NAME

HTML::DOM::Event - A Perl class for HTML DOM Event objects

SYNOPSIS

use HTML::DOM::Event ':all'; # get constants

use HTML::DOM;
$doc=new HTML::DOM;

$event = $doc->createEvent;
$event->initEvent(
    'click', # type
     1,      # whether it propagates up the hierarchy
     0,      # whether it can be cancelled
);
# OR:
$event->init(
    type => 'click',
    propagates_up => 1,
    cancellable => 0,
);

$doc->body->dispatchEvent($event); # fake event (run the handlers)
$doc->body->trigger_event($event); # real event

DESCRIPTION

This class provides event objects for HTML::DOM, which objects are passed to event handlers when they are triggered. It implements the W3C DOM's Event interface and serves as a base class for more specific event classes.

METHODS

DOM Attributes

These are all read-only and ignore their arguments.

type

The type, or name, of the event, without the 'on' prefix that HTML attributes have; e.g., 'click'.

target

This returns the node on which the event occurred. It only works during event propagation.

currentTarget

The returns the node whose handler is currently being called. (The event might have been triggered on one of its child nodes.) This also works only during event propagation.

eventPhase

Returns one of the constants listed below. This only makes sense during event propagation.

bubbles

This attribute returns a list of Bubble objects, each of which has a diameter and a wobbliness, which can be retrieved by the corresponding get_* methods. :-)

Actually, this strangely-named method returns true if the event propagates up the hierarchy after triggering event handlers on the target.

cancelable

Returns true or false.

timeStamp

Returns the time at which the event object was created as returned by Perl's built-in time function.

Other DOM Methods

initEvent ( $name, $propagates_up, $cancelable )

This initialises the event object. $propagates_up is whether the event should trigger handlers of parent nodes after the target node's handlers have been triggered. $cancelable determines whether preventDefault has any effect.

stopPropagation

If this is called, no more event handlers will be triggered.

preventDefault

If this is called and the event object is cancelable, HTML::DOM::EventTarget's dispatchEvent method will return false, indicating that the default action is not to be taken.

Non-DOM Methods

init

This is a nice alternative to initEvent. It takes named args:

$event->init(
    type => 'click',
    propagates_up => 1,
    cancellable => 1,
);

and returns the $event itself, so you can write:

$node->dispatchEvent( $doc->createEvent(...)->init(...) );

It also accepts target as an argument. This allows you to trigger weird events that have the target set to some object other than the actual target. (dispatchEvent will not set the target if it is already set.)

cancelled

Returns true if preventDefault has been called.

propagation_stopped

Returns true if stopPropagation has been called.

EXPORTS

The following node type constants are exportable, individually or with ':all':

CAPTURING_PHASE (1)

AT_TARGET (2)

BUBBLING_PHASE (3)

SEE ALSO

HTML::DOM

HTML::DOM::Event::UI

HTML::DOM::Event::UI::Mouse

HTML::DOM::Node