Widget(n)							     [incr Tk]								 Widget(n)

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NAME

       Widget - base class for mega-widgets within a frame

INHERITANCE

       itk::Archetype <- itk::Widget

STANDARD OPTIONS

       background      cursor

       See the "options" manual entry for details on the standard options.
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DESCRIPTION

       The Widget class inherits everything from the Archetype class, and adds a Tk frame called the "hull" component to represent the body of the
       mega-widget.  The window class name for the hull is set to the most-specific class  name  for  the  mega-widget.   The  protected  variable
       itk_interior contains the window path name for the "hull" component.  Derived classes specialize this widget by packing other widget compo-
       nents into the hull.

       Since the hull for the Widget class is implemented with a Tk frame, mega-widgets in the Widget class can be packed into	other  frames  and
       toplevels.

COMPONENTS

       Name:	       hull
       Class:	       Frame

	      The  "hull"  component acts as the body for the entire mega-widget.  Other components are packed into the hull to further specialize
	      the widget.

EXAMPLE

       The following example implements a simple TextDisplay mega-widget.  It creates a read-only display of text with a text widget and a scroll-
       bar.
	      option add *TextDisplay.wrap none widgetDefault
	      option add *TextDisplay.textBackground ivory widgetDefault
	      option add *TextDisplay.width 40 widgetDefault
	      option add *TextDisplay.height 10 widgetDefault

	      itcl::class TextDisplay {
		  inherit itk::Widget

		  constructor {args} {
		      itk_component add text {
			  text $itk_interior.info -state disabled		  -yscrollcommand [code $itk_interior.sbar set]
		      } {
			  usual
			  keep -tabs -wrap -width -height
			  rename -background -textbackground textBackground Background
		      }
		      pack $itk_component(text) -side left -expand yes -fill both

		      itk_component add scrollbar {
			  scrollbar $itk_interior.sbar		       -command [code $itk_interior.info yview]
		      }
		      pack $itk_component(scrollbar) -side right -fill y

		      eval itk_initialize $args
		  }

		  public method display {info}
		  public method append {info}
	      }

	      itcl::body TextDisplay::display {info} {
		  $itk_component(text) configure -state normal
		  $itk_component(text) delete 1.0 end
		  $itk_component(text) insert 1.0 $info
		  $itk_component(text) configure -state disabled
	      }

	      itcl::body TextDisplay::append {info} {
		  $itk_component(text) configure -state normal
		  $itk_component(text) insert end $info
		  $itk_component(text) configure -state disabled
	      }

	      itk::usual TextDisplay {
		  keep -background -cursor -foreground -font
		  keep -activebackground -activerelief
		  keep -highlightcolor -highlightthickness
		  keep -insertbackground -insertborderwidth -insertwidth
		  keep -insertontime -insertofftime
		  keep -selectbackground -selectborderwidth -selectforeground
		  keep -textbackground -troughcolor
	      }

	      #
	      # EXAMPLE:  Display the /etc/passwd file
	      #
	      TextDisplay .file -background red
	      pack .file

	      .file display [exec cat /etc/passwd]

KEYWORDS

       itk, Archetype, Widget, mega-widget

itk									3.0								 Widget(n)