usual(3itk) [debian man page]

usual(3itk)							     [incr Tk]							       usual(3itk)

NAME

       usual - access default option-handling commands
	    for a mega-widget component

SYNOPSIS

       usual ?tag? ?commands?

DESCRIPTION

       The  usual  command  is	used outside of an [incr Tcl] class definition to define the usual set of option-handling commands for a component
       widget.	Option-handling commands are used when a component is registered with the Archetype base class via the "itk_component add" method.
       They  specify  how  the component's configuration options should be integrated into the composite option list for the mega-widget.  Options
       can be kept, renamed, or ignored, as described in the Archetype man page.

       It is tedious to include the same declarations again and again whenever components are added.  The usual command  allows  a  standard  code
       fragment to be registered for each widget class, which is used by default to handle the options.  All of the standard Tk widgets have usual
       declarations defined in the [incr Tk] library.  Similar usual declarations should be created whenever a new mega-widget class is conceived.
       Only the most-generic options should be included in the usual declaration.

       The  tag  name  is  usually the name of a widget class, which starts with a capital letter; however, any string registered here can be used
       later with the usual command described on the Archetype man page.

       If the commands argument is specified, it is associated with the tag string, and can be accessed later via itk_component add.

       If only the tag argument is specified, this command looks for an existing tag name and returns the commands associated with it.	 If  there
       are no commands associated with tag, this command returns the null string.

       If no arguments are specified, this command returns a list of all tag names previously registered.

EXAMPLE

       Following is the usual declaration for the standard Tk button widget: itk::usual Button {
	   keep -background -cursor -foreground -font
	   keep -activebackground -activeforeground -disabledforeground
	   keep -highlightcolor -highlightthickness
	   rename  -highlightbackground -background background Background } Only the options that would be common to all buttons in a single mega-
       widget are kept or renamed.  Options like "-text" that would be unique to a particular button are ignored.

KEYWORDS

       itk, Archetype, component, mega-widget

itk									3.0							       usual(3itk)

itk(3itk)							     [incr Tk]								 itk(3itk)

NAME

       itk - framework for building mega-widgets in Tcl/Tk

DESCRIPTION

       Mega-widgets are high-level widgets that are constructed using Tk widgets as component parts, usually without any C code.  A fileselection-
       box, for example, may have a few listboxes, some entry widgets and some control buttons.  These individual widgets are put  together  in  a
       way  that  makes  them  act  like one big widget.  A fileselectionbox mega-widget can be created with a command like: fileselectionbox .fsb
       -background blue -foreground white Once it has been created, it can be reconfigured with a command like: .fsb configure	-background  green
       -foreground  black and all of its internal components will change color.  Each mega-widget has a set of methods that can be used to manipu-
       late it.  For example, the current selection can be queried from a fileselectionbox like this: set fileName [.fsb get] In effect,  a  mega-
       widget looks and acts exactly like a Tk widget, but is considerably easier to implement.

       [incr Tk] is a framework for building mega-widgets.  It uses [incr Tcl] to support the object paradigm, and adds base classes which provide
       default widget behaviors.

       All [incr Tk] widgets are derived from the Archetype base class.  This class manages internal component widgets, and provides methods  like
       "configure" and "cget" to access configuration options.

       The Widget base class inherits everything from Archetype, and adds a Tk frame which acts as a container for the mega-widget.  It is used to
       build mega-widgets that sit inside of other frames and toplevels.  Derived classes create other internal components and pack them into  the
       "hull" frame created by the Widget base class.

       The  Toplevel  base  class inherits everything from Archetype, but adds a Tk toplevel which acts as a container for the mega-widget.  It is
       used to build mega-widgets, such as dialog boxes, that have their own toplevel window.  Derived classes create  other  internal	components
       and pack them into the "hull" toplevel created by the Toplevel base class.

[incr Widgets] LIBRARY
       [incr Widgets]  is  a  mega-widget library built using [incr Tk].  It can be used right out of the box, and contains more than 30 different
       widget classes, including:

       -      fileselectiondialog

       -      tabnotebook

       -      panedwindow

       -      combobox

       -      optionmenu

       -      scrolledlistbox

       -      scrolledframe

       -      messagedialog

       -      and many others...

       The catalog demo in the "iwidgets/demos" directory shows all of the available widgets in action.  Each widget class has its  own  man  page
       describing the features available.

KEYWORDS

       class, object, object-oriented, mega-widget

itk									3.0								 itk(3itk)