oracular (3) UI::Dialog::Screen::Menu.3pm.gz
NAME
UI::Dialog::Screen::Menu - wrapper to screen dialogs.
SYNOPSIS
use UI::Dialog::Screen::Menu;
# $d is an existing instance of UI::Dialog
my $screen = new UI::Dialog::Screen::Menu ( dialog => $d );
$screen->add_menu_item("This is the label", sub { print "Hello\n"; });
# $rv is 0 if the user canceled, 1 if any menu item was selected.
my $rv = $screen->run();
ABSTRACT
UI::Dialog::Screen::Menu is a helper class which enables a clean and modular code flow for menu driven
applications using UI::Dialog. Using callbacks assigned to menu items, a reactionary model to scripting
with UI::Dialog becomes rapidly easy.
DESCRIPTION
UI::Dialog::Screen::Menu is actually "external" to the UI::Dialog core usage. The class simply wraps
around an existing UI::Dialog instance for rendering a menu-driven flow of screens.
Using this class, you define a number of screen instances and assign callbacks to each of the menu items.
Once defined, simply call run() (or loop() to execute run() indefinitely). When a user selects one of the
menu items, the assigned function will be executed. From within those functions, simply call other
UI::Dialog::Screen::Menu instances and that's how you branch your user's experience from one screen to
the next. See the EXAMPLES
EXPORT
None
INHERITS
None
CONSTRUCTOR
new( %options )
EXAMPLE
# Have UI::Dialog::Screen::Menu use an existing UI::Dialog instance
# to render the user interface.
my $s = new( dialog => $d );
# Also accepts UI::Dialog constructor arguments, so that it can create
# it's own instance of UI::Dialog if none is provided.
my $s = new( title => 'Default Title', backtitle => 'Backtitle',
width => 65, height => 20, listheight => 5,
order => [ 'zenity', 'xdialog', 'gdialog' ] );
DESCRIPTION
This is the Class Constructor method. It accepts a list of key => value pairs and uses them as
the defaults when interacting with the various widgets.
RETURNS
A blessed object reference of the UI::Dialog::Screen::Menu class.
OPTIONS
The (...)'s after each option indicate the default for the option. An * denotes support by all the
widget methods on a per-use policy defaulting to the values decided during object creation.
dialog = UI::Dialog (undef)
debug = 0,1,2 (0)
order = [ zenity, xdialog, gdialog, kdialog, cdialog, whiptail, ascii ] (as indicated)
PATH = [ /bin, /usr/bin, /usr/local/bin, /opt/bin ] (as indicated)
backtitle = "backtitle" ('') *
title = "title" ('') *
beepbefore = 0,1 (0) *
beepafter = 0,1 (0) *
height = \d+ (20) *
width = \d+ (65) *
listheight = \d+ (5) *
STATE METHODS
run( )
EXAMPLE
my $rv = $s->run();
DESCRIPTION
Render the screen menu immediately. This method blocks until the user input has been received
and acted upon.
RETURNS
TRUE if the user selected an item from the menu, FALSE otherwise.
loop( )
EXAMPLE
$s->loop();
DESCRIPTION
Calls the run() method immediately. Once run() completes it's execution, the loop() decides
whether or not to display again. If the return value of run() is TRUE, the loop() will
continue. If the use pressed Cancel (or Escape) or any other action other than one of the menu
items; the loop() will end. The loop() will also end if the break_loop() method is called.
RETURNS
TRUE if the user selected an item from the menu, FALSE otherwise.
is_looping( )
EXAMPLE
if ($s->is_looping()) {
print "Currently in a UI::Dialog::Screen::Menu loop\n";
}
DESCRIPTION
Returns TRUE if the given screen is in a menu loop(), FALSE otherwise.
RETURNS
a single SCALAR.
break_loop( )
EXAMPLE
$s->break_loop();
DESCRIPTION
Flags the screen menu to stop looping. This does not close or otherwise clear the screen. This
simply flags the loop to exit at the end of it's current run.
RETURNS
None.
SCREEN METHODS
add_menu_item( )
EXAMPLE
my $index = $s->add_menu_item( "Menu Item Label", \%some_function );
DESCRIPTION
Append a new item to the menu list.
RETURNS
Returns the list index (starting from 0) of the item that was just appended to the list.
get_menu_items( )
EXAMPLE
my @items = $s->get_menu_items();
DESCRIPTION
Returns an array of hashrefs. Each hash contains a "label" and "func" key/value pairs.
RETURNS
An ARRAY.
del_menu_item( )
EXAMPLE
my $old_item = $d->del_menu_item( $index );
DESCRIPTION
Remove a specific item from the menu, addressed by it's list index (starting from 0), and
return the menu item as a hashref.
RETURNS
A HASH containing the 'label' and 'func' of the menu item that was just removed from the menu
list.
set_menu_item( )
EXAMPLE
# Modify the 'label' and 'func' for a specific menu item
my $original_item = $s->set_menu_item( $index, $label, $func );
# Modify just the label of a menu item
my $original_item = $s->set_menu_item( $index, $label, undef );
# Modify just the func of a menu item
my $original_item = $s->set_menu_item( $index, undef, $func );
# Effectively do nothing
my $original_item = $s->set_menu_item( $index, undef, undef );
DESCRIPTION
Modify the menu item addressed by the given index (starting from 0). If the 'label' and/or
'func' arguments are undef then the previous value is kept.
RETURNS
A HASH of the original values for the modified menu item.
EXAMPLE USAGE
The below example assumed that $d is an instances of UI::Dialog.
# Create our first screen
my $s1 = new UI::Dialog::Screen::Menu ( dialog => $d );
$s1->add_menu_item( "Just an option", \&some_function );
# Add a menu item that updates it's own label every time
# it is selected.
our $counter = 0;
$s1->add_menu_item
( "Counter: ".$counter,
sub {
my ($self,$dialog,$index) = @_;
$counter++;
$self->set_menu_item($index,"Counter: ".$counter, undef);
}
);
# Create a second screen
my $s2 = new UI::Dialog::Screen::Menu ( dialog => $d );
$s2->add_menu_item( "Another item", \&another_function );
# Link the second screen to an option of the first
$s1->add_menu_item( "Goto Screen 2", sub { $s2->loop(); } );
# Start a menu loop and actually display the first screen
$s1->loop();
Users can get to second menu from selecting the third item on the first menu screen. As long as the user
continues to select items from the second menu, it will continue to loop. If the user cancels the second
screen, the will return to the first which will itself continue to loop.
SEE ALSO
PERLDOC
UI::Dialog
UI::Dialog::GNOME
UI::Dialog::KDE
UI::Dialog::Console
UI::Dialog::Screen::Druid
UI::Dialog::Backend
UI::Dialog::Backend::ASCII
UI::Dialog::Backend::CDialog
UI::Dialog::Backend::GDialog
UI::Dialog::Backend::KDialog
UI::Dialog::Backend::Nautilus
UI::Dialog::Backend::Whiptail
UI::Dialog::Backend::XDialog
UI::Dialog::Backend::XOSD
UI::Dialog::Backend::Zenity
MAN FILES
dialog(1), whiptail(1), zenity(1), gdialog(1), Xdialog(1),
osd_cat(1), kdialog(1) and nautilus(1)
BUGS
Please email the author with any bug reports. Include the name of the module in the subject line.
AUTHOR
Kevin C. Krinke, <kevin@krinke.ca>
COPYRIGHT AND LICENSE
Copyright (C) 2004-2016 Kevin C. Krinke <kevin@krinke.ca> This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA