XmCascadeButtonGadget(3X)XmCascadeButtonGadget(3X)NAMEXmCascadeButtonGadget — The CascadeButtonGadget widget class
SYNOPSIS
#include <Xm/CascadeBG.h>
VERSION
This page documents version 1.2 of the Motif library.
DESCRIPTION
CascadeButtonGadget links two MenuPanes, a MenuBar to a MenuPane, or an
OptionMenu 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, XmMENU_PULL‐
DOWN, or XmMENU_OPTION.
It is the only gadget that can have a Pulldown MenuPane attached to it
as a submenu. The submenu is displayed when this gadget is activated
within a PopupMenu, a PulldownMenu, or an OptionMenu. 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 an OptionMenu.
The default behavior associated with a CascadeButtonGadget depends on
the type of menu system in which it resides. By default, BSelect con‐
trols the behavior of the CascadeButtonGadget. In addition, BMenu con‐
trols the behavior of the CascadeButtonGadget if it resides in a Popup‐
Menu system. The actual mouse button used is determined by its RowCol‐
umn parent.
A CascadeButtonGadget'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 CascadeButtonGadget within a Pulldown or Popup MenuPane is armed
as the result of the user moving the mouse pointer into the gadget, it
does not immediately display its submenu. Instead, it waits a short
time to see if the arming was temporary (that is, the user was simply
passing through the gadget), or the user really wanted the submenu
posted. This delay is configurable via XmNmappingDelay.
CascadeButtonGadget provides a single mechanism for activating the gad‐
get from the keyboard. This mechanism is referred to as a keyboard
mnemonic. If a mnemonic has been specified for the gadget, the user
may activate it by simply typing the mnemonic while the CascadeButton‐
Gadget is visible. If the CascadeButtonGadget 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.
If a CascadeButtonGadget is in a Pulldown or Popup MenuPane and there
is a submenu attached, the XmNmarginBottom, XmNmarginLeft, XmNmargin‐
Right, and XmNmarginTop resources may enlarge to accommodate XmNcas‐
cadePixmap. XmNmarginWidth defaults to 6 if this resource is in a
MenuBar; otherwise, it takes LabelGadget's default, which is 2.
Classes
CascadeButtonGadget inherits behavior and resources from Object, Rec‐
tObj, XmGadget, and XmLabelGadget classes.
The class pointer is xmCascadeButtonGadgetClass.
The class name is XmCascadeButtonGadget.
New Resources
The following table defines a set of widget resources used by the pro‐
grammer to specify data. The programmer can also set the resource val‐
ues 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).
XmCascadeButtonGadget
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
Specifies the list of callbacks that is called when the user activates
the CascadeButtonGadget, 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 gadget. The specific mouse button depends
on information in the RowColumn parent. The reason sent by the call‐
back is XmCR_ACTIVATE. Specifies the cascade pixmap displayed on one
end of the gadget when a CascadeButtonGadget is used within a Popup or
Pulldown MenuPane and a submenu is attached. The LabelGadget class
resources XmNmarginBottom, XmNmarginLeft, XmNmarginRight, and XmN‐
marginTop may be modified to ensure that room is left for the cascade
pixmap. The default cascade pixmap in menus other than option menus is
an arrow pointing to the side of the menu where the submenu will
appear. The default for the CascadeButtonGadget in an option menu is
XmUNSPECIFIED_PIXMAP. Specifies the list of callbacks that is called
just prior to the mapping of the submenu associated with the Cascade‐
ButtonGadget. The reason sent by the callback is XmCR_CASCADING.
Specifies the amount of time, in milliseconds, between when a Cascade‐
ButtonGadget becomes armed and when it maps its submenu. This delay is
used only when the gadget is within a Popup or Pulldown MenuPane. The
value must not be negative. Specifies the widget ID for the Pulldown
MenuPane to be associated with this CascadeButtonGadget. The specified
MenuPane is displayed when the CascadeButtonGadget becomes armed. The
MenuPane must have been created with the appropriate parentage depend‐
ing on the type of menu used. See XmCreatePulldownMenu(3X), XmCre‐
atePopupMenu(3X), and XmCreateOptionMenu(3X) for more information on
the menu systems.
Inherited Resources
CascadeButtonGadget inherits behavior and resources from the following
superclasses. For a complete description of each resource, refer to
the man page for that superclass.
XmLabelGadget 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 dynamic CSG
XmNrecomputeSize XmCRecomputeSize Boolean True CSG
XmNstringDirection XmCStringDirection XmStringDirection dynamic CSG
XmGadget Resource Set
Name Class Type Default Access
────────────────────────────────────────────────────────────────────────────────────
XmNbottomShadowColor XmCBottomShadowColor Pixel dynamic G
XmNhelpCallback XmCCallback XtCallbackList NULL C
XmNhighlightColor XmCHighlightColor Pixel dynamic G
XmNhighlightOnEnter XmCHighlightOnEnter Boolean False CSG
XmNhighlightThickness XmCHighlightThickness Dimension 0 CSG
XmNnavigationType XmCNavigationType XmNavigationType XmNONE CSG
XmNshadowThickness XmCShadowThickness Dimension 2 CSG
XmNtopShadowColor XmCTopShadowColor Pixel dynamic G
XmNtraversalOn XmCTraversalOn Boolean True CSG
XmNunitType XmCUnitType unsigned char dynamic CSG
XmNuserData XmCUserData XtPointer NULL CSG
RectObj Resource Set
Name Class Type Default Access
─────────────────────────────────────────────────────────────────────
XmNancestorSensitive XmCSensitive Boolean dynamic G
XmNborderWidth XmCBorderWidth Dimension 0 CSG
XmNheight XmCHeight Dimension dynamic CSG
XmNsensitive XmCSensitive Boolean True CSG
XmNwidth XmCWidth Dimension dynamic CSG
XmNx XmCPosition Position 0 CSG
XmNy XmCPosition Position 0 CSG
Object Resource Set
Name Class Type Default Access
─────────────────────────────────────────────────────────────────────
XmNdestroyCallback XmCCallback XtCallbackList NULL C
Callback Information
A pointer to the following structure is passed to each callback: type‐
def struct { int reason; XEvent * event; } XmAnyCallback‐
Struct; Indicates why the callback was invoked. Points to the XEvent
that triggered the callback or is NULL if this callback was not trig‐
gered by an XEvent.
Behavior
XmCascadeButtonGadget includes behavior from XmGadget. XmCascadeButton
includes the menu traversal behavior from XmLabel. Additional XmCas‐
cadeButtonGadget behavior is described below (in a Popup menu system,
BMenu also performs the BSelect actions): Unposts any menus posted by
the parent menu. Arms the CascadeButtonGadget, posts the associated
submenu, enables mouse traversal, and, in a MenuBar, arms the MenuBar.
If the menu is already active, this event disables keyboard traversal
for the menu and returns the menu to mouse traversal mode. Calls the
callbacks in XmNcascadingCallback, posts the submenu attached to the
CascadeButtonGadget and enables keyboard traversal within the menu. If
the CascadeButtonGadget does not have a submenu attached, calls the
callbacks in XmNactivateCallback, the CascadeButtonGadget is activated
and all posted menus in the cascade are unposted. Calls the callbacks
in XmNcascadingCallback, and posts the submenu attached to the Cascade‐
ButtonGadget if keyboard traversal is enabled in the menu. If the Cas‐
cadeButtonGadget does not have a submenu attached, calls the callbacks
in XmNactivateCallback, the CascadeButtonGadget is activated and all
posted menus in the cascade are unposted. This action applies only to
gadgets in MenuBars, PulldownMenus, and PopupMenus. For a CascadeBut‐
tonGadget in an OptionMenu, if the parent is a manager, this action
passes the event to the parent. Calls the callbacks in XmNcascading‐
Callback, and posts the submenu attached to the CascadeButtonGadget if
keyboard traversal is enabled in the menu. If the CascadeButtonGadget
does not have a submenu attached, calls the callbacks in XmNactivate‐
Callback, the CascadeButtonGadget is activated and all posted menus in
the cascade are unposted. 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. In a MenuBar, dis‐
arms the CascadeButtonGadget and the menu and, when the shell's key‐
board focus policy is XmEXPLICT, restores keyboard focus to the widget
that had the focus before the menu was entered. For a CascadeButton‐
Gadget in an OptionMenu, if the parent is a manager, this action passes
the event to the parent.
In a toplevel Pulldown MenuPane from a MenuBar, unposts the menu, dis‐
arms the MenuBar CascadeButton and the MenuBar, and, when the shell's
keyboard focus policy is XmEXPLICT, restores keyboard focus to the wid‐
get that had the focus before the MenuBar was entered. In other Pull‐
down MenuPanes, unposts the menu.
In a Popup MenuPane, unposts the menu and restores keyboard focus to
the widget from which the menu was posted. If keyboard traversal is
enabled does nothing. Otherwise, in a MenuBar, unposts any MenuPanes
associated with another MenuBar entry, arms the CascadeButtonGadget,
and posts the associated submenu. In other menus, arms the CascadeBut‐
tonGadget and posts the associated submenu after the delay specified by
XmNmappingDelay. If keyboard traversal is enabled does nothing. Oth‐
erwise, in a MenuBar, disarms the CascadeButtonGadget if the submenu
associated with the CascadeButtonGadget is not currently posted or if
there is no submenu associated with the CascadeButtonGadget.
In other menus, if the pointer moves anywhere except into a submenu
associated with the CascadeButtonGadget, the CascadeButtonGadget 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 INFORMATIONObject(3X), RectObj(3X), XmCascadeButtonHighlight(3), XmCreateCascade‐
ButtonGadget(3X), XmCreatePulldownMenu(3X), XmCreatePopupMenu(3X),
XmCreateOptionMenu(3X),XmGadget(3X), XmLabelGadget(3X), and XmRowCol‐
umn(3X).
XmCascadeButtonGadget(3X)
