|
|
XmDragContext(3X)
Contents
|
XmDragContext - The DragContext widget class
#include <Xm/DragDrop.h>
DragContexts are special widgets used in drag and drop
transactions. A DragContext is implemented as a widget,
but a client does not explicitly create a DragContext widget.
Instead, a client initiates a drag and drop transaction
by calling XmDragStart, and this routine initializes
and returns a DragContext widget. There is a unique DragContext
for each drag operation. The toolkit frees a
DragContext when a transaction is complete; therefore, an
application programmer should not explicitly destroy a
DragContext.
Initiator and receiver clients both use DragContexts to
track the state of a transaction. When the initiator and
receiver of a transaction are in the same client, they
share the same DragContext instance. If they are in different
clients, there are two separate DragContexts. In
this case, the initiator calls XmDragStart and the toolkit
provides a DragContext for the receiver client. The only
resources pertinent to the receiver are XmNexportTargets
and XmNnumExportTargets. These can both be passed as
arguments to the XmDropSiteRetrieve function to obtain
information about the current drop site.
In general, in order to receive data, a drop site must
share at least one target type and operation in common
with a drag source. The DragContext resource, XmNexportTargets,
identifies the selection targets for the drag
source. These export targets are compared with the XmNimportTargets
resource list specified by a drop site. The
DragContext resource, XmNdragOperations, identifies the
valid operations that can be applied to the source data by
the initiator. The drop site counterpart resource is XmNdropSiteOperations,
which indicates a drop site's supported
operations.
A client uses DragIcon widgets to define the drag-over
animation effects associated with a given drag and drop
transaction. An initiator specifies a set of drag icons,
selects a blending model, and sets foreground and background
cursor colors with DragContext resources.
The type of drag-over visual used to represent a drag
operation depends on the drag protocol style. In preregister
mode, the server is grabbed, and either a cursor or
a pixmap may be used as a drag-over visual. In dynamic
mode, drag-over visuals must be implemented with the X
cursor. If the resulting drag protocol style is Drop Only
or None and the XmNdragInitiatorProtocolStyle is
XmDRAG_DYNAMIC or XmDRAG_PREFER_DYNAMIC, then a dynamic
visual style (cursor) is used. Otherwise, a preregister
visual style is used.
Classes [Toc] [Back]
DragContext inherits behavior and resources from Core.
The class pointer is xmDragContextClass.
The class name is XmDragContext.
New Resources [Toc] [Back]
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).
XmDragContext Resource Set [Toc] [Back]
Class: XmCBlendModel
Default: XmBLEND_ALL
Type: unsigned char
Access: CG
Class: XmCClientData
Default: NULL
Type: XtPointer
Access: CSG
Class: XmCConvertProc
Default: NULL
Type: XtConvertSelectionIncrProc
Access: CSG
Class: XmCCursorBackground
Default: dynamic
Type: Pixel
Access: CSG
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: CSG
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCDragOperations
Default: XmDROP_COPY XmDROP_MOVE
Type: unsigned char
Access: C
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCExportTargets
Default: NULL
Type: Atom *
Access: CSG
Class: XmCIncremental
Default: False
Type: Boolean
Access: CSG
Class: XmCCursorForeground
Default: dynamic
Type: Pixel
Access: CSG
Class: XmCCursorForeground
Default: dynamic
Type: Pixel
Access: CSG
Class: XmCNumExportTargets
Default: 0
Type: Cardinal
Access: CSG
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCOperationCursorIcon
Default: dynamic
Type: Widget
Access: CSG
Class: XmCSourceCursorIcon
Default: dynamic
Type: Widget
Access: CSG
Class: XmCSourcePixmapIcon
Default: dynamic
Type: Widget
Access: CSG
Class: XmCStateCursorIcon
Default: dynamic
Type: Widget
Access: CSG
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCCursorForeground
Default: dynamic
Type: Pixel
Access: CSG
Specifies which combination of DragIcons are
blended to produce a drag-over visual. Blends all
three DragIcons--the source, state and operation
icon. The icons are layered from top to bottom with
