NAME
XmCascadeButtonGadget — The CascadeButtonGadget widget class
SYNOPSIS
#include <Xm/CascadeBG.h>
DESCRIPTION
CascadeButtonGadget links two menu panes, a MenuBar to a menu pane, or
an OptionMenu to a menu pane.
It is used in menu systems and must have a RowColumn parent with its
XmNrowColumnType resource set to XmMENU_BAR, XmMENU_POPUP,
XmMENU_PULLDOWN, or XmMENU_OPTION.
It is the only gadget that can have a Pulldown menu pane 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 menu pane; or it can include only a label or a pixmap
when it is in an OptionMenu. The positioning of the PulldownMenu with
respect to the CascadeButton depends on the XmNlayoutDirection resource
of the MenuShell.
The default behavior associated with a CascadeButtonGadget depends on
the type of menu system in which it resides. By default, BSelect
controls the behavior of the CascadeButtonGadget. In addition, BMenu
controls the behavior of the CascadeButtonGadget if it resides in a
PopupMenu system. The actual mouse button used is determined by its
RowColumn parent. BMenu also performs the BSelect actions in all types
of menu systems.
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 menu pane 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 using XmNmappingDelay.
CascadeButtonGadget provides a single mechanism for activating the
gadget 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
CascadeButtonGadget is visible. If the CascadeButtonGadget is in a
MenuBar and the MenuBar does not have focus, the MAlt modifier must be
pressed with the mnemonic. Mnemonics are typically used to interact
with a menu using the keyboard.
If a CascadeButtonGadget is in a Pulldown or Popup menu pane 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 LabelGadget’s default, which is 2.
CascadeButtonGadget uses the XmQTmenuSystem and XmQTspecifyRenderTable
traits.
Classes
CascadeButtonGadget inherits behavior, resources, and traits from the
Object, RectObj, 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
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).
+---------------------------------------------------------------------------+
| | 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 |
+---------------------+-----------------+----------------+---------+--------+
+---------------------+-----------------+----------------+---------+--------+
XmNactivateCallback
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 when a mouse button
is released or when the mnemonic associated with the gadget
is typed. 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
gadget when a CascadeButtonGadget is used within a Popup or
Pulldown menu pane and a submenu is attached. The
LabelGadget class resources XmNmarginBottom, XmNmarginLeft,
XmNmarginRight, and XmNmarginTop 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.
The positioning of the cascade pixmap to either the left of
right of the widget, and the direction of the arrow, depend
on the XmNlayoutDirection resource of the MenuShell.
XmNcascadingCallback
Specifies the list of callbacks that is called just prior to
the mapping of the submenu associated with the
CascadeButtonGadget. The reason sent by the callback is
XmCR_CASCADING.
XmNmappingDelay
Specifies the amount of time, in milliseconds, between when a
CascadeButtonGadget becomes armed and when it maps its
submenu. This delay is used only when the gadget is within a
Popup or Pulldown menu pane. The value must not be negative.
XmNsubMenuId
Specifies the widget ID for the Pulldown menu pane to be
associated with this CascadeButtonGadget. The specified menu
pane is displayed when the CascadeButtonGadget becomes armed.
The menu pane must have been created with the appropriate
parentage depending on the type of menu used. See
XmCreatePulldownMenu(3), XmCreatePopupMenu(3), and
XmCreateOptionMenu(3) for more information on the menu
systems.
Inherited Resources
CascadeButtonGadget inherits behavior and resources from the
superclasses described in the following tables. For a complete
description of each resource, refer to the reference 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 |
+--------------------------+---------------------------+-------------------+----------------------+--------+
|XmNrenderTable | XmCRenderTable | XmRenderTable | dynamic | CSG |
+--------------------------+---------------------------+-------------------+----------------------+--------+
|XmNstringDirection | XmCStringDirection | XmStringDirection | dynamic | CSG |
+--------------------------+---------------------------+-------------------+----------------------+--------+
+--------------------------+---------------------------+-------------------+----------------------+--------+
+-------------------------------------------------------------------------------------------------+
| | XmGadget Resource Set | | |
|Name | Class | Type | Default | Access |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNbackground | XmCBackground | Pixel | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNbackgroundPixmap | XmCPixmap | Pixmap | XmUNSPECIFIED_PIXMAP | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNbottomShadowColor | XmCBottomShadowColor | Pixel | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNbottomShadowPixmap | XmCBottomShadowPixmap | Pixmap | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNhelpCallback | XmCCallback | XtCallbackList | NULL | C |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNforeground | XmCForeground | Pixel | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNhighlightColor | XmCHighlightColor | Pixel | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNhighlightOnEnter | XmCHighlightOnEnter | Boolean | False | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNhighlightPixmap | XmCHighlightPixmap | Pixmap | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNhighlightThickness | XmCHighlightThickness | Dimension | 0 | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNlayoutDirection | XmNCLayoutDirection | XmDirection | dynamic | CG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNnavigationType | XmCNavigationType | XmNavigationType | XmNONE | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNshadowThickness | XmCShadowThickness | Dimension | 2 | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNtopShadowColor | XmCTopShadowColor | Pixel | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|XmNtopShadowPixmap | XmCTopShadowPixmap | Pixmap | dynamic | CSG |
+----------------------+-----------------------+------------------+----------------------+--------+
|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 | N/A |
+---------------------+----------------+-----------+---------+--------+
|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:
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 by an XEvent
Behavior
XmCascadeButtonGadget includes behavior from XmGadget. XmCascadeButton
includes the menu traversal behavior from XmLabel. Additional
XmCascadeButtonGadget behavior is described in the following list (in a
Popup menu system, <Btn3> also performs the <Btn1> actions).
<Btn1Down>:
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.
<Btn1Up>: 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, this
action calls the callbacks in XmNactivateCallback, activates
the CascadeButtonGadget, and unposts all posted menus in the
cascade.
<Key><osfActivate>:
Calls the callbacks in XmNcascadingCallback, 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, this action calls the
callbacks in XmNactivateCallback, activates the
CascadeButtonGadget, and unposts all posted menus in the
cascade. This action applies only to gadgets in MenuBars,
PulldownMenus, and PopupMenus. For a CascadeButtonGadget in
an OptionMenu, if the parent is a manager, this action passes
the event to the parent.
<Key><osfSelect>:
Calls the callbacks in XmNcascadingCallback, 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, this action calls the
callbacks in XmNactivateCallback, activates the
CascadeButtonGadget, and unposts all posted menus in the
cascade.
<Key><osfHelp>:
Unposts all menus in the menu hierarchy and, when the shell’s
keyboard focus policy is XmEXPLICIT, 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.
<Key><osfCancel>:
In a MenuBar, disarms the CascadeButtonGadget and the menu
and, when the shell’s keyboard focus policy is XmEXPLICIT,
restores keyboard focus to the widget that had the focus
before the menu was entered. For a CascadeButtonGadget 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, disarms the MenuBar CascadeButton and the MenuBar, and,
when the shell’s keyboard focus policy is XmEXPLICIT,
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 restores keyboard
focus to the widget from which the menu was posted.
<Enter>: 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
CascadeButtonGadget and posts the associated submenu after
the delay specified by XmNmappingDelay.
<Leave>: If keyboard traversal is enabled does nothing. Otherwise, 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(3).
RELATED
Object(3), RectObj(3), XmCascadeButtonHighlight(3),
XmCreateCascadeButtonGadget(3), XmCreatePulldownMenu(3),
XmCreatePopupMenu(3), XmCreateOptionMenu(3), XmGadget(3),
XmLabelGadget(3), and XmRowColumn(3).
XmCascadeButtonGadget(library call)