VkPrefItem(3x)VkPrefItem(3x)NAMEVkPrefItem - Abstract class that supports preference items
INHERITS FROM
VkComponent : VkCallbackObject
HEADER FILE
#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 DESCRIPTIONVkPrefItem 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 DESCRIPTIONSVkPrefItem()
virtual void ~VkPrefItem(void);
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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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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
Inherited from VkComponent
installDestroyHandler(), removeDestroyHandler(), widgetDestroyed(),
setDefaultResources(), getResources(), manage(), unmanage(),
baseWidget(), okToQuit(), _name, _baseWidget, _w, deleteCallback
Inherited from VkCallbackObject
callCallbacks(), addCallback(), removeCallback(),
removeAllCallbacks(),
KNOWN DERIVED CLASSES
VkPrefGroup, VkPrefList, VkPrefRadio, VkPrefText, VkPrefToggle,
VkPrefOption, VkPrefCustom, VkPrefEmpty, VkPrefLabel, VkPrefSeparator,
KNOWN CLASSES THAT USE THIS CLASS
VkPrefDialog, VkPrefGroup, VkPrefList, VkPrefRadio,
SEE ALSO
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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