XmCascadeButtonGadget - The CascadeButtonGadget widget class
#include <Xm/CascadeBG.h>
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_PULLDOWN, 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 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.
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 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 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, 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.
The class pointer is xmCascadeButtonGadgetClass.
The class name is XmCascadeButtonGadget.
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).
| 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 |
CascadeButtonGadget inherits behavior and resources from the following superclasses. For a complete description of each resource, refer to the man page for that superclass.
| 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 |
| 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 |
| 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 |
| Name | Class | Type | Default | Access |
|---|---|---|---|---|
| XmNdestroyCallback | XmCCallback | XtCallbackList | NULL | C |
A pointer to the following structure is passed to each callback:
typedef struct
{
int reason;
XEvent * event;
} XmAnyCallbackStruct;
XmCascadeButtonGadget includes behavior from XmGadget. XmCascadeButton includes the menu traversal behavior from XmLabel. Additional XmCascadeButtonGadget behavior is described below (in a Popup menu system, BMenu also performs the BSelect actions):
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 restores keyboard focus to the widget from which the menu was posted.
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.
The bindings for virtual keys are vendor specific. For information about bindings for virtual buttons and keys, see VirtualBindings(3X).
Object(3X), RectObj(3X), XmCascadeButtonHighlight(3), XmCreateCascadeButtonGadget(3X), XmCreatePulldownMenu(3X), XmCreatePopupMenu(3X), XmCreateOptionMenu(3X),XmGadget(3X), XmLabelGadget(3X), and XmRowColumn(3X).