Tk::Splashscreen - display a Splashscreen during program initialization.

Tk-Splashscreen documentation Contained in the Tk-Splashscreen distribution.

Index

Code Index:

NAME

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Tk::Splashscreen - display a Splashscreen during program initialization.

SYNOPSIS

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 $splash = $parent->Splashscreen(-opt => val, ... );

DESCRIPTION

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For programs that require large load times, it's a common practice to display a Splashscreen that occupies the user's attention. This Toplevel mega widget provides all the display, destroy and timing events. All you do it create the Splashscreen mega widget, populate it as you see fit, then invoke Splash() to display it and Destroy() to tear it down.

Important note: be sure to sprinkle update() calls throughout your initialization code so that any Splashscreen events are handled. Remember, the screen may be animated, or the user may be simply moving the Splashscreen about.

OPTIONS

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The following option/value pairs are supported:

-milliseconds

The minimum number of milliseconds the Splashscreen should remain on the screen. Default is 0, which means that the Splashscreen is destroyed as soon as Destroy() is called. Otherwise, Destroy() waits for the specified time interval to elapse before destroying the Splashscreen.

METHODS

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$splash->Splash([milliseconds]);

If milliseconds is specified, it's the minimum number of milliseconds the Splashscreen should remain on the screen. This value takes precedence over that specified on the Splashscreen constructor call.

$splash->Destroy([milliseconds]);

If milliseconds is specified, it's the minimum number of milliseconds the Splashscreen should remain on the screen. This value takes precedence over that specified on the Splash() call, which takes precedence over that specified during Splashscreen construction.

BINDINGS

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<ButtonPress-3>

Notifies the Splashscreen to set a mark for an impending move.

<ButtonRelease-3>

Moves the Splashscreen from the mark to the cursor's current position.

ADVERTISED WIDGETS

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Component subwidgets can be accessed via the Subwidget method. This mega widget has no advertised subwidgets. Instead, treat the widget reference as a Toplevel and populate it as desired.

EXAMPLE

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 $splash = $mw->Splashscreen;

 ... populate the Splashscreen toplevel as desired ...

 $splash->Splash(4000);

 ... program initialization ...

 $splash->Destroy;

AUTHOR

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Stephen.O.Lidie@Lehigh.EDU

Copyright (C) 2001 - 2002, Steve Lidie. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

KEYWORDS

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Splashscreen, Toplevel

Tk-Splashscreen documentation Contained in the Tk-Splashscreen distribution. 
$Tk::Splashscreen::VERSION = '1.0';

package Tk::Splashscreen;

use Tk qw/Ev/;
use Tk qw/:eventtypes/;
use Tk::waitVariableX;
use Tk::widgets qw/Toplevel/;
use base qw/Tk::Toplevel/;

Construct Tk::Widget 'Splashscreen';

sub Populate {
    my ($self, $args) = @_;

    $self->withdraw;
    $self->overrideredirect(1);

    $self->SUPER::Populate($args);

    $self->{ofx} = 0;           # X offset from top-left corner to cursor
    $self->{ofy} = 0;           # Y offset from top-left corner to cursor
    $self->{tm0} = 0;           # microseconds time widget was Shown

    $self->ConfigSpecs(
        -milliseconds => [qw/PASSIVE milliseconds Milliseconds 0/],
    );

    $self->bind('<ButtonPress-3>'   => [$self => 'b3prs', Ev('x'), Ev('y')]);
    $self->bind('<ButtonRelease-3>' => [$self => 'b3rls', Ev('X'), Ev('Y')]);

} # end Populate

# Object methods.

sub Destroy {


    my ($self, $millis) = @_;

    $millis = $self->cget(-milliseconds) unless defined $millis;
    my $t = Tk::timeofday;
    $millis = $millis - ( ($t - $self->{tm0}) * 1000 );
    $millis = 0 if $millis < 0;

    my $destroy_splashscreen = sub {
	$self->update;
	$self->after(100);	# ensure 100% of PB seen
	$self->destroy;
    };

    do { &$destroy_splashscreen; return } if $millis == 0;

    while ( $self->DoOneEvent (DONT_WAIT | TIMER_EVENTS)) {}

    $self->waitVariableX( [$millis, $destroy_splashscreen] );

} # end Destroy

sub Splash {

    my ($self, $millis) = @_;

    $millis = $self->cget(-milliseconds) unless defined $millis;
    $self->{tm0} = Tk::timeofday;
    $self->configure(-milliseconds => $millis);
    $self->Popup;

} # end_splash

# Private methods.

sub b3prs {
    my ($self, $x, $y) = @_;
    $self->{ofx} = $x;
    $self->{ofy} = $y;
} # end b3prs

sub b3rls {
    my($self, $X, $Y) = @_;
    $X -= $self->{ofx};
    $Y -= $self->{ofy};
    $self->geometry("+${X}+${Y}");
} # end b3rls

1;
__END__