation is not found, a missingTranslation event will be triggered.

public string|boolean translate ( $category, $message, $language )
$category | string | The message category
$message | string | The message to be translated
$language | string | The target language
return | string|boolean | The translated message or false if translation wasn't found or isn't required

Source code

                    public function translate($category, $message, $language)
    {
        if ($this->forceTranslation || $language !== $this->sourceLanguage) {
            return $this->translateMessage($category, $message, $language);
        }
        return false;
    }

translateMessage() protected method

Defined in: yii\i18n\MessageSource::translateMessage()

Translates the specified message.

If the message is not found, a missingTranslation event will be triggered. If there is an event handler, it may provide a fallback translation. If no fallback translation is provided this method will return `false`.

protected string|boolean translateMessage ( $category, $message, $language )
$category | string | The category that the message belongs to.
$message | string | The message to be translated.
$language | string | The target language.
return | string|boolean | The translated message or false if translation wasn't found.

Source code

                    protected function translateMessage($category, $message, $language)
    {
        $key = $language . '/' . $category;
        if (!isset($this->_messages[$key])) {
            $this->_messages[$key] = $this->loadMessages($category, $language);
        }
        if (isset($this->_messages[$key][$message]) && $this->_messages[$key][$message] !== '') {
            return $this->_messages[$key][$message];
        } elseif ($this->hasEventHandlers(self::EVENT_MISSING_TRANSLATION)) {
            $event = new MissingTranslationEvent([
                'category' => $category,
                'message' => $message,
                'language' => $language,
            ]);
            $this->trigger(self::EVENT_MISSING_TRANSLATION, $event);
            if ($event->translatedMessage !== null) {
                return $this->_messages[$key][$message] = $event->translatedMessage;
            }
        }
        return $this->_messages[$key][$message] = false;
    }

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.

Source code

                    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);
    }