NAME Term::Menus - Create Powerful Terminal, Console and CMD Enviroment Menus SYNOPSIS "use Term::Menus;" see METHODS section below DESCRIPTION Term::Menus allows you to create powerful Terminal, Console and CMD environment menus. Any perl script used in a Terminal, Console or CMD environment can now include a menu facility that includes sub-menus, forward and backward navigation, single or multiple selection capabilities, dynamic item creation and customized banners. All this power is simple to implement with a straight forward and very intuitive configuration hash structure that mirrors the actual menu architechture needed by the application. A separate configuration file is optional. Term::Menus is cross platform compatible. Term::Menus was initially conceived and designed to work seemlessly with the perl based Network Process Automation Utility Module called Net::FullAuto (Available in CPAN :-) - however, it is not itself dependant on other Net::FullAuto components, and will work with *any* perl script/application. Reasons to use this module are: * You have a list (or array) of items, and wish to present the user a simple CMD enviroment menu to pick a single item and return that item as a scalar (or simple string). Example: use Term::Menus; my @list=('First Item','Second Item','Third Item'); my $banner=" Please Pick an Item:"; my $selection=&pick(\@list,$banner); print "SELECTION = $selection\n"; The user sees ==> Please Pick an Item: 1 First Item 2 Second Item 3 Third Item (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 2 >----------------------------------- The user sees ==> SELECTION = Second Item * You have a large list of items and need scrolling capability: use Term::Menus; my @list=`ls -1 /bin`; my $banner=" Please Pick an Item:"; my $selection=&pick(\@list,$banner); print "SELECTION = $selection\n"; The user sees ==> Please Pick an Item: 1 arch 2 ash 3 awk 4 basename 5 bash 6 cat 7 chgrp 8 chmod 9 chown 10 cp a. Select All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: ---------------------------------------- Please Pick an Item: 11 cpio 12 csh 13 cut 14 date 15 dd 16 df 17 echo 18 ed 19 egrep 20 env a. Select All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 14 >----------------------------------- The user sees ==> SELECTION = date * You need to select multiple items and return the selected list: use Term::Menus; my %Menu_1=( Item_1 => { Text => "/bin Utility - ]Convey[", Convey => [ `ls -1 /bin` ], }, Select => 'Many', Banner => "\n Choose a /bin Utility :" ); my @selections=&Menu(\%Menu_1); print "SELECTIONS = @selections\n"; The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 3 >----------------------------------- --< 7 >----------------------------------- The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash * 3 /bin Utility - awk 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat * 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< f >----------------------------------- The user sees ==> SELECTIONS = /bin Utility - awk /bin Utility - chgrp * You need sub-menus: use Term::Menus; my %Menu_2=( Name => 'Menu_2', Item_1 => { Text => "]Previous[ is a ]Convey[ Utility", Convey => [ 'Good','Bad' ] }, Select => 'One', Banner => "\n Choose an Answer :" ); my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => \%Menu_2, }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my $selection=&Menu(\%Menu_1); print "\n SELECTION=$selection\n"; The user sees ==> Choose a /bin Utility : 1. /bin Utility - arch 2. /bin Utility - ash 3. /bin Utility - awk 4. /bin Utility - basename 5. /bin Utility - bash 6. /bin Utility - cat 7. /bin Utility - chgrp 8. /bin Utility - chmod 9. /bin Utility - chown 10. /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 5 >----------------------------------- Choose an Answer : 1 bash is a Good Utility 2 bash is a Bad Utility (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 1 >----------------------------------- The user sees ==> SELECTIONS = bash is a Good Utility * You have a large amount of text, or instructional information, and want a *banner only screen* that displays the banner only (no selections) and that moves to the next screen/menu with just a press of the ENTER key. Yet, you want to preserve selections from earlier menus, and/or return to more menus after user completes reading the banner only screens. You can also navigate backwards and forwards through these screens. use Term::Menus: my %Menu_1=( Name => 'Menu_1', Banner => "\n This is a BANNER ONLY display." ); &Menu(\%Menu_1); The user sees ==> This is a BANNER ONLY display. ([ESC] to Quit) Press ENTER to continue ... * You want to use perl subroutines to create the text items and/or banner: use Term::Menus; sub create_items { my $previous=shift; my @textlines=(); push @textlines, "$previous is a Good Utility"; push @textlines, "$previous is a Bad Utility"; return @textlines; ## return value must be an array ## NOT an array reference } sub create_banner { my $previous=shift; return "\n Choose an Answer for $previous :" ## return value MUST be a string for banner } my %Menu_2=( Name => 'Menu_2', Item_1 => { Text => "]Convey[", Convey => "create_items(]Previous[)", }, Select => 'One', Banner => "create_banner(]Previous[)", ); my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => \%Menu_2, }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my @selection=&Menu(\%Menu_1); print "\n SELECTION=@selection\n"; The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 5 >----------------------------------- Choose an Answer for bash : 1 bash is a Good Utility 2 bash is a Bad Utility (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 1 >----------------------------------- The user sees ==> SELECTION = bash is a Good Utility * You want to use anonymous subroutines to create the text items and/or banner (see the more detailed treatment of anonymous subroutines and Term::Menus macros in a later section of this documentation): use Term::Menus; my $create_items = sub { my $previous=shift; my @textlines=(); push @textlines, "$previous is a Good Utility"; push @textlines, "$previous is a Bad Utility"; return \@textlines; ## return value must an array reference }; my $create_banner = sub { my $previous=shift; return "\n Choose an Answer for ]Previous[ :" ## return value MUST be a string for banner }; my %Menu_2=( Name => 'Menu_2', Item_1 => { Text => "]Convey[", Convey => $create_items->(']Previous['), # Subroutine executed # at runtime by Perl # and result is passed # to Term::Menus. # Do not use this argument # construct with Result => # elements because only Menu # blocks or subroutines can # be passed. (Unless the # return item is itself # a Menu configuration # block [HASH] or an # anonymous subroutine # [CODE]) }, Select => 'One', Banner => $create_banner, # Perl passes sub itself at runtime and # execution is carried out by Term::Menus. ); my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => \%Menu_2, }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my @selection=&Menu(\%Menu_1); print "\n SELECTION=@selection\n"; The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 5 >----------------------------------- Choose an Answer for bash : 1 bash is a Good Utility 2 bash is a Bad Utility (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 1 >----------------------------------- The user sees ==> SELECTION = bash is a Good Utility Usage questions should be directed to the Usenet newsgroup comp.lang.perl.modules. Contact me, Brian Kelly , if you find any bugs or have suggestions for improvements. What To Know Before Using * There are two methods available with Term::Menus - &pick() and &Menu(). "&Menu()" uses "&pick()" - you can get the same results using only "&Menu()". However, if you need to simply pick one item from a single list - use "&pick()". The syntax is simpler, and you'll write less code. ;-) * You'll need to be running at least Perl version 5.002 to use this module. METHODS pick - create a simple menu $pick = &pick ($list|\@list|['list',...],[$Banner]); Where *$list* is a variable containing an array or list reference. This argument can also be a escaped array (sending a reference) or an anonymous array (which also sends a reference). *$Banner* is an optional argument sending a customized Banner to top the simple menu - giving instructions, descriptions, etc. The default is "Please Pick an Item:" Menu - create a complex Menu $pick = &Menu ($list|\@list|['list',...],[$Banner]); Where *$pick* is a variable containing an array or list reference of the pick or picks. @picks = &Menu ($Menu_1|\%Menu_1|{ Name => 'Menu_1' }); Where *$Menu_1* is a hash reference to the top level Menu Configuration Hash Structure. Menu Configuration Hash Structures These are the building blocks of the overall Menu architecture. Each hash structure represents a *menu screen*. A single menu layer, has only one hash structure defining it. A menu with a single sub-menu will have two hash structures. The menus connect via the "Result" element of an *Item* - "Item_1" - hash structure in parent menu %Menu_1: my %Menu_2=( Name => 'Menu_2', Item_1 => { Text => "]Previous[ is a ]Convey[ Utility", Convey => [ 'Good','Bad' ] }, Select => 'One', Banner => "\n Choose an Answer :" ); my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => \%Menu_2, }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); Menu Component Elements Each Menu Configuration Hash Structure consists of elements that define and control it's behavior, appearance, constitution and purpose. An element's syntax is as you would expect it to be in perl - a key string pointing to an assocaited value: "key => value". The following items list supported key names and ther associated value types: * Display => 'Integer' The *Display* key is an *optional* key that determines the number of Menu Items that will be displayed on each screen. This is useful when the items are multi-lined, or the screen size is bigger or smaller than the default number utilizes in the most practical fashion. The default number is 10. Display => 15, * Name => 'Char String consisting of ASCII Characters' The *Name* key provides a unique identifier to each Menu Structure. This element is not "strictly" required for most Menu construts to function properly. Term::Menus goes to great lengths to discover and utilize the Menu's name provided on the left side of the equals character of a Menu block using the following construct: my %MenuName=( [ Menu Contents Here ] ); In the above example, the Menu name is "MenuName". Most of the time Term::Menus will discover this name successfully, affording the user or Menu developer one