XmDisplay(3X)
XmDisplay --The Display widget class
As shipped in IRIX 6.5.22. Unchanged since IRIX 6.5.
NAME XmDisplay --The Display widget class SYNOPSIS #include <Xm/Display.h> VERSION This page documents version 1.2 of the Motif library. 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 in- formation 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 XtAppIni- tialize or XtAppCreateShell). It is not necessary to create an XmDisplay object by any other means. An application can use the function XmGetXmDis- play to obtain the widget ID of the XmDisplay object for a given display. An application cannot supply initial values for XmDisplay resources as ar- guments 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 ob- tain 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 partici- pating 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 dy- namic protocol allows the source and destination clients to dynamically communicate drag and drop state information between each other, and to up- date 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 program- mer 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 re- maining letters (in either lowercase or uppercase, but include any under- scores 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). XmDisplay Resource Set Name Class Type Default Access ------------------------------------------------------------------------------------------------------------------- XmNdefaultVirtualBindings DefaultVirtualBindings String dynamic CG XmNdragInitiatorProtocolStyle XmCDragInitiatorProtocolStyle unsigned char XmDRAG_PREFER_RECEIVER CG XmNdragReceiverProtocolStyle XmCDragReceiverProtocolStyle unsigned char XmDRAG_PREFER_PREREGISTER CG XmNdefaultVirtualBindings Specifies the default virtual bindings for the display. Follow- ing is an example of a specification for the defaultVirtualBind- ings 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 preregis- tered 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 preregis- tered drop site information or the dynamic protocol. It sup- ports 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 pro- tocol 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 dy- namic protocols, but will defer to the preference of the re- ceiver client. This value is valid only for the XmNdragInitia- torProtocolStyle resource, and is its default value. XmNdragReceiverProtocolStyle 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 vi- sual 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 vi- sual 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: Drag Initiator Drag Receiver Protocol Style Protocol Style ---------------------------------------------------------------- Preregister Prefer Preregister Prefer Dynamic Dynamic ----------------------------------------------------------------------------------- Preregister Preregister Preregister Preregister Drop Only ----------------------------------------------------------------------------------- Prefer Preregister Preregister Preregister Preregister Dynamic ----------------------------------------------------------------------------------- Prefer Receiver Preregister Preregister Dynamic Dynamic ----------------------------------------------------------------------------------- Prefer Dynamic Preregister Dynamic Dynamic Dynamic ----------------------------------------------------------------------------------- Dynamic Drop Only Dynamic Dynamic Dynamic The value XmDRAG_NONE does not appear in the above matrix. When specified for either the initiator or receiver side, Xm- DRAG_NONE implies that drag and drop transactions are not sup- ported. 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. 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), Vendor- Shell(3X), WMShell(3X), XmGetXmDisplay(3X), and XmScreen(3X). XmDisplay(3X)