the operation icon on top and the source icon on
the bottom. The hotspot is derived from the state
icon. Blends the state and source icons only. The
hotspot is derived from the state icon. Specifies
that only the source icon is used, which the initiator
updates as required. Specifies that no
drag-over visual is generated. The client tracks
the drop site status through callback routines and
updates the drag-over visuals as necessary. Specifies
the client data to be passed to the XmNconvertProc
when it is invoked. Specifies a procedure
of type XtConvertSelectionIncrProc that converts
the source data to the format(s) requested by the
receiver client. The widget argument passed to this
procedure is the DragContext widget. The selection
atom passed is _MOTIF_DROP. If XmNincremental is
False, the procedure should ignore the max_length,
client_data, and request_id arguments and should
handle the conversion atomically. Data returned by
XmNconvertProc must be allocated using XtMalloc and
will be freed automatically by the toolkit after
the transfer. For additional information on selection
conversion procedures, see X Toolkit Intrinsics--C
Language Interface. Specifies the background
pixel value of the cursor. Specifies the
foreground pixel value of the cursor when the state
icon is not blended. This resource defaults to the
foreground color of the widget passed to the
XmDragStart function. Specifies the list of callbacks
that are called when the transaction is completed.
The type of the structure whose address is
passed to this callback is XmDragDropFinishCallbackStruct.
The reason sent by the callback is
XmCR_DRAG_DROP_FINISH. Specifies the list of callbacks
that are invoked when the pointer moves. The
type of structure whose address is passed to this
callback is XmDragMotionCallbackStruct. The reason
sent by the callback is XmCR_DRAG_MOTION.
Specifies the set of valid operations associated
with an initiator client for a drag transaction.
This resource is a bit mask that is formed by combining
one or more of the following values using a
bitwise operation such as inclusive OR (|):
XmDROP_COPY, XmDROP_LINK, XmDROP_MOVE. The value
XmDROP_NOOP for this resource indicates that no
operations are valid. For Text and TextField widgets,
this resource is set to XmDROP_COPY |
XmDROP_MOVE; for List widgets, it is set to
XmDROP_COPY. Specifies the list of callbacks that
are invoked when the drop is completed. The type
of the structure whose address is passed to this
callback is XmDropFinishCallbackStruct. The reason
sent by the callback is XmCR_DROP_FINISH. Specifies
the list of callbacks that are invoked when
the pointer enters a drop site. The type of the
structure whose address is passed to this callback
is XmDropSiteEnterCallbackStruct. The reason sent
by the callback is XmCR_DROP_SITE_ENTER. Specifies
the list of callbacks that are invoked when the
pointer leaves a drop site. The type of the structure
whose address is passed to this callback is
XmDropSiteLeaveCallbackStruct. The reason sent by
the callback is XmCR_DROP_SITE_LEAVE. Specifies
the list of callbacks that are invoked when a drop
is initiated. The type of the structure whose
address is passed to this callback is XmDropStartCallbackStruct.
The reason sent by the callback is
XmCR_DROP_START. Specifies the list of target
atoms associated with this source. This resource
identifies the selection targets this source can be
converted to. Specifies a Boolean value that indicates
whether the transfer on the initiator side
uses the Xt incremental selection transfer mechanism
described in X Toolkit Intrinsics--C Language
Interface. If the value is True, the initiator
uses incremental transfer; if the value is False,
the initiator uses atomic transfer. Specifies the
foreground pixel value of the cursor when the state
is invalid. This resource defaults to the value of
the XmNcursorForeground resource. Specifies the
foreground pixel value of the cursor when the state
is none. This resource defaults to the value of
the XmNcursorForeground resource. Specifies the
number of entries in the list of export targets.
Specifies the list of callbacks that are invoked
when the drag is started and when the user requests
that a different operation be applied to the drop.
The type of the structure whose address is passed
to this callback is XmOperationChangedCallbackStruct.
