NAME

XwPanelWidgetClass − An X Widget for creating panels. 

SYNOPSIS

#include <X11/StringDefs.h>
#include <X11/Intrinsic.h>
#include <Xw/Xw.h>
#include <Xw/Panel.h>

CLASSES

A subclass of Core, Composite, Constraint and XwManagerClass. 

The widget class to use when creating a Panel widget is XwpanelWidgetClass. 

The class name of Panel is Panel. 

DESCRIPTION

Panel provides a simple creation mechanism for the creation of application windows and associated menus.  The panel widget is also appropriate for application sub-windows. 

Panel will manage three types of children.  Panel may have at most one child of each type.  The types are titlebar, menu, and work space.  Children are associated with these types via constraint resources (see below).  Panel ignores all extra or unknown children. 

Panel lays out its children such that the child of type titlebar is on the top, the child of type menu is below, and the child of type work space is on the bottom.  Display of the titlebar child can be optionally inhibitted if the panel is under the control of a window manager which provides titlebars. 

When Panel has its width changed by its parent, the menu, if displayed, is allowed to pick its own height, the title remains the same height and the work space is diminished or enlarged to fill the remaining available space.  When Panel has its height reduced by its parent, space is taken from the work space until the work space is completely hidden.  Further reductions in the height of Panel are shared between the title and the menu.  When Panel has its height increased by its parent, if either the title or the menu are less than their optimum height, they are given the space until they reach their optimum height for the given width.  If both the title and the menu are at their optimum height all space is given to the work space. 

The initial width of Panel is the widest of all its children (padding is taken into account).  The initial height of Panel is the sum of the heights of all its children and their padding. 

When an application is running in a Panel with a titling window manager, there is a possibility of double titling.  Unfortunately, the application writer cannot know at the time of development whether or not the user will have a titling window manager.  Panel has two resources which together allow runtime decisions about titling.  The first, XtNtopLevel, indicates whether the Panel is a canidate for double titling.  The application must always set this variable appropriately.  The second resource, XtNdisplayTitle, indicates whether or not the Panel should display a title. 
 

NEW RESOURCES

To specify any of these resources within a resource defaults file, simply drop the XtN prefix from the resource name.  Panel defines the following new resources:  

XtNtopLevel
Indicates whether not the panel is a candidate for management by a window manager.  This should always be set by the application.

XtNdisplayTitle
Ignored if XtNtopLevel is FALSE.

Otherwise, if XtNdisplayTitle is TRUE, the titlebar child will be displayed.  If XtNdisplayTitle is FALSE, the titlebar child will not be displayed. 

This resource should be set by the user in the resource defaults file.  If the user runs the application without a window manager or with a non-titling window manager, this resource should be set to TRUE.  If the user runs with a titling window manager this resource should be set to FALSE. 

XtNvSpace
Padding between the top of the Panel and the top child in pixels, and between the bottom of the Panel and the bottom child in pixels.

XtNhSpace
Padding between the sides of the Panel and the sides of the displayed children.

XtNtitleToMenuPad
If both a title and a menu child are being displayed, the padding between them in pixels.

XtNworkSpaceToSiblingPad
The padding between the work space child and the sibling above it. If there is no title nor menu being displayed this resource is ignored.

CONSTRAINT RESOURCES

The following resources will be attached to every widget inserted into Panel.  Refer to CONSTRAINT(3X) for a general discussion of constraint resources.   

XtNwidgetType
Indicates to Panel what type of child it is.  The possible values are, XwWORK_SPACE, specified in a resource defaults file as "work space", XwTITLE, specified in a resource defaults file as "title", and XwPULLDOWN, specified in a resource defaults file as "pulldown".

XtNcausesResize
Controls whether changes in the child geometry can cause the Panel to make a geometry request of its parent.  If TRUE for only one child, Panel will request changes whenever that child requests changes.  If TRUE for multiple children, Panel will request changes whenever any of that set of children grow, and when all of that set of children have shrunk.

The behavior of this resource can be nullified by setting XwNLayout to XwIGNORE. 

INHERITED RESOURCES

The following resources are inherited from the named superclasses:  

TRANSLATIONS

The default translation set defining is as follows:

<EnterWindow>:          enter()
<LeaveWindow>:          leave()

ACTIONS

enter:  If keyboard traversal is active (argument type XtNtraversalOn with argument value TRUE), initiate keyboard traversal.  leave:  If keyboard traversal is active (argument type XtNtraversalOn with argument value TRUE), terminate keyboard traversal. 

ORIGIN

Hewlett-Packard Company. 

SEE ALSO

CORE(3X), CONSTRAINT(3X), XWMANAGER(3X)

September 29, 2021