less requirement to worry about. Allowing Term::Menus to discover this name will cut down on opportunities for coding errors (and we all have enough of those already). HOWEVER, there are "edge cases" and more complex Menu constructs that will prevent Term::Menus from accurately discovering this name. Therefore, it is recommended and is considered a "best practice" to always explicitly "Name" Menu blocks as follows: my %MenuName=( Name => 'MenuName', [ Menu Contents Here ] ); Be careful to always use the SAME NAME for the Name element as for the Menu block itself. This can be a source of error, especially when one is using Macros that reference Menu Names explicitly (So be CAREFUL!) One case where the Name element must ALWAYS be used (if one wishes to reference that Menu with an explicit Named Macro) is when creating anonymous Menu blocks to feed directly to Result elements: my %ContainingMenu=( Name => 'ContainingMenu', Item_1 => { Text => "Some Text", Result => { Name => "Anonymous_Menu", # MUST use "Name" element # if planning to use # explicit Macros [ Menu Contents Here ] }, }, ); * Item_ => { Item Configuration Hash Structure } The *Item_* elements define customized menu items. There are essentially two methods for creating menu items: The *Item_* elements, and the "]Convey[" macro (described later). The difference being that the "]Convey[" macro turns an Item Configuration Hash into an Item *Template* -> a powerful way to *Item*-ize large lists or quantities of data that would otherwise be difficult - even impossible - to anticipate and cope with manually. Item_1 => { Text => 'Item 1' }, Item_2 => { Text => 'Item 2' }, Items created via "]Convey[" macros have two drawbacks: * They all have the same format. * They all share the same "Result" element. The syntax and usage of *Item_* elements is important and extensive enough to warrant it's own section. See *Item Configuration Hash Structures* below. * Select => 'One' --or-- 'Many' The MENU LEVEL *Select* element determines whether this particular menu layer allows the selection of multiple items - or a single item. The default is 'One'. Select => 'Many', * Banner => 'Char String consisting of ASCII Characters' or anonymous subroutine or subroutine reference for generating dynamic banners. The *Banner* element provides a customized descriptive header to the menu. *$Banner* is an optional element - giving instructions, descriptions, etc. The default is "Please Pick an Item:" Banner => "The following items are for selection,\n". "\tEnjoy the Experience!", --or-- Banner => sub { }, --or-- my $create_banner = sub { }, Banner => $create_banner, Creating a reference to a Banner subroutine enables the sharing of Banner generation code between multiple Menus. NOTE: Macros (like "]Previous[" ) *can* be used in Banners! :-) ( See Item Configuration Macros below ) Item Configuration Hash Structures Each Menu Item can have an independant configurtion. Each Menu Configuration Hash Structure consists of elements that define and control it's behavior, appearance, constitution and purpose. An element's syntax is as you would expect it to be in perl - a key string pointing to an assocaited value: key => value. The following items list supported key names and ther associated value types: * Text => 'Char String consisting of ASCII Characters' The *Text* element provides a customized descriptive string for the Item. It is the text the user will see displayed, describing the selection. Text => 'This is Item_1', * Convey => [ List ] --or-- @List --or-- $Scalar --or-- 'ASCII String' --or-- Anonymous Subroutine --or-- Subroutine Reference --or-- Ordinary Subroutine (*Ordinary* subroutine calls need to be surrounded by quotes. DO NOT use quotes with anonymous subroutine calls or ones called with a reference!) The *Convey* element has a twofold purpose; it provides for the contents of the "]Convey[" macro, and defines or contains the string or result that is passed on to child menus - if any. Use of this configuration element is *optional*. If "Convey" is not a list, then it's value is passed onto child menus. If "Convey" *is* a list, then the Item selected is passed onto the children - if any. It is important to note, *when used*, that only the resulting *Convey* string - *NOT* the the Item "Text" value or string, is conveyed to child menus. When the "Convey" element is not used, the full Item "Text" value is conveyed to the children - if any. However, the full contents of the "Text" element is *returned* as the *Result* of the operation when the user completes all menu activity. See the *Macro* section below for more information. Convey => [ `ls -1` ], NOTE: When using anonymous subroutines or subroutine references, there may be situations where code populating the Convey item encounters an error or gets data that is empty or unsatisfactory for some reason, and there is a need to print a message or write to a log or send an alert, and then return from this routine to an earlier menu. To force a return to a parent menu (assuming there is one) from a subroutine assigned to a Convey element, just return '<' from the subroutine. To return to any ancestor Menu in the stack, return this macro from the subroutine: "{Menu_Name}<" :-) * Default => 'Char String' --or-- Perl regular expression - qr/.../ The *Default* element