The reason sent by the callback is
XmCR_OPERATION_CHANGED. Specifies the cursor icon
used to designate the type of operation performed
by the drag transaction. If NULL, XmScreen
resources provide default icons for copy, link, and
move operations. Specifies the cursor icon used to
represent the source when a dynamic visual style is
used. If NULL, the XmNdefaultSourceCursorIcon
resource of XmScreen provides a default cursor
icon. Specifies the pixmap icon used to represent
the source when a preregister visual style is used.
The icon is used in conjunction with the colormap
of the widget passed to XmDragStart. If NULL, XmNsourceCursorIcon
is used. Specifies the cursor
icon used to designate the state of a drop site. If
NULL, XmScreen resources provide default icons for
a valid, invalid, and no drop site condition.
Specifies the list of callbacks that are called
when the pointer enters a top-level window or root
window (due to changing screens). The type of the
structure whose address is passed to this callback
is XmTopLevelEnterCallbackStruct. The reason sent
by the callback is XmCR_TOP_LEVEL_ENTER. Specifies
the list of callbacks that are called when the
pointer leaves a top level window or the root window
(due to changing screens). The type of the
structure whose address is passed to this callback
is XmTopLevelLeaveCallbackStruct. The reason sent
by the callback is XmCR_TOP_LEVEL_LEAVE. Specifies
the foreground pixel value of the cursor designated
as a valid cursor icon.
Inherited Resources [Toc] [Back]
DragContext inherits behavior and resources from the following
superclass. For a complete description of each
resource, refer to the Core(3X) man page.
Core Resource Set [Toc] [Back]
Class: XmCAccelerators
Default: dynamic
Type: XtAccelerators
Access: CSG
Class: XmCSensitive
Default: dynamic
Type: Boolean
Access: G
Class: XmCBackground
Default: dynamic
Type: Pixel
Access: CSG
Class: XmCPixmap
Default: XmUNSPECIFIED_PIXMAP
Type: Pixmap
Access: CSG
Class: XmCBorderColor
Default: XtDefaultForeground
Type: Pixel
Access: CSG
Class: XmCPixmap
Default: XmUNSPECIFIED_PIXMAP
Type: Pixmap
Access: CSG
Class: XmCBorderWidth
Default: 0
Type: Dimension
Access: CSG
Class: XmCColormap
Default: dynamic
Type: Colormap
Access: CG
Class: XmCDepth
Default: dynamic
Type: int
Access: CG
Class: XmCCallback
Default: NULL
Type: XtCallbackList
Access: C
Class: XmCHeight
Default: dynamic
Type: Dimension
Access: CSG
Class: XmCInitialResourcesPersistent
Default: True
Type: Boolean
Access: C
Class: XmCMappedWhenManaged
Default: True
Type: Boolean
Access: CSG
Class: XmCScreen
Default: dynamic
Type: Screen *
Access: CG
Class: XmCSensitive
Default: True
Type: Boolean
Access: CSG
Class: XmCTranslations
Default: dynamic
Type: XtTranslations
Access: CSG
Class: XmCWidth
Default: dynamic
Type: Dimension
Access: CSG
Class: XmCPosition
Default: 0
Type: Position
Access: CSG
Class: XmCPosition
Default: 0
Type: Position
Access: CSG
Callback Information [Toc] [Back]
Each of the DragContext callbacks has an associated callback
structure.
A pointer to the following structure is passed to the XmNdragDropFinishCallback
callback. typedef struct {
int reason;
XEvent *event;
Time timeStamp; }XmDragDropFinishCallbackStruct,
*XmDragDropFinishCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the time at
which either the drag or the drop was completed.
A pointer to the following structure is passed to callbacks
for XmNdragMotionCallback. typedef struct {
int reason;
XEvent *event;
Time timeStamp;
unsigned char operation;
unsigned char operations;
unsigned char dropSiteStatus;
Position x;
Position y; }XmDragMotionCallbackStruct, *XmDragMotionCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the timestamp
of the logical event. Identifies an operation.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes operation to the
value of the operation