NAME
XUL::Node::Event - a user interface event
SYNOPSYS
use XUL::Node;
# listening to existing widget
add_listener $button => Click => sub { print 'clicked!' };
# listening to widget in constructor, listener prints event value
TextBox(Change => sub { print shift->value });
# more complex listeners
add_listener $check_box => (Click => sub {
my $event = shift; # event is the only argument
print
'source: ' . $event->source, # source widget, a XUL::Node
', name: ' . $event->name, # Click
', checked: '. $event->checked; # Perl boolean
});
DESCRIPTION
Events are objects recieved as the only argument to a widget listener callback. You can interrogate them for information concerning the event.
Each type of widget has one or more event types that it fires. Buttons fire Click
, for example, but list boxes fire Select
.
Events from the UI can have side effects: a change in the textbox on the screen, requires that the value
attribute of the Perl textbox object change as well, to stay in sync. This happens automatically, and before listener code is run.
EVENT TYPES
All events have a name
and a source
. Each possible event name, can have additional methods for describing that specific event:
- Click
-
Button, ToolBarButton, MenuItem when inside a Menu, CheckBox, Radio
. Checkbox and radio events provide a methodchecked
, that returns the widget state as a boolean. - Change
-
TextBox
.value
will return the new textbox value. - Select
-
MenuList, ListBox, Button with TYPE_MENU
.selectedIndex
will return the index of the selected item in the widget. - Pick
-
ColorPicker
.color
will return the RGB value of the color selected.
SEE ALSO
Aspect::Library::Listenable