provides a means to pre-select certain elements, as if the items were selected by the user. This can be done with two constructs - simple string or pre-compiled regular expression. Note: The "Default" element is available only when the "Select" element is set to 'Many' - "Select =" 'Many',> Default => 'base|chown', Default => qr/base|chown/i, The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk * 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod * 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: * Select => 'One' --or-- 'Many' The ITEM LEVEL *Select* element provides a means to inform Term::Menus that the specific items of a single ITEM BLOCK (as opposed to full menu) are subject to multiple selecting - or just single selection. This is useful in particular for Directory Tree navigation - where files can be multi-selected (or tagged), yet when a directory is selectedi, it forces an immediate navigation and new menu - showing the contents of the just selected directory. NOTE: See the RECURSIVELY CALLED MENUS section for more information. Select => 'More', The user sees ==> d 1 bin d 2 blib d 3 dist d 4 inc d 5 lib d 6 Module d 7 t 8 briangreat2.txt * 9 ChangeLog 10 close.perl a. Select All f. FINISH ___ 49 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: * Exclude => 'Char String' --or-- Perl regular expression - qr/.../ The *Exclude* element provides a means to remove matching elements from the Menu seen by the user. This element is useful only when the "]Convey[" macro is used to populate items. This can be done with two constructs - simple string or pre-compiled regular expression. Exclude => 'base|chown', Exclude => qr/base|chown/i, * Include => 'Char String' --or-- Perl regular expression - qr/.../ The *Include* element provides a means to create items filtered from a larger list of potential items available via the "]Convey[" macro. This element is useful only when the "]Convey[" macro is used to populate items. The "Exclude" element can be used in conjunction with "Include" to further refine the final list of items used to construct the menu. The "Include" element - when used - always takes presidence, and the "Exclude" will be used only on the "Include" filtered results. This element can be used with two value constructs - simple string or pre-compiled regular expression. Include => 'base|chown', Include => qr/base|chown/i, * Result => \%Menu_2 --or -- "&any_method()", * *Result* is an *optional* element that also has two important uses: * For selecting the child menu next in the chain of operation and conveyance, Result => \%Menu_2, --or-- * For building customized method arguements using "&Menu()"'s built-in macros. * Result => "&any_method($arg1,\"]Selected[\",\"]Previous[\")", NOTE: *ALWAYS* be sure to surround the subroutine or method calling syntax with DOUBLE QUOTES. (You can use single quotes if you don't want interpolation). Quotes are necessary because you're telling "&Menu()" - *not* Perl - what method you want invoked. "&Menu()" won't invoke the method until after all other processing - where Perl will try to invoke it the first time it encounters the line during runtime - lo----ng before a user gets a chance to see or do *anything*. BUT - be sure *NOT* to use quotes when assigning a child menu reference to the "Result" value. Again, *Result* is an *optional* element. The default behavior when "Result" is omitted from the Item Configuration element, is for the selection to be returned to the "&Menu()"'s calling script/module/app. If the "Select" element was set to 'One', then that item is returned regardless of whether the Perl structure receiving the output is an array or scalar. If there were multiple selections - i.e., "Select" is set to 'Many' - then, depending on what structure is set for receiving the output, will determine whether "&Menu()" returns a list (i.e. - array), or *reference* to an array. Item Configuration Macros Each Menu Item can utilize a very powerful set of configuration *Macros*. These constructs principally act as purveyors of information - from one menu to another, from one element to another. There are currently three available Macros: * ]Convey[ "]Convey[" is used in conjunction with the *Convey* element (described) earlier. It's purpose to "convey" or transport or carry a list item associated with the "Convey" element - and replace the "]Convey[" Macro in the "Text" element value with that list item. The *Convey* mechanism utilizing the "Convey" Macro is essentially an *Item multiplier*. The entire contents of the list associated with the *Convey* element will be turned into it's own "Item" when the menu is displayed. Both ordinary and anonymous subroutines can be use to dynamically generate *Convey* lists. (With *]Convey[*, macros can be used only as subroutine arguments or in the body of anonymous subroutines - see other examples.) use Term::Menus; my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => \%Menu_2, }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my @selections=&Menu(\%Menu_1); print "SELECTIONS=@selections\n"; The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: NOTE: "]C[" can be used as a shorthand for "]Convey[". * ]Previous[ "]Previous[" can be used in child menus. The "]Previous[" Macro contains the *Selection* of the parent menu. Unlike