NAME¶
Tk::MainWindow - Root widget of a widget tree
SYNOPSIS¶
use Tk;
my $mw = MainWindow->new( ... options ... );
my $this = $mw->ThisWidget -> pack ;
my $that = $mw->ThatWidget;
...
MainLoop;
DESCRIPTION¶
Perl/Tk applications (which have windows associated with them) create one or
more
MainWindows which act as the containers and parents of the other
widgets.
Tk::MainWindow is a special kind of Toplevel widget. It is the root of a
widget tree. Therefore "$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 fallback 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 different 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