NAME

XmDisplay − The Display widget class

SYNOPSIS

#include <Xm/Display.h>

DESCRIPTION

The XmDisplay object is used by the Motif widgets to store information that is specific to a display.  It also allows the toolkit to access certain information on widget hierarchies that would otherwise be unavailable.  Each client has one XmDisplay object for each display it accesses. 

An XmDisplay object is automatically created when the application creates the first shell on a display (usually accomplished by a call to XtAppInitialize or XtAppCreateShell).  It is not necessary to create an XmDisplay object by any other means.  An application can use the function XmGetXmDisplay to obtain the widget ID of the XmDisplay object for a given display. 

An application cannot supply initial values for XmDisplay resources as arguments to a call to any function that creates widgets.  The application or user can supply initial values in a resource file.  After creating the first shell on the display, the application can use XmGetXmDisplay to obtain the widget ID of the XmDisplay object and then call XtSetValues to set the XmDisplay resources. 

XmDisplay resources specify the drag protocol style for a client participating in drag and drop transactions.  There are two basic protocol types, preregister and dynamic.  When a preregister protocol is used, the toolkit handles any communication between the initiator and receiver clients, and displays the appropriate drag-over and drag-under visual effects.  A client registers its drop sites in advance and this information is stored in a property for each top-level window.  When the drag pointer enters a top level window, the drop site information is read by the initiator.  A dynamic protocol allows the source and destination clients to dynamically communicate drag and drop state information between each other, and to update their respective visuals accordingly.  The toolkit provides drop site information as the pointer passes over any given drop site.  In this mode, a receiver can supply a procedure to generate its own drag-under effects. 

Classes

Display inherits behavior and resources from Core, Composite, Shell, WMShell, VendorShell, TopLevelShell, and ApplicationShell classes. 

The class pointer is xmDisplayClass. 

The class name is XmDisplay. 

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 an .Xdefaults file, remove the XmN or XmC prefix and use the remaining letters.  To specify one of the defined values for a resource in an .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). 

XmNdefaultVirtualBindings
Specifies the default virtual bindings for the display. Following is an example of a specification for the defaultVirtualBindings resource in a resource file:

∗defaultVirtualBindings: \
osfBackSpace:<Key>BackSpace \n\
osfInsert:<Key>InsertChar \n\
...
osfDelete:<Key>DeleteChar

XmNdragInitiatorProtocolStyle
Specifies the drag and drop protocol requirements or preference when the client is an initiator.  The possible values are

XmDRAG_PREREGISTER
As an initiator, this client does not use the dynamic protocol and can only arrange visual effects with receivers who provide preregistered information.

XmDRAG_DYNAMIC
As an initiator, this client does not make use of any preregistered drop site information made available by other clients, and can only arrange visual effects with receivers who use the dynamic protocol.

XmDRAG_NONE
Specifies that drag and drop is disabled for this client.

XmDRAG_DROP_ONLY
As an initiator, this client does not use either the preregistered drop site information or the dynamic protocol.  It supports dragging, and any time the cursor is over a client that supports drag and drop, valid feedback is provided.  There are no other visual effects.

XmDRAG_PREFER_DYNAMIC
As an initiator, this client can support both the preregister and dynamic protocols, but prefers to use dynamic protocols whenever possible in order to provide high-quality drag-under feedback.

XmDRAG_PREFER_PREREGISTER
As an initiator, this client can support both the preregister and dynamic protocols, but prefers to use the preregister protocol whenever possible in order to accommodate performance needs or to provide consistent drag-over feedback.

XmDRAG_PREFER_RECEIVER
Indicates that this client can support both preregister and dynamic protocols, but will defer to the preference of the receiver client. This value is valid only for the XmNdragInitiatorProtocolStyle resource, and is its default value.  Specifies the drag and drop protocol requirements or preference when this client is a receiver.  The values are

XmDRAG_PREREGISTER
As a receiver, this client preregisters drop site information and does not use the dynamic protocol.  It can only arrange visual effects with initiators who make use of the preregistered information.

XmDRAG_DYNAMIC
As a receiver, this client uses the dynamic protocol and does not preregister drop site information.  It can only arrange visual effects with initiators who use the dynamic protocol.

XmDRAG_NONE
Specifies that drag and drop is disabled for this client.

XmDRAG_DROP_ONLY
As a receiver, this client neither uses the dynamic protocol nor preregisters drop site information.  It supports dropping, and when dragging over this client, valid feedback is always provided, but there are no other visual effects.