the "]Convey[" Macro, the "]Previous[" Macro can be used in both the "Text" element value, and the "Result" element values (when constructing method calls): The "]Previous[" Macro can also be used in the Banner. use Term::Menus; my %Menu_2=( Name => 'Menu_2', Item_1 => { Text => "]Previous[ is a ]Convey[ Utility", Convey => [ 'Good','Bad' ] }, Select => 'One', Banner => "\n Choose an Answer :" ); my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => \%Menu_2, }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my @selections=&Menu(\%Menu_1); print "SELECTIONS=@selections\n"; The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 5 >----------------------------------- Choose an Answer : 1 bash is a Good Utility 2 bash is a Bad Utility (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 1 >----------------------------------- The user sees ==> SELECTIONS = bash is a Good Utility NOTE: "]P[" can be used as a shorthand for "]Previous[". * ]Previous[{ <*Menu_Name*> } i.e. Explicit Named Macro "]Previous[{Menu_Name}" (i.e. Explicit Named Macros) can be used in child menus. The "]Previous[{Menu_Name}" Macro contains the *Selection* of any preceding menu specified with the "Menu_Name" string. The "]Previous[{Menu_Name}" follows the same conventions as the "]Previous[" Macro - but enables access to the selection of i preceding menu. This is very useful for Menu trees more than two levels deep. The "]Previous[{Menu_Name}" Macro can also be used in the Banner. use Term::Menus; my %Menu_3=( Name => 'Menu_3', Item_1 => { Text => "]Convey[ said ]P[{Menu_1} is a ]Previous[ Utility!", Convey => [ 'Bob','Mary' ] }, Select => 'One', Banner => "\n Who commented on ]Previous[{Menu_1}? :" ); my %Menu_2=( Name => 'Menu_2', Item_1 => { Text => "]Previous[ is a ]C[ Utility", Convey => [ 'Good','Bad' ], Result => \%Menu_3, }, Select => 'One', Banner => "\n Is ]P[ Good or Bad? :" ); my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => \%Menu_2, }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my @selections=&Menu(\%Menu_1); print "SELECTIONS=@selections\n"; The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk 4 /bin Utility - basename 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 5 >----------------------------------- Is bash Good or Bad? : 1 bash is a Good Utility 2 bash is a Bad Utility (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 1 >----------------------------------- Who commented on bash? : 1 Bob said bash is a Good Utility! 2 Mary said bash is a Good Utility! (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 2 >----------------------------------- The user sees ==> SELECTIONS = Mary said bash is a Good Utility! NOTE: "]P[" can be used as a shorthand for "]Previous[". "]P[{Menu_Name}" can be used as a shorthand for "]Previous[{Menu_Name}". "]C[" can be used as a shorthand for "]Convey[". * ]Selected[ "]Selected[" can only be used in a *terminal* menu. ( *A terminal menu is the last menu in the chain, or the last menu the user sees. It is the menu that defines the* "Result" *element with a method* "Result => &any_method()", *or does not have a* "Result" *element included or defined.* ) "]Selected[" is used to pass the selection of the *current* menu to the "Result" element method of the current menu: use Term::Menus; sub selected { print "\n SELECTED ITEM = $_[0]\n" } my %Menu_1=( Name => 'Menu_1', Item_1 => { Text => "/bin/Utility - ]Convey[", Convey => [ `ls -1 /bin` ], Result => "&selected(]Selected[)", # ]Selected[ macro passed to # ordinary perl subroutine. # The '&' characater is optional # but the quotes are NOT. Ordinary # subroutine calls MUST be # surrounded by either double or # single quotes. (DO NOT use # quotes around anonymous # subroutine calls, however!) }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my $selection=&Menu(\%Menu_1); print "\n SELECTION=$selection\n"; NOTE: "]S[" can be used as a shorthand for "]Selected[". NOTE: It is possible to use the same Result subroutine in different Item_ blocks, and even in other Menu blocks within the same script. Furthermore, when complex Menu structures are created using lots of anonymous subroutines with generous subroutine reuse, it can be difficult to prevent early substitution of this Macro by a parent Menu. To prevent this, use the Explicit Named Macro construct with this Macro as well - "]Selected[{Menu_Name}" Also, if the same Result subroutine is to be used by multiple nested menus, all the Menu_Names of those Menu blocks should be included in the Named section separated by the vertical bar symbol - C<]S[{Menu1_Name|Menu2_Name}> NOTE: Stepchild and Grandchild Menus - While on the topic of multiple nested menus, one of the more challenging aspects is preventing child menus from having their macros expanded or populated too "early" during runtime. Using the "Explict Name" convention ("]Selected[{Menu_Name}") helps, but there is another issue to be aware of. It is extremely useful (and powerful!) to use previous menu selections to dynamically build and return child menus for some results, but not for others. Code to reflect this goal would ordinarly look like this: $result_code = sub { my $selection=']S[{current_menu_name}'; if ($selection eq 'Return to Main Menu') { return '{main}<'; } else { my %next_menu=( Name => 'next_menu', Item_1 => { Text => ']C[', Convey => [ ... ], }, Item_2 => { ... }, ); } }; But this may not work correctly. The reason is that Term::Menus identifies menus in result blocks by explicitly looking for the 'Item_' (Item underscore) string in the block. If it finds one it will treat the result as a child menu to be I created - not a routine to be evaluated first! So, in this scenario, the routine is acting as a kind of surrogate or "step" parent, since it is not a "real" parent menu. Hence, the "stepchild" menu. In this situation it may be necessary to "trick" Term::Menus into not recognizing the embedded menu (yet) that is part of a conditional structure that will be returned, only if the conditional is true. To do that, you can code this scenario like this: $result_code = sub { my $selection=']S[{current_menu_name}'; if ($selection eq 'Return to Main Menu') { return '{main}<'; } else { my %next_menu=( # This is a "stepchild" menu Name => 'next_menu', ); my $key = 'Item'.'_1'; $next_menu{$key}={ Text => ']C[', Convey => [ ... ], }; $key = 'Item'.'_2'; $next_menu{$key}={ Text => '. . .', }; return \%next_menu; } }; While that works, it is not very elegant (and not Best Practice!). It is better in these situations to substitute the Select (C<]Select[>) or Previous (C<]Previous[>) Macros with a TEST Macro (C<]Test[> or C<]T[> is shorthand): $result_code = sub { my $selection=']T[{current_menu_name}'; # <-- Note the ]T[ if ($selection eq 'Return to Main Menu') { return '{main}<'; } else { my %next_menu=( # "stepchild" menu Name => 'next_menu', Item_1 => { Text => ']C[', Convey => [ ... ], }, Item_2 => { ... }, ); } }; The presence of the C<]Test[> macro tells Term::Menus that it's dealing with stepchild menus, and not to evaluate them early. However, there are scenario's where you want to evaluate on a condition that does not involve a child or even a step child menu - but a grandchild or great grandchild menu, etc. (This can certainly happen when there is menu re-use or recursion). In these situations Term::Menus will invariably determine there is an error condition (due to the explicitly named menu missing in the history stack) when there isn't - because there is no "obvious" way for Term::Menus to know that an explicitly named menu is not yet "supposed" to exist. In these scenarios the only option will be to suppress the error message and allow macro expansion to otherwise continue unabated. To do that, and allow processing to continue, use a "bang" (or exclamation point) character in the macro syntax after the starting bracket: C --OR-- C Hopefully, one or more of these approaches or "tricks" will deliver the results you're after. Whatever works! NOTE: if you want to return output from the Result subroutine, you must include a 'return' statement. So the sub above: sub selected { print "\n SELECTED ITEM = $_[0]\n" } Becomes: sub selected { print "\n SELECTED ITEM = $_[0]\n";return $_[0] } ANONYMOUS SUBROUTINES AND MACROS Term::Menus macros can be used *directly* in the body of anonymous subroutines! Ordinary subroutines can be used as illustrated above of course, but the macro values can only be passed as arguments to ordinary subroutines. This is much more complicated and less intuitive than using macros directly in the code itself. Below is an example of their usage. The author received a request a while back from a user, asking if it was possible to return the item number rather than it's text value. The answer of course is YES! The code below illustrates this: use Term::Menus; my @list=('One','Two','Three'); my %Menu_1=( Item_1 => { Text => "NUMBER - ]Convey[", Convey => \@list, Result => sub { my $cnt=-1;my $selection=']Selected['; foreach my $item (@list) { $cnt++; chomp($item); last if -1 'One', Banner => "\n Choose a /bin Utility :" ); my $selection=Menu(\%Menu_1); print " \nSELECTION = $selection\n"; Anonymous subroutines can be assigned directly to "Item_1" (or Item_2, etc.) elements 'Convey' and 'Result' as well as to the Menu "Banner" element. Use of the these constructs over more traditional subroutines is encouraged because it means writing less code, while enabling the code that is written to be less complex, more intuitive and readable, and certainly easier to maintain. The same anonymous routine can be use in multipe Menus or Items of a single Menu by assigning that routine to a variable, and then assigning the variable instead. NOTE: To force a return to a parent menu (assuming there is one) from a subroutine assigned to a Result element, just return '<' from the subroutine. This is extremely useful when there is a desire to process a selection, and then return to the parent menu when processing is complete. To return to any ancestor Menu in the stack, return this macro from the subroutine: "{Menu_Name}<" :-) use Term::Menus; my @list=('One','Two','Three'); my $result = sub { my $cnt=-1;my $selection=']Selected['; foreach my $item (@list) { $cnt++; chomp($item); last if -1 { Text => "NUMBER - ]Convey[", Convey => \@list, Result => $result, # Anonymous subroutine assisned via # "$result" variable }, Select => 'One', Banner => "\n Choose a /bin Utility :" ); my $selection=Menu(\%Menu_1); print " \nSELECTION = $selection\n"; RECURSIVELY CALLED MENUS There are occasions where it is desirable to re-use the same Menu template/hash configuration