VkPrefItem(3x)							VkPrefItem(3x)

NAME    [Toc]    [Back]

     VkPrefItem	- Abstract class that supports preference items

INHERITS FROM    [Toc]    [Back]

     VkComponent : VkCallbackObject

HEADER FILE    [Toc]    [Back]

     #include <Vk/VkPrefItem.h>

PUBLIC PROTOCOL	SUMMARY
   Access Functions
	   virtual int type(void);
	   virtual Boolean changed(void);
	   virtual Dimension labelHeight(void);
	   virtual Dimension baseHeight(void);
	   virtual void	setLabelHeight(Dimension height);
	   virtual void	setBaseHeight(Dimension	height);
	   Widget labelWidget(void);


   Activating/Deactivating
	   virtual void	activate();
	   virtual void	deactivate();

CLASS DESCRIPTION    [Toc]    [Back]

	  VkPrefItem is	an abstract class that supports	easy-to-create
	  preference panels. The classes derived from VkPrefItem form a	simple
	  toolkit that creates preference panels, typically placed in a
	  dialog.  When	creating a preference pane using the VkPref classes
	  one does not normally	pay much attention to layout, but allows the
	  VkPref classes to create a layout automatically. The VkPref classes
	  provide users	the ability to cancel any operation at any time,
	  reverting all	preferences to their previous values. Automatically.
	  Programmers who use the preference classes do	not have to deal with
	  callbacks or data retrieval on a per-widget basis, but instead allow
	  the VkPref classes to	handle all intermediate	states transparently.
	  Applications simply look at the final	values of all preferences to
	  see what has changed when the	user applies the preferences.

	  Preference panels are	organized around from the VkPrefDialog class,
	  the VkPrefList class,	and the	VkPrefGroup class. See man pages for
	  those	classes	for examples of	how to create preference panels.

FUNCTION DESCRIPTIONS    [Toc]    [Back]

   VkPrefItem()
	   virtual void	~VkPrefItem(void);






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VkPrefItem(3x)							VkPrefItem(3x)



	  The VkPrefItem destructor destroys the companion label widget, and
	  frees	strings	created	for the	base and label widget names.

   type()
	   virtual int type(void);


	  The type method is overridden	by subclasses to return	the true
	  preference item type:	PI_group, PI_list, PI_radio, PI_text,
	  PI_toggle, PI_option,	PI_custom, PI_empty, PI_label, or
	  PI_separator.	 These correspond to the subclasses VkPrefGroup,
	  VkPrefList, VkPrefRadio, VkPrefText, VkPrefToggle, VkPrefOption,
	  VkPrefCustom,	VkPrefEmpty, VkPrefLabel, and VkPrefSeparator,
	  respectively.

   activate()
	   void	activate();
	   void	deactivate();


	  Activate and deactivate will sensitize and desensitize,
	  respectively,	the preference object.	The default state is
	  sensitive.

   changed()
	   virtual Boolean changed(void);


	  This method indicates	whether	the current value differs from the
	  real value.  Applications may	want to	call this method for
	  preference objects when to test whether the user has actually
	  changed the value.  Typically, a VkPrefDialog	is used	and
	  applications use this	method in the apply callback.

   isContainer()
	   virtual Boolean isContainer(void);


	  Indicates whether this object	contains other preference objects
	  (e.g.	VkPrefList, VkPrefGroup).

   labelHeight()
	   virtual Dimension labelHeight(void);
	   virtual void	setLabelHeight(Dimension height);


	  The labelHeight method returns the height, in	pixels,	of the label
	  widget.  The setLabelHeight method changes the height.

   baseHeight()





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VkPrefItem(3x)							VkPrefItem(3x)



	   virtual Dimension baseHeight(void);
	   virtual void	setBaseHeight(Dimension	height);


	  The baseHeight method	returns	the height, in pixels, of the base
	  widget.  The setBaseHeight method changes the	height.

   labelWidget()
	   Widget labelWidget(void);


	  Returns the label widget for the preference object.  If there	is no
	  label	widget,	NULL is	returned.

INHERITED MEMBER FUNCTIONS    [Toc]    [Back]

   Inherited from VkComponent
	  installDestroyHandler(), removeDestroyHandler(), widgetDestroyed(),
	  setDefaultResources(), getResources(), manage(), unmanage(),
	  baseWidget(),	okToQuit(), _name, _baseWidget,	_w, deleteCallback


   Inherited from VkCallbackObject    [Toc]    [Back]
	  callCallbacks(), addCallback(), removeCallback(),
	  removeAllCallbacks(),

KNOWN DERIVED CLASSES    [Toc]    [Back]

     VkPrefGroup, VkPrefList, VkPrefRadio, VkPrefText, VkPrefToggle,
     VkPrefOption, VkPrefCustom, VkPrefEmpty, VkPrefLabel, VkPrefSeparator,

KNOWN CLASSES THAT USE THIS CLASS    [Toc]    [Back]

     VkPrefDialog, VkPrefGroup,	VkPrefList, VkPrefRadio,

SEE ALSO    [Toc]    [Back]

     VkComponent, VkPrefDialog,	VkPrefGroup, VkPrefList, VkPrefRadio
     ViewKit Programmer's Guide
     The X Window System, DEC Press, Bob Sheifler and Jim Gettys
     The X Window System Toolkit, DEC Press, Paul Asente and Ralph Swick
     The OSF/Motif Programmers Reference, Prentice Hall, OSF


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