=for comment based on iup-3.9 - http://www.tecgraf.puc-rio.br/iup/en/elem/iuplink.html
=head1 NAME
IUP::Link - [GUI element] label that displays an underlined clickable text
=head1 DESCRIPTION
Creates a label that displays an underlined clickable text. It is derived from L<IUP::Label|IUP::Label>.
=begin HTML
<p><img src="http://kmx.github.io/perl-iup/img-3.9/elem/iuplink.png"></p>
=end HTML
=head1 USAGE
=head2 CREATION - new() method
$link = IUP::Link->new( TITLE=>"Clickable text", URL=>'http://server.com/path/file.html' );
B<Returns:> the identifier of the created element, or C<undef> if an error occurs.
NOTE: You can pass to C<new()> other C<ATTRIBUTE=E<gt>'value'> or C<CALLBACKNAME=E<gt>\&func> pairs relevant
to this element - see L<IUP::Manual::02_Elements|IUP::Manual::02_Elements/"new()">.
=head2 ATTRIBUTES
For more info about concept of attributes (setting/getting values etc.)
see L<IUP::Manual::03_Attributes|IUP::Manual::03_Attributes>. Attributes specific to this element:
Inherits all attributes of the L<IUP::Label|IUP::Label>, but redefines a few attributes.
=over
=item L<FGCOLOR|IUP::Manual::03_Attributes/FGCOLOR>
Text color. Default: the global attribute LINKFGCOLOR.
=item B<URL>
URL Address or a special values "NO" (= not clickable).
=back
=head2 CALLBACKS
For more info about concept of callbacks (setting callback handlers etc.)
see L<IUP::Manual::04_Callbacks|IUP::Manual::04_Callbacks>. Callbacks specific to this element:
Inherits all callbacks of the L<IUP::Label|IUP::Label>.
=over
=item * L<ACTION|IUP::Manual::04_Callbacks/ACTION>
Action generated when the link is activated.
B<Callback handler prototype:>
sub action_handler {
my ($self, $url) = @_;
#...
}
B<$self:> reference to the element (IUP::Link) that activated the event
B<$url:> the destination address of the link
B<Returns:> IUP_CLOSE will be processed. If returns IUP_DEFAULT or it is
not defined, the L<Help|IUP::Manual::02_Elements/"Help()"> function will be called.
=back
=head1 NOTES
When the cursor is over the text, it is changed to the HAND cursor.
If the callback is not defined the L<Help|IUP::Manual::02_Elements/"Help()"> function is called with
the given URL.
The L<IUP::Label|IUP::Label> callbacks BUTTON_CB, ENTERWINDOW_CB and LEAVEWINDOW_CB
are used internally.
=head1 EXAMPLES
The element B<IUP::Link> is used in the following sample scripts:
=over
=item * L<0-basic/label.pl|https://metacpan.org/source/KMX/IUP-0.201/examples/0-basic/label.pl> - IUP::Label and IUP::Link example
=back
=head1 SEE ALSO
L<IUP::Label|IUP::Label>
The original doc: L<iuplink.html|http://www.tecgraf.puc-rio.br/iup/en/elem/iuplink.html>
=cut