mainwindow(3)

NAME

Tk::MainWindow - Root widget of a widget tree

SYNOPSIS

use Tk;
my $mw = MainWindow->new( ... options ... );
my $this = $mw->ThisWidget -> pack ;
my $that = $mw->ThatWidget;
...
MainLoop;

DESCRIPTION

Perl/Tk applications (which have windows associated with
them) create one or more MainWindows which act as the con tainers and parents of the other widgets.

Tk::MainWindow is a special kind of Toplevel widget. It is the root of a widget tree. Therefore "$mw->Parent" returns
"undef".

The default title of a MainWindow is the basename of the
script (actually the Class name used for options lookup,
i.e. with basename with inital caps) or 'Ptk' as the fall
back value. If more than one MainWindow is created or
several instances of the script are running at the same
time the string " #n" is appended where the number "n" is
set to get a unique value.

Unlike the standard Tcl/Tk's wish, perl/Tk allows you to
create several MainWindows. When the last MainWindow is destroyed the Tk eventloop exits (the eventloop is entered
with the call of "MainLoop"). Various resources (bindings,
fonts, images, colors) are maintained or cached for each
MainWindow, so each MainWindow consumes more resources
than a Toplevel. However multiple MainWindows can make
sense when the user can destroy them independently.

METHODS

You can apply all methods that a Toplevel widget accepts.

The method $w->MainWindow applied to any widget will return the MainWindow to which the widget belongs (the MainWindow belongs to itself).

MISSING

Documentation is incomplete. Here are some missing items
that should be explained in more detail:

· The new mechanism for MainWindows is slightly differ

ent to other widgets.

· There no explanation about what resources are bound to

a MainWindow (e.g., ClassInit done per MainWindow)

· Passing of command line options to override or augment

arguments of the "new" method (see Tk::CmdLine).

SEE ALSO

Tk::Toplevel Tk::CmdLine