XmDRAG_PREFER_DYNAMIC
As a receiver, this client can support both the preregister and dynamic protocols, but prefers to use dynamic protocol whenever possible in order to provide high-quality drag-under feedback.

XmDRAG_PREFER_PREREGISTER
As a receiver, this client can support both the preregister and dynamic protocols, but prefers to use the preregister protocol whenever possible in order to accommodate performance needs.

The actual protocol used between an initiator and a receiver is based on the protocol style of the receiver and initiator.  The decision matrix is as follows:

The value XmDRAG_NONE does not appear in the above matrix.  When specified for either the initiator or receiver side, XmDRAG_NONE implies that drag and drop transactions are not supported.  A value of XmDRAG_DROP_ONLY (Drop Only) results when an initiator and receiver cannot compromise protocol styles, that is, one client requires dynamic mode while the other can only support preregister mode, or if either explicitly has specified XmDRAG_DROP_ONLY. 

defaultButtonEmphasis
This resource specifies whether to change the look of the PushButton widget and gadget that have the XmNshowAsDefault resource set.  When the control is the default, the PushButton has an etched out button which is enclosed with another etched in border.  When this resource is "internal_highlight", the location cursor appears in between the two etched borders to minimize the space required.  When this resource is "external_highlight", the default PushButton draws the location cursor outside the second border. 

enableBtn1Transfer
When this resource is True, it specifies that the actions for selection and transfer are integrated on the Button1, and the extend selection actions are activated from Button2. This resource impacts the actions of the XmText, XmTextField, and XmList widgets.

enableButtonTab
When this resource is True, it specifies whether to modify the action for the TAB key (KNextField and KPrevField) to move as an arrow key until the boundary of a tab group is reached. When at the boundary of the tab group, the KNextField and KPrevField actions will move to the next or previous tab group, respectively. This resource affects the actions of XmPushButtons, XmArrowButtons, and XmDrawnButtons.

enableDragIcon
Specifies which set of icons be used for the system default cursors during drag and drop operations. When this resource is False, the standard Motif icons are used. When this resource is True, an alternate set of icons that human interface experts designed are used. This resource affects both the 16x16 icons and the 32x32 icons that are the system defaults for each of the XmScreen objects associated with this display.

enableEtchedInMenu
Specifies the shadowing of the button widgets and gadgets in menus when the control is activated. When enableEtchedInMenu is True, the selected menu control is drawn with the shadow etched in; this shadow style is consistent with the selected appearance of other button widgets outside of menus.  When enableEtchedInMenu is False, the selected menu control is drawn with the shadow etched out.  This resource impacts the appearance of PushButtons, ToggleButtons, and CascadeButtons when they are children of an XmMenu. 

enableMultiKeyBindings
Specifies whether to modify the widget and gadget translations to support some MS-Windows common key bindings. When this resource is False, the default, the translations are not modified. When this resource is True, the following XtNbaseTranslations resources are merged into the resource database. When an application has specified a XtNbaseTranslations resource, it will have precedence over these definitions.

