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XmCascadeButton

NAME

XmCascadeButton - The CascadeButton widget class

SYNOPSIS

#include <Xm/CascadeB.h>

DESCRIPTION

CascadeButton links two MenuPanes or a MenuBar to a MenuPane.

It is used in menu systems and must have a RowColumn parent with its XmNrowColumnType resource set to XmMENU_BAR, XmMENU_POPUP or XmMENU_PULLDOWN.

It is the only widget that can have a Pulldown MenuPane attached to it as a submenu. The submenu is displayed when this widget is activated within a MenuBar, a PopupMenu, or a PulldownMenu. Its visuals can include a label or pixmap and a cascading indicator when it is in a Popup or Pulldown MenuPane; or, it can include only a label or a pixmap when it is in a MenuBar.

The default behavior associated with a CascadeButton depends on the type of menu system in which it resides. By default, BSelect controls the behavior of the CascadeButton. In addition, BMenu controls the behavior of the CascadeButton if it resides in a PopupMenu system. The actual mouse button used is determined by its RowColumn parent.

A CascadeButton's visuals differ from most other button gadgets. When the button becomes armed, its visuals change from a 2-D to a 3-D look, and it displays the submenu that has been attached to it. If no submenu is attached, it simply changes its visuals.

When a CascadeButton within a Pulldown or Popup MenuPane is armed as the result of the user moving the mouse pointer into the widget, it does not immediately display its submenu. Instead, it waits a short amount of time to see if the arming was temporary (that is, the user was simply passing through the widget), or whether the user really wanted the submenu posted. This time delay is configurable via XmNmappingDelay.

CascadeButton provides a single mechanism for activating the widget from the keyboard. This mechanism is referred to as a keyboard mnemonic. If a mnemonic has been specified for the widget, the user may activate the CascadeButton by simply typing the mnemonic while the CascadeButton is visible. If the CascadeButton is in a MenuBar and the MenuBar does not have the focus, the MAlt modifier must be pressed with the mnemonic. Mnemonics are typically used to interact with a menu via the keyboard interface.

If in a Pulldown or Popup MenuPane and there is a submenu attached, the XmNmarginBottom, XmNmarginLeft, XmNmarginRight, and XmNmarginTop resources may enlarge to accommodate XmNcascadePixmap. XmNmarginWidth defaults to 6 if this resource is in a MenuBar; otherwise, it takes Label's default, which is 2.

Classes

CascadeButton inherits behavior and resources from Core, XmPrimitive, and XmLabel classes.

The class pointer is xmCascadeButtonWidgetClass.

The class name is XmCascadeButton.

New Resources

The following table defines a set of widget resources used by the programmer to specify data. The programmer can also set the resource values for the inherited classes to set attributes for this widget. To reference a resource by name or by class in a .Xdefaults file, remove the XmN or XmC prefix and use the remaining letters. To specify one of the defined values for a resource in a .Xdefaults file, remove the Xm prefix and use the remaining letters (in either lowercase or uppercase, but include any underscores between words). The codes in the access column indicate if the given resource can be set at creation time (C), set by using XtSetValues (S), retrieved by using XtGetValues (G), or is not applicable (N/A). 


XmCascadeButton Resource Set

Name                  Class            Type            Default  Access

XmNactivateCallback   XmCCallback      XtCallbackList  NULL     C

XmNcascadePixmap      XmCPixmap        Pixmap          dynamic  CSG

XmNcascadingCallback  XmCCallback      XtCallbackList  NULL     C

XmNmappingDelay       XmCMappingDelay  int             180 ms   CSG

XmNsubMenuId          XmCMenuWidget    Widget          NULL     CSG
XmNactivateCallback
Specifies the list of callbacks that is called when the user activates the CascadeButton widget, and there is no submenu attached to pop up. The activation occurs by releasing a mouse button or by typing the mnemonic associated with the widget. The specific mouse button depends on information in the RowColumn parent. The reason sent by the callback is XmCR_ACTIVATE.
XmNcascadePixmap
Specifies the cascade pixmap displayed on one end of the widget when a CascadeButton is used within a Popup or Pulldown MenuPane and a submenu is attached. The Label class resources XmNmarginBottom, XmNmarginLeft, XmNmarginRight, and XmNmarginTop may be modified to ensure that room is left for the cascade pixmap. The default cascade pixmap is an arrow pointing to the side of the menu where the submenu will appear.
XmNcascadingCallback
Specifies the list of callbacks that is called just prior to the mapping of the submenu associated with CascadeButton. The reason sent by the callback is XmCR_CASCADING.
XmNmappingDelay
Specifies the amount of time, in milliseconds, between when a CascadeButton becomes armed and when it maps its submenu. This delay is used only when the widget is within a Popup or Pulldown MenuPane. The value must not be negative.
XmNsubMenuId
Specifies the widget ID for the Pulldown MenuPane to be associated with this CascadeButton. The specified MenuPane is displayed when the CascadeButton becomes armed. The MenuPane must have been created with the appropriate parentage depending on the type of menu used. See XmCreateMenuBar(3X), XmCreatePulldownMenu(3X), and XmCreatePopupMenu(3X) for more information on the menu systems.