with dynamically discovered data. One obvious example of this is navigating directory trees. Each subsequent directory selection could potentially contain deeper levels of directories. Essentially, any data structured in any kind of relational tree layout is subject to this kind of navigation approach. Be warned however, unlike most other functionality that is handled almost entirely by the Term::Menus module, the code for doing recursive templating is mostly contained in the template/hash configuration itself. There is a "helper routine" (&get_Menu_map) that Term::Menus provides to assist with the creation of recursively-friendly configurations, but given the highly data-centric characteristics of such functionality, most of the working code must be left to the authoring and management of the user. &get_Menu_map() This is a helper routine that returns a list of ancestor menu results. This is needed when wanting to navigate a directory tree for instance. Imagine a directory path that looks like this: /one/two/three. A call to &get_Menu_map() when processing directory three with return this list: ('one','two'). The following code is an example of how to use recursion for navigating a directory tree. use Term::Menus; my %dir_menu=( Name => 'dir_menu', Item_1 => { Text => "]C[", Mark => "d", Convey => sub { if ("]P[") { my $dir="]P["; if ($^O eq 'cygwin') { $dir='/cygdrive/c/'; } else { $dir='/'; } my @xfiles=(); my @return=(); my @map=get_Menu_map; my $path=join "/", @map; opendir(DIR,"$dir$path") || die $!; @xfiles = readdir(DIR); closedir(DIR); foreach my $entry (sort @xfiles) { next if $entry eq '.'; next if $entry eq '..'; if (-1<$#map) { next unless -d "$dir$path/$entry"; } else { next unless -d "$dir/$entry"; } push @return, "$entry"; } return @return; } my @xfiles=(); my @return=(); if ($^O eq 'cygwin') { opendir(DIR,'/cygdrive/c/') || die $!; } else { opendir(DIR,'/') || die $!; } @xfiles = readdir(DIR); closedir(DIR); foreach my $entry (@xfiles) { next if $entry eq '.'; next if $entry eq '..'; next unless -d "$entry"; push @return, "$entry"; } return @return; }, Result => { 'dir_menu'=>'recurse' }, }, Item_2 => { Text => "]C[", Select => 'Many', Convey => sub { if ("]P[") { my $dir="]P["; if ($^O eq 'cygwin') { $dir='/cygdrive/c/'; } else { $dir='/'; } my @xfiles=(); my @return=(); my @map=get_Menu_map; my $path=join "/", @map; opendir(DIR,"$dir/$path") || die $!; @xfiles = readdir(DIR); closedir(DIR); foreach my $entry (sort @xfiles) { next if $entry eq '.'; next if $entry eq '..'; if (-1<$#map) { next if -d "$dir/$path/$entry"; } else { next if -d "$dir/$entry"; } push @return, "$entry"; } return @return; } my @xfiles=(); my @return=(); if ($^O eq 'cygwin') { opendir(DIR,'/cygdrive/c/') || die $!; } else { opendir(DIR,'/') || die $!; } @xfiles = readdir(DIR); closedir(DIR); foreach my $entry (@xfiles) { next if $entry eq '.'; next if $entry eq '..'; next if -d "$entry"; push @return, "$entry"; } return @return; }, }, Banner => " Current Directory: ]P[\n", ); my $selection=Menu(\%dir_menu); if (ref $selection eq 'ARRAY') { print "\nSELECTION=",(join " ",@{$selection}),"\n"; } else { print "\nSELECTION=$selection\n"; } USAGE and NAVIGATION Usage of "&pick()" and/or "&Menu()" during the runtime of a script in which one or both are included, is simple and intuitive. Nearly everything the end user needs in terms of instruction is included on-screen. The script-writer/developer/programmer can also include whatever instructions s/he deems necessary and/or helpful in the customizable "Banner" (as described above). There is however, one important feature about using "&Menu()" with sub-menus that's important to know about. Forward ' > ' and Backward ' < ' Navigation When working with more than one "&Menu()" screen, it's valuable to know how to navigate back and forth between the different "&Menu()" levels/layers. For example, above was illustrated the output for two layers of menus - a parent and a child: The user sees ==> Choose a /bin Utility : 1. /bin Utility - arch 2. /bin Utility - ash 3. /bin Utility - awk 4. /bin Utility - basename 5. /bin Utility - bash 6. /bin Utility - cat 7. /bin Utility - chgrp 8. /bin Utility - chmod 9. /bin Utility - chown 10. /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< 5 >----------------------------------- The user sees ==> Choose an Answer : 1 bash is a Good Utility 2 bash is a Bad Utility (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: In the above example, suppose that the user "fat-fingered" his/her choice, and really didn't want to "bash" bash, but wanted to bash awk instead. Is restarting the whole script/application now necessary? Suppose it was a process that had run overnight, and the user is seeing this menu through fogged glasses from the steam rising out of their morning coffee? Having to run the whole job again would not be welcome news for the BOSS. THANKFULLY, navigation makes this situation avoidable. All the user would have to do is type ' < ' to go backward to the previous menu, and ' > ' to go forward to the next menu (assuming there is one in each case): The user sees ==> Choose an Answer : 1 bash is a Good Utility 2 bash is a Bad Utility (Press [F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: --< > >------------------------------ The user sees ==> Choose a /bin