NAME
UI::Dialog::Util::MenuControl - A menu maker for dialog
SYNOPSIS
use UI::Dialog::Util::MenuControl;
my $tree = {
title => 'Conditinal behaviour',
entries => [
{
title => 'entry A (prework for B)',
function => \&doA,
condition => undef,
},
{
title => 'entry B',
function => \&doB,
condition => \&aWasCalled,
},
{
title => 'reset A (undo prework)',
function => \&resetA,
condition => \&aWasCalled,
},
{
title => 'has also submenus',
entries => [
{
title => 'sub b 1',
},
{
title => 'sub b 2',
},
]
},
],
};
my $menu_control = UI::Dialog::Util::MenuControl->new( menu => $tree );
$menu_control->run();To build a menu, you can nest nodes with the attributes
title function a reference to a function. condition a reference to a function given a boolean result whether to display the item or not entries array ref to further nodes context a 'self" for the called function
DESCRIPTION
It is an OO class to render a Dialog menu by a tree of array and hashes with specific form. a shell. It does not use curses and has no large dependencies.
REQUIRES
METHODS
new
$self->new();parameters
context context object wich can be used for all called procedures (self)
backend UI::Dialog Backend engine. E.g. CDialog (default), GDialog, KDialog, ...
backend_settings Values as hash transfered to backend constructor
menu Tree structure (see example above)
catch An error catching function, which retrieves the error if first param (only if 'try' used)dialog
$self->dialog();Holds the backend dialog system.
run
$self->run();Main loop method. Will return when the user selected the last exit field.
showMenu
$self->showMenu();Main control unit, but usually called by run(). If you call it by yourself, you have to build your own loop around.
Try a function
Normaly the application dies if inside a function call a die() will happen. But you can try a function if it dies, it wont leave the menu. Therefore you have to add the magic work "try " before the function. As with dialogs the user may hit "cancel", I recomment to throw an exception (die) if that happens to make a difference to just "not entering a value". But if this menu call that function directly, the menu might also die then.
...
function => 'try askForValue',
...As a try will eat all errors, you can handle them; Use 'catch' as parameter to point to an error handler function. This function will get the thrown error as first parameter.
...
function => 'try askForValue',
catch => 'showErrorWithDialog',
...The catch can also be globally set via constructor. So far catch can only take scalars describing a function in the same context as the rest. A coderef won't work. Errors in the catcher can't be handled and the menu will realy die.
Context
The context you can use globaly (via constructor) or in a node, can be used in different ways. It is an important feature to keep object oriented features, because the function call from a menu normaly does not know which object you want to use and usually you want to separate the menu from the working object.
...
our $objA = Local::UsecaseA->new();
my $tree = {
title => 'Conditinal behaviour',
entries => [
{
title => 'entry B',
function => \&doB,
condition => \&Local::UsecaseA::check,
context => $objA,
},
],
};In this example an object objA has been loaded before and provides a check() method. To run this check method in $objA context, you can tell a context to the node.
What does the absolute same:
my $tree = {
title => 'Conditinal behaviour',
entries => [
{
title => 'entry B',
function => \&doB,
condition => sub{ $objA->check() },
},
],
};But here a more elegant way:
...
our $objA = Local::UsecaseA->new();
my $tree = {
title => 'Conditinal behaviour',
entries => [
{
title => 'entry B',
function => 'doB( "hello" )', # it is a simple string. Also parameters possible.
condition => 'check', # called as method on $objA
},
],
};
my $menu_control = UI::Dialog::Util::MenuControl->new(
menu => $tree,
context => $objA, # Set the context for methods
);
$menu_control->run();Negative conditions
It is quite simple. Just add the magic word "not " or "!" in front of a condition.
...
function => 'prepareFolder',
condition => 'not isFolderPrepared',
...AUTHOR
Andreas Hernitscheck ahernit(AT)cpan.org
LICENSE
You can redistribute it and/or modify it under the conditions of LGPL.