Inherited Resources

CascadeButton inherits behavior and resources from the following superclasses. For a complete description of each resource, refer to the man page for that superclass. 


XmLabel Resource Set

Name                       Class                      Type               Default                 Access

XmNaccelerator             XmCAccelerator             String             NULL                    N/A

XmNacceleratorText         XmCAcceleratorText         XmString           NULL                    N/A

XmNalignment               XmCAlignment               unsigned char      dynamic                 CSG

XmNfontList                XmCFontList                XmFontList         dynamic                 CSG

XmNlabelInsensitivePixmap  XmCLabelInsensitivePixmap  Pixmap             XmUNSPECIFIED_PIXMAP    CSG

XmNlabelPixmap             XmCLabelPixmap             Pixmap             XmUNSPECIFIED_PIXMAP    CSG

XmNlabelString             XmCXmString                XmString           dynamic                 CSG

XmNlabelType               XmCLabelType               unsigned char      XmSTRING                CSG

XmNmarginBottom            XmCMarginBottom            Dimension          dynamic                 CSG

XmNmarginHeight            XmCMarginHeight            Dimension          2                       CSG

XmNmarginLeft              XmCMarginLeft              Dimension          0                       CSG

XmNmarginRight             XmCMarginRight             Dimension          dynamic                 CSG

XmNmarginTop               XmCMarginTop               Dimension          dynamic                 CSG

XmNmarginWidth             XmCMarginWidth             Dimension          dynamic                 CSG

XmNmnemonic                XmCMnemonic                KeySym             NULL                    CSG

XmNmnemonicCharSet         XmCMnemonicCharSet         String             XmFONTLIST_DEFAULT_TAG  CSG

XmNrecomputeSize           XmCRecomputeSize           Boolean            True                    CSG

XmNstringDirection         XmCStringDirection         XmStringDirection  dynamic                 CSG



XmPrimitive Resource Set

Name                   Class                  Type              Default               Access

XmNbottomShadowColor   XmCBottomShadowColor   Pixel             dynamic               CSG

XmNbottomShadowPixmap  XmCBottomShadowPixmap  Pixmap            XmUNSPECIFIED_PIXMAP  CSG

XmNforeground          XmCForeground          Pixel             dynamic               CSG

XmNhelpCallback        XmCCallback            XtCallbackList    NULL                  C

XmNhighlightColor      XmCHighlightColor      Pixel             dynamic               CSG

XmNhighlightOnEnter    XmCHighlightOnEnter    Boolean           False                 CSG

XmNhighlightPixmap     XmCHighlightPixmap     Pixmap            dynamic               CSG

XmNhighlightThickness  XmCHighlightThickness  Dimension         0                     CSG

XmNnavigationType      XmCNavigationType      XmNavigationType  XmNONE                CSG

XmNshadowThickness     XmCShadowThickness     Dimension         2                     CSG

XmNtopShadowColor      XmCTopShadowColor      Pixel             dynamic               CSG

XmNtopShadowPixmap     XmCTopShadowPixmap     Pixmap            dynamic               CSG

XmNtraversalOn         XmCTraversalOn         Boolean           dynamic               G

XmNunitType            XmCUnitType            unsigned char     dynamic               CSG

XmNuserData            XmCUserData            XtPointer         NULL                  CSG



Core Resource Set

Name                           Class                          Type            Default               Access

XmNaccelerators                XmCAccelerators                XtAccelerators  dynamic               CSG

XmNancestorSensitive           XmCSensitive                   Boolean         dynamic               G

XmNbackground                  XmCBackground                  Pixel           dynamic               CSG

XmNbackgroundPixmap            XmCPixmap                      Pixmap          XmUNSPECIFIED_PIXMAP  CSG

XmNborderColor                 XmCBorderColor                 Pixel           XtDefaultForeground   CSG

XmNborderPixmap                XmCPixmap                      Pixmap          XmUNSPECIFIED_PIXMAP  CSG

XmNborderWidth                 XmCBorderWidth                 Dimension       0                     CSG

XmNcolormap                    XmCColormap                    Colormap        dynamic               CG

XmNdepth                       XmCDepth                       int             dynamic               CG

XmNdestroyCallback             XmCCallback                    XtCallbackList  NULL                  C

XmNheight                      XmCHeight                      Dimension       dynamic               CSG

XmNinitialResourcesPersistent  XmCInitialResourcesPersistent  Boolean         True                  C

XmNmappedWhenManaged           XmCMappedWhenManaged           Boolean         True                  CSG

XmNscreen                      XmCScreen                      Screen *        dynamic               CG

XmNsensitive                   XmCSensitive                   Boolean         True                  CSG

XmNtranslations                XmCTranslations                XtTranslations  dynamic               CSG

XmNwidth                       XmCWidth                       Dimension       dynamic               CSG

XmNx                           XmCPosition                    Position        0                     CSG

XmNy                           XmCPosition                    Position        0                     CSG

Callback Information

A pointer to the following structure is passed to each callback: 

typedef struct
{
   int    reason;
   XEvent * event;
} XmAnyCallbackStruct;
reason
Indicates why the callback was invoked.
event
Points to the XEvent that triggered the callback or is NULL if this callback was not triggered due to an XEvent.

