=for comment based on iup-3.5 - http://www.tecgraf.puc-rio.br/iup/en/elem/iupzbox.html

=head1 NAME

IUP::Zbox - [GUI element] container for composing elements in hidden layers with only one layer visible


Creates a void container for composing elements in hidden layers with
only one layer visible. It is a box that piles up the children it
contains, only the one child is visible.

It does not have a native representation.

Zbox works by changing the VISIBLE attribute of its children, so if any
of the grand children has its VISIBLE attribute directly defined then
Zbox will NOT change its state.

=head1 USAGE

=head2 CREATION - new() method

 #standard way
 my $zbox = IUP::Zbox->new( child=>[$elem1, $elem2], ANYATTRIBUTE=>'any value' );
 #or with just a single child
 my $zbox = IUP::Zbox->new( child=>$elem, ANYATTRIBUTE=>'any value' );
 #or with just 1 parameter (arrayref)
 my $zbox = IUP::Zbox->new( [$elem1, $elem2] );
 #or with just 1 parameter (reference to child elements)
 my $zbox = IUP::Zbox->new( $elem );

B<child:> (named parameter) List of the references to elements (or just a single element) that
will be placed in the box. Can be C<undef>.

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()">.


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:



I<(non inheritable)>

Defines the alignment of the visible
child. Possible values:

 "NE", "SE", "NW", "SW",

Default: "NW".

=item L<EXPAND|IUP::Manual::03_Attributes/EXPAND>

I<(non inheritable)>

The default value is "YES".

=item L<FLOATING|IUP::Manual::03_Attributes/FLOATING>

I<(non inheritable, at children only)>

If a child has FLOATING=YES then its size and position
will be ignored by the layout processing. Default: "NO". 

=item B<VALUE>

I<(non inheritable)>

The visible child. The value passed must be the perl reference or name of one of the children contained in the zbox.

To associate a name to element use L<SetName|/"SetName()"> or C<< name=>'ElemName' >> named parameter of L<new()|/"new()"> constructor.

When the value is changed the selected child is made visible and all
other children are made invisible, regardless their previous visible state.


I<(non inheritable)>

The visible child accessed by its
handle. The value passed must be the handle of a child contained in the
zbox. When the zbox is created, the first element inserted is set as
the visible child. 


I<(non inheritable)>

The visible child accessed by its
position. The value passed must be the index of a child contained in
the zbox, starting at 0. When the zbox is created, the first element
inserted is set as the visible child. 

=item L<SIZE|IUP::Manual::03_Attributes/SIZE> / L<RASTERSIZE|IUP::Manual::03_Attributes/RASTERSIZE> (non inheritable)

The default size is the smallest size that fits its largest child. All
child elements are considered even invisible ones, except when
FLOATING=YES in a child.

=item B<WID>


Returns -1 if mapped.


The following L<common attributes|IUP::Manual::03_Attributes/Common Attributes> are also accepted:


=item * L<FONT|IUP::Manual::03_Attributes/FONT>,


=head1 NOTES

The box can be created with no elements and be dynamic filled using
L<Append|IUP::Manual::02_Elements/"Append()"> or L<Insert|IUP::Manual::02_Elements/"Insert()">.


The element B<IUP::Zbox> is used in the following sample scripts:


=item * L<0-basic/zbox.pl|https://metacpan.org/source/KMX/IUP-0.305/examples/0-basic/zbox.pl> - IUP::Zbox example


=head1 SEE ALSO

L<IUP::Hbox|IUP::Hbox>, L<IUP::Vbox|IUP::Vbox>

The original doc: L<iupzbox.html|http://www.tecgraf.puc-rio.br/iup/en/elem/iupzbox.html>