Utility : 1 /bin Utility - arch 2 /bin Utility - ash 3 /bin Utility - awk 4 /bin Utility - basename - 5 /bin Utility - bash 6 /bin Utility - cat 7 /bin Utility - chgrp 8 /bin Utility - chmod 9 /bin Utility - chown 10 /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: Note in the above example the Dash ' - ' in front of item 5. This informs the user that s/he had previously selected this item. To clear the selection, the user would simply choose item 5 again. This effectively deletes the previous choice and restores the menu for a new selection. If the user was satisfied with the choice, and was simply double checking thier selection, they simply repeat the navigation process by typing ' > ' - then - and returning to the child menu they left. If the child menu was a *multiple-selection* menu, and the user had made some selections before navigating back to the parent menu, the user would see a ' + ' rather than a ' - '. This informs the user that selections were made in the child menu. Choose a /bin Utility : 1. /bin Utility - arch 2. /bin Utility - ash 3. /bin Utility - awk 4. /bin Utility - basename + 5. /bin Utility - bash 6. /bin Utility - cat 7. /bin Utility - chgrp 8. /bin Utility - chmod 9. /bin Utility - chown 10. /bin Utility - cp a. Select All c. Clear All f. FINISH ___ 93 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: View Sorted Items ' % ' When working with numerous items in a single menu, it may be desirable to see the set of choices organized in either descending or reverse acscii order. Term::Menus provides this feature with the *Percent* ' % ' key. Simply type ' % ' and the items will be sorted in descending ascii order. Type ' % ' again, and you will see the items reverse sorted. Assume that we have the following menus. The user sees ==> Choose a /bin Utility : * 1 [.exe * 2 2to3 3 2to3-3.2 * 4 411toppm.exe 5 a2p.exe 6 aaflip.exe 7 aclocal * 8 aclocal-1.10 9 aclocal-1.11 * 10 aclocal-1.12 a. Select All c. Clear All f. FINISH ___ 1925 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< % >----------------------------------- The user sees ==> Choose a /bin Utility : * 2. 2to3 3. 2to3-3.2 * 4. 411toppm.exe 759. FvwmCommand.exe 1650. Ted.exe 1782. WPrefs.exe 1785. X 1889. XWin.exe 1808. Xdmx.exe 1815. Xephyr.exe a. Select All c. Clear All f. FINISH (Type '<' to return to previous Menu) ___ 1925 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: And if we choose to enter ' % ' *again* --< % >----------------------------------- The user sees ==> Choose a /bin Utility : 1925 znew 1924 zmore 1923 zless 1922 zipsplit.exe 1921 zipnote.exe 1920 zipinfo.exe 1919 zipgrep 1918 zipcloak.exe 1917 zip.exe 1916 zgrep a. Select All c. Clear All f. FINISH (Type '<' to return to previous Menu) ___ 1925 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: This submenu of sorted selections works just like any other menu. The user can deselect an item, clear all items, re-choose all items, etc. The choices made here are preserved when the user navigates back to the original (parent) menu. In other words, if Item 1. is deselected in the sorted menu, Item 1. will also be deselected in the parent menu. Navigating back to the parent is necessary - the menu will not generate results from a sort menu. Use either the LEFTARROW ' < ' key or FINISH key ' F or f ' to return to the parent menu, and then continue your menu activities there. View Summary of Selected Items ' * ' When working with numerous items in a single menu, it is desirable to see the set of choices made before leaving the menu and committing to a non-returnable forward (perhaps even critical) process. Term::Menus provides this feature with the *Star* ' * ' key. Assume we have the following menu with 93 Total Choices. Assume further that we have selected items 1,3,9 & 11. Note that we cannot see Item 11 on the first screen since this menu is configured to show only 10 Items at a time. The user sees ==> Choose a /bin Utility : * 1 [.exe 2 2to3 * 3 2to3-3.2 4 411toppm.exe 5 a2p.exe 6 aaflip.exe 7 aclocal 8 aclocal-1.10 * 9 aclocal-1.11 10 aclocal-1.12 a. Select All c. Clear All f. FINISH ___ 1925 Total Choices |_v_| Scroll with ARROW keys [F1] for HELP ([ESC] to Quit) PLEASE ENTER A CHOICE: --< * >----------------------------------- The user sees ==> Choose a /bin Utility : * 1 [.exe * 3 2to3-3.2 * 9 aclocal-1.11 * 11 aclocal-1.13 a. Select All c. Clear All f. FINISH (Type '<' to return to previous Menu) ([F1] for HELP) ([ESC] to Quit) PLEASE ENTER A CHOICE: This submenu of summary selections works just like any other menu. The user can deselect an item, clear all items, re-choose all items, etc. The choices made here are preserved when the user navigates back to the original (parent) menu. In other words, if Item 1. is deselected in the summary menu, Item 1. will also be deselected in the parent menu. Navigating back to the parent is necessary - the menu will not generate results from a summary menu. Use either the LEFTARROW ' < ' key or FINISH key ' F or f ' to return to the parent menu, and then continue your menu activities there. AUTHOR Brian M. Kelly COPYRIGHT Copyright (C) 2000-2015 by Brian M. Kelly. This program is free software; you can redistribute it and/or modify it under the terms of the GNU Affero General Public License. (http://www.gnu.org/licenses/agpl.html).