Translations

XmCascadeButton includes translations from Primitive. XmCascadeButton includes the menu traversal translations from XmLabel. These translations may not directly correspond to a translation table.

Note that altering translations in #override or #augment mode is undefined.

The translations for a CascadeButton in a MenuBar are listed below. These translations may not directly correspond to a translation table. 

BSelect Press:    MenuBarSelect()
BSelect Release:  DoSelect()
KActivate:        KeySelect()
KSelect:          KeySelect()
KHelp:            Help()
MAny KCancel:     CleanupMenuBar()

The translations for a CascadeButton in a PullDown or Popup MenuPane are listed below. In a Popup menu system, BMenu also performs the BSelect actions. These translations may not directly correspond to a translation table. 

BSelect Press:    StartDrag()
BSelect Release:  DoSelect()
KActivate:        KeySelect()
KSelect:          KeySelect()
KHelp:            Help()
MAny KCancel:     CleanupMenuBar()

Action Routines

The XmCascadeButton action routines are described below:

CleanupMenuBar():
In a MenuBar, disarms the CascadeButton and the menu and, when the shell's keyboard focus policy is XmEXPLICT, restores keyboard focus to the widget that had the focus before the menu was entered.

In a toplevel Pulldown MenuPane from a MenuBar, unposts the menu, disarms the MenuBar CascadeButton and the MenuBar, and, when the shell's keyboard focus policy is XmEXPLICT, restores keyboard focus to the widget that had the focus before the MenuBar was entered. In other Pulldown MenuPanes, unposts the menu.

In a Popup MenuPane, unposts the menu and, when the shell's keyboard focus policy is XmEXPLICT, restores keyboard focus to the widget from which the menu was posted.

DoSelect():
Calls the callbacks in XmNcascadingCallback, posts the submenu attached to the CascadeButton and enables keyboard traversal within the menu. If the CascadeButton does not have a submenu attached, calls the callbacks in XmNactivateCallback, the CascadeButton is activated and all posted menus in the cascade are unposted.
Help():
Unposts all menus in the menu hierarchy and, when the shell's keyboard focus policy is XmEXPLICT, restores keyboard focus to the widget that had the focus before the menu system was entered. Calls the callbacks for XmNhelpCallback if any exist. If there are no help callbacks for this widget, this action calls the help callbacks for the nearest ancestor that has them.
KeySelect():
Calls the callbacks in XmNcascadingCallback, and posts the submenu attached to the CascadeButton if keyboard traversal is enabled in the menu. If the CascadeButton does not have a submenu attached, calls the callbacks in XmNactivateCallback, the CascadeButton is activated and all posted menus in the cascade are unposted.
MenuBarSelect():
Unposts any menus posted by the parent menu. Arms both the CascadeButton and the MenuBar, posts the associated submenu, and enables mouse traversal. If the menu is already active, this event disables keyboard traversal for the menu and returns the menu to mouse traversal mode.
StartDrag():
Arms the CascadeButton, posts the associated submenu, and enables mouse traversal. If the menu is already active, this event disables keyboard traversal for the menu and returns the menu to mouse traversal mode.

Additional Behavior

Posting a submenu calls the XmNcascadingCallback callbacks. This widget has the additional behavior described below:

<EnterWindow>:
If keyboard traversal is enabled does nothing. Otherwise, in a MenuBar that is armed, unposts any MenuPanes associated with another MenuBar entry, arms the CascadeButton, and posts the associated submenu. In other menus, arms the CascadeButton and posts the associated submenu after the delay specified by XmNmappingDelay.
<LeaveWindow>:
If keyboard traversal is enabled does nothing. Otherwise, in a MenuBar that is armed, disarms the CascadeButton if the submenu associated with the CascadeButton is not currently posted or if there is no submenu associated with the CascadeButton.

In other menus, if the pointer moves anywhere except into a submenu associated with the CascadeButton, the CascadeButton is disarmed and its submenu is unposted.

Virtual Bindings

The bindings for virtual keys are vendor specific. For information about bindings for virtual buttons and keys, see VirtualBindings(3X).

RELATED INFORMATION

Core(3X), XmCascadeButtonHighlight(3X), XmCreateCascadeButton(3X),XmCreateMenuBar(3X), XmCreatePulldownMenu(3X), XmCreatePopupMenu(3X), XmLabel(3X), XmPrimitive(3X), and XmRowColumn(3X).