∗XmArrowButton.baseTranslations: #override
<Key>F1 : Help()
c<Key>s : PrimitiveParentCancel()
<Key>Escape : PrimitiveParentCancel()
∗XmBulletinBoard.baseTranslations: #override
<Key>F1:ManagerGadgetHelp()
c<Key>s : ManagerParentCancel()
<Key>Escape : ManagerParentCancel()
∗XmCascadeButton.baseTranslations: #override
<Key>F1:Help()
c<Key>s : CleanupMenuBar()
<Key>Escape : CleanupMenuBar()
∗XmDragContext.baseTranslations : #override
<Key>F1:HelpDrag()
c<Key>s : CancelDrag()
<Key>Escape : CancelDrag()
∗XmDrawingArea.baseTranslations: #override
<Key>F1 : DrawingAreaInput() ManagerGadgetHelp()
c<Key>s : DrawingAreaInput() ManagerParentCancel()
<Key>Escape : DrawingAreaInput() ManagerParentCancel()
∗XmDrawnButton.baseTranslations: #override
<Key>F1:Help()
c<Key>s : PrimitiveParentCancel()
<Key>Escape : PrimitiveParentCancel()
∗XmFrame.baseTranslations: #override
c<Key>s : ManagerParentCancel()
<Key>Escape : ManagerParentCancel()
∗XmLabel.baseTranslations: #override
<Key>F1:Help()
c<Key>s : PrimitiveParentCancel()
<Key>Escape : PrimitiveParentCancel()
<Btn2Down>:
∗XmList.baseTranslations: #override
<Key>F1:PrimitiveHelp()
c<Key>s : ListKbdCancel()
<Key>Escape : ListKbdCancel()
∗XmManager.baseTranslations: #override
<Key>F1:ManagerGadgetHelp()
c<Key>s : ManagerParentCancel()
<Key>Escape : ManagerParentCancel()
∗XmPrimitive.baseTranslations: #override
<Key>F1:PrimitiveHelp()
c<Key>s : PrimitiveParentCancel()
<Key>Escape : PrimitiveParentCancel()
∗XmPushButton.baseTranslations: #override
<Key>F1:Help()
c<Key>s : PrimitiveParentCancel()
<Key>Escape : PrimitiveParentCancel()
<Btn2Down>:
∗XmRowColumn.baseTranslations: #override
<Key>F1:MenuHelp()
c<Key>s : ManagerParentCancel()
 <Key>Escape : ManagerParentCancel()
∗XmSash.baseTranslations: #override
<Key>F1:Help()
c<Key>s : PrimitiveParentCancel()
<Key>Escape : PrimitiveParentCancel()
∗XmScrollBar.baseTranslations: #override
<Key>F1:PrimitiveHelp()
c<Key>s : CancelDrag()
<Key>Escape : CancelDrag()
∗XmScrolledWindow.baseTranslations: #override
<Key>F1:ManagerGadgetHelp()
c<Key>s : ManagerParentCancel()
<Key>Escape : ManagerParentCancel()
∗XmTextField.baseTranslations: #override
<Key>F1: Help()
c<Key>s : process-cancel()
<Key>Escape : process-cancel()
c<Key>x : cut-clipboard()
c<Key>c : copy-clipboard()
c<Key>v : paste-clipboard()
s<Key>Delete : cut-clipboard()
c<Key>Insert : copy-clipboard()
s<Key>Insert : paste-clipboard()
∗XmText.baseTranslations: #override
<Key>F1: Help()
c<Key>s : process-cancel()
<Key>Escape : process-cancel()
c<Key>x : cut-clipboard()
c<Key>c : copy-clipboard()
c<Key>v : paste-clipboard()
s<Key>Delete : cut-clipboard()
c<Key>Insert : copy-clipboard()
s<Key>Insert : paste-clipboard()
∗XmToggleButton.baseTranslations: #override
<Key>F1: Help()
c<Key>s : PrimitiveParentCancel()
<Key>Escape : PrimitiveParentCancel()
<Btn2Down>:

From the user’s perspective, setting the enableMultiKeyBindings resource to True has the following affect:

• use of F1 function key for accessing help

• use both <Ctrl>s and Escape for canceling an operation

• disable drag from labels in XmLabel, XmPushButton, XmToggleButton, and XmScale widgets and gadgets

• use both <Ctrl>x and <Shift>Delete to cut text

• use both <Ctrl>c and <Ctrl>Insert to copy text

• use both <Ctrl>v and <Shift>Insert to paste text

enableToggleColor
Specifies whether the fill color of the ToggleButton widget and gadget uses the background or the highlight color. When enableToggleColor is True, the fill color uses the highlight color.  The highlight color makes it more obvious to the end user that the Toggle has been set.  When enableToggleColor is False, the fill color uses the background color.  This resource affects the appearance of all ToggleButton widgets and gadgets. 

enableToggleVisual
Specifies the visual appearance of the ToggleButton widget and gadgets. When this resource is True, the look specified by the ToggleButton’s XmNindicatorType resource is as follows:

• XmONE_OF_MANY - a shadowed circle

• XmN_OF_MANY - a shadowed square with a check mark when set

When this resource is False, the look specified by the ToggleButton’s XmNindicatorType resource is as follows:

• XmONE_OF_MANY - a shadowed diamond

• XmN_OF_MANY - a shadowed square

This resource affects the appearance of all ToggleButton widgets and gadgets. 

enableUnselectableDrag
Specifies whether the user can drag text that is not selectable such as the labels on buttons. The default is True so that the use can drag all text. When this resource is set to False, the text on Buttons, Labels, and Scales cannot be the source of a drag operation.

Inherited Resources

All of the superclass resources inherited by XmDisplay are designated N/A (not applicable). 

RELATED INFORMATION

ApplicationShell(3X), Composite(3X), Core(3X), TopLevelShell(3X), VendorShell(3X), WMShell(3X), XmGetXmDisplay(3X), and XmScreen(3X). 

Motif Release 1.2: May 1992  —  Last change: