OSF/Motif

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

XmNactivateCallback

Class: XmCCallback
Default: NULL
Type:  XtCallbackList
Access: C

XmNcascadePixmap

Class: XmCPixmap
Default: dynamic
Type:  Pixmap
Access: CSG

XmNcascadingCallback

Class: XmCCallback
Default: NULL
Type:  XtCallbackList
Access: C

XmNmappingDelay

Class: XmCMappingDelay
Default: 180 ms
Type:  int
Access: CSG

XmNsubMenuId

Class: XmCMenuWidget
Default: NULL
Type:  Widget
Access: 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

XmNaccelerator

Class: XmCAccelerator
Default: NULL
Type:  String
Access: N/A

XmNacceleratorText

Class: XmCAcceleratorText
Default: NULL
Type:  XmString
Access: N/A

XmNalignment

Class: XmCAlignment
Default: dynamic
Type:  unsigned char
Access: CSG

XmNfontList

Class: XmCFontList
Default: dynamic
Type:  XmFontList
Access: CSG

XmNlabelInsensitivePixmap

Class: XmCLabelInsensitivePixmap
Default: XmUNSPECIFIED_PIXMAP
Type:  Pixmap
Access: CSG

XmNlabelPixmap

Class: XmCLabelPixmap
Default: XmUNSPECIFIED_PIXMAP
Type:  Pixmap
Access: CSG

XmNlabelString

Class: XmCXmString
Default: dynamic
Type:  XmString
Access: CSG

XmNlabelType

Class: XmCLabelType
Default: XmSTRING
Type:  unsigned char
Access: CSG

XmNmarginBottom

Class: XmCMarginBottom
Default: dynamic
Type:  Dimension
Access: CSG

XmNmarginHeight

Class: XmCMarginHeight
Default: 2
Type:  Dimension
Access: CSG

XmNmarginLeft

Class: XmCMarginLeft
Default: 0
Type:  Dimension
Access: CSG

XmNmarginRight

Class: XmCMarginRight
Default: dynamic
Type:  Dimension
Access: CSG

XmNmarginTop

Class: XmCMarginTop
Default: dynamic
Type:  Dimension
Access: CSG

XmNmarginWidth

Class: XmCMarginWidth
Default: dynamic
Type:  Dimension
Access: CSG

XmNmnemonic

Class: XmCMnemonic
Default: NULL
Type:  KeySym
Access: CSG

XmNmnemonicCharSet

Class: XmCMnemonicCharSet
Default: XmFONTLIST_DEFAULT_TAG
Type:  String
Access: CSG

XmNrecomputeSize

Class: XmCRecomputeSize
Default: True
Type:  Boolean
Access: CSG

XmNstringDirection

Class: XmCStringDirection
Default: dynamic
Type:  XmStringDirection
Access: CSG

XmPrimitive Resource Set

XmNbottomShadowColor

Class: XmCBottomShadowColor
Default: dynamic
Type:  Pixel
Access: CSG

XmNbottomShadowPixmap

Class: XmCBottomShadowPixmap
Default: XmUNSPECIFIED_PIXMAP
Type:  Pixmap
Access: CSG

XmNforeground

Class: XmCForeground
Default: dynamic
Type:  Pixel
Access: CSG

XmNhelpCallback

Class: XmCCallback
Default: NULL
Type:  XtCallbackList
Access: C

XmNhighlightColor

Class: XmCHighlightColor
Default: dynamic
Type:  Pixel
Access: CSG

XmNhighlightOnEnter

Class: XmCHighlightOnEnter
Default: False
Type:  Boolean
Access: CSG

XmNhighlightPixmap

Class: XmCHighlightPixmap
Default: dynamic
Type:  Pixmap
Access: CSG

XmNhighlightThickness

Class: XmCHighlightThickness
Default: 0
Type:  Dimension
Access: CSG

XmNnavigationType

Class: XmCNavigationType
Default: XmNONE
Type:  XmNavigationType
Access: CSG

XmNshadowThickness

Class: XmCShadowThickness
Default: 2
Type:  Dimension
Access: CSG

XmNtopShadowColor

Class: XmCTopShadowColor
Default: dynamic
Type:  Pixel
Access: CSG

XmNtopShadowPixmap

Class: XmCTopShadowPixmap
Default: dynamic
Type:  Pixmap
Access: CSG

XmNtraversalOn

Class: XmCTraversalOn
Default: dynamic
Type:  Boolean
Access: G

XmNunitType

Class: XmCUnitType
Default: dynamic
Type:  unsigned char
Access: CSG

XmNuserData

Class: XmCUserData
Default: NULL
Type:  XtPointer
Access: CSG

Core Resource Set

XmNaccelerators

Class: XmCAccelerators
Default: dynamic
Type:  XtAccelerators
Access: CSG

XmNancestorSensitive

Class: XmCSensitive
Default: dynamic
Type:  Boolean
Access: G

XmNbackground

Class: XmCBackground
Default: dynamic
Type:  Pixel
Access: CSG

XmNbackgroundPixmap

Class: XmCPixmap
Default: XmUNSPECIFIED_PIXMAP
Type:  Pixmap
Access: CSG

XmNborderColor

Class: XmCBorderColor
Default: XtDefaultForeground
Type:  Pixel
Access: CSG

XmNborderPixmap

Class: XmCPixmap
Default: XmUNSPECIFIED_PIXMAP
Type:  Pixmap
Access: CSG

XmNborderWidth

Class: XmCBorderWidth
Default: 0
Type:  Dimension
Access: CSG

XmNcolormap

Class: XmCColormap
Default: dynamic
Type:  Colormap
Access: CG

XmNdepth

Class: XmCDepth
Default: dynamic
Type:  int
Access: CG

XmNdestroyCallback

Class: XmCCallback
Default: NULL
Type:  XtCallbackList
Access: C

XmNheight

Class: XmCHeight
Default: dynamic
Type:  Dimension
Access: CSG

XmNinitialResourcesPersistent

Class: XmCInitialResourcesPersistent
Default: True
Type:  Boolean
Access: C

XmNmappedWhenManaged

Class: XmCMappedWhenManaged
Default: True
Type:  Boolean
Access: CSG

XmNscreen

Class: XmCScreen
Default: dynamic
Type:  Screen ∗
Access: CG

XmNsensitive

Class: XmCSensitive
Default: True
Type:  Boolean
Access: CSG

XmNtranslations

Class: XmCTranslations
Default: dynamic
Type:  XtTranslations
Access: CSG

XmNwidth

Class: XmCWidth
Default: dynamic
Type:  Dimension
Access: CSG

XmNx

Class: XmCPosition
Default: 0
Type:  Position
Access: CSG

XmNy

Class: XmCPosition
Default: 0
Type:  Position
Access: 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). 

SEE ALSO

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