Menu: Conveniently manipulate menus, whatever the window

Description

These functions provide an unifying way of dealing with menus in R. It is ispired from the winMenuXXX() functions under Windows that allow easy manipulation of custom menus in Rgui.exe. Currently, they support all the functionnalities of winMenuXXX() functions and they bring a convenient similar layer on top of Tk menus to manipulate them in a similar way.

Usage

MenuAdd(menu, ...)
  MenuAddItem(menu, item, action, image = "", accel = "", options = "")
  MenuDel(menu)
  MenuDelItem(menu, item)
  MenuNames()
  MenuItems(menu)
  MenuType(menu, warn = TRUE)
  MenuInvoke(menu, item)
  MenuChangeItem(menu, item, action = "", options = "")
  MenuStateItem(menu, item, active = TRUE)
  MenuRead(file = "Menus.txt")
  MenuReadPackage(package, subdir = "gui", file = "Menus.txt")

  ## S3 method for class 'guiMenu':
print(x, \dots)

Arguments

Name of a menu

item

Name of a menu item

action

Action the menu triggers (R code)

image

Name of an image to display at left of the menu item

accel

Accelerator (keystroke) to use to trigger this menu item

options

Additional options, for instance "disable" to disable the menu at creation.

warn

Do we issue a warning if the type of menu is not recognized?

active

Do we enable or disable the menu item?

file

A file containing menu specifications to read

package

Name of a package from where to load menu specifications

subdir

Subdirectory in the package where the menu specifications are stored. By default, it is the "gui" subdirectory.

An object of class 'guiMenu'

...

Further arguments passed to the function

Value

MenuAdd() and MenuAddItem() return the handle to the newly created menu/menu item invisibly. MenuDel() and MenuDelItem() return invisibly TRUE if the resource is found and deleted, FALSE otherwise. MenuNames() returns the list of all menus registered in .guiMenus in the 'TempEnv' environment. MenuInvoke() returns invisibly TRUE if the menu item was invoked, FALSE otherwise. MenuRead() and MenuReadPackage() return invisibly the list of menus that are imported and created.

Details

These functions care about creating, deleting and managing custom menus. Informations and handles to the various menus created with these functions are stored in the .guiMenus variable, located in the 'TempEnv' environment.

Examples

Run this code

## These cannot be run by examples() but should be OK when pasted
## into an interactive R session with the tcltk package loaded
## Run these commands one at a time and look at menus...


## Under RGui and Windows only! ##
# Create menus in Rgui, using a specification file
MenuReadPackage("svWidgets")
MenuNames()
(MenuItems("$ConsoleMain/Testit"))

# Create menus manually in Rgui
MenuAdd("$ConsoleMain/Testit2")
MenuAddItem("$ConsoleMain/Testit2", "Trial", "ls()")
MenuNames()
(MenuItems("$ConsoleMain/Testit2"))
MenuStateItem("$ConsoleMain/Testit2", "Trial", FALSE)
MenuStateItem("$ConsoleMain/Testit2", "Trial", TRUE)
# Buggy? -> MenuChangeItem("$ConsoleMain/Testit2", "Trial", "search()")
(MenuItems("$ConsoleMain/Testit2"))


## Under any system supporting Tcl/Tk ##
# Create and manipulate Tk menus
WinAdd("tt", title = "A Tk window with menus", pos ="-40+20")
MenuAdd("$Tk.tt/Misc")
MenuNames()
(MenuItems("$Tk.tt/Misc"))   # Still nothing in it
MenuAddItem("$Tk.tt/Misc", "List &variables", "print(ls(envir = .GlobalEnv))")
MenuAddItem("$Tk.tt/Misc", "Say &yo!", "cat('yo!\n')")

MenuDelItem("$Tk.tt/Misc", "Say &yo!")
MenuAddItem("$Tk.tt/Misc", "-")
MenuAddItem("$Tk.tt/Misc", "&Say yo! twice", "cat('yo! yo!\n')")
(MenuItems("$Tk.tt/Misc"))

ImgReadPackage("svWidgets")	# Make sure images are loaded
MenuAdd("$Tk.tt/Misc/Sub&Menu")
MenuAddItem("$Tk.tt/Misc/Sub&Menu", "T&rial", "cat('Trial trigerred!\n')")
MenuAddItem("$Tk.tt/Misc", "Tria&l2", "cat('Trial with image and accel!\n')",
	image = "$Tk.butOpen", accel = "Ctrl+T")
MenuNames()
(MenuItems("$Tk.tt/Misc"))
MenuStateItem("$Tk.tt/Misc", "Tria&l2", FALSE)
MenuStateItem("$Tk.tt/Misc", "Tria&l2", TRUE)
MenuStateItem("$Tk.tt/Misc", "Sub&Menu", FALSE)
MenuStateItem("$Tk.tt/Misc", "Sub&Menu", TRUE)
MenuChangeItem("$Tk.tt/Misc", "Tria&l2", options = "underline = 1")
# This is the way to change binding
tkbind(WinGet("tt"), "<Control-r>", function() MenuInvoke("$Tk.tt/Misc", "Tria&l2"))
MenuChangeItem("$Tk.tt/Misc", "Tria&l2", action = 'cat("new action for Tria&l2!\n")')
MenuInvoke("$Tk.tt/Misc", "Tria&l2")
(MenuItems("$Tk.tt/Misc"))
MenuDelItem("$Tk.tt/Misc", "Tria&l2")
MenuDel("$Tk.tt/Misc")
MenuNames()
# The following command generates an error!
(MenuItems("$Tk.tt/Misc"))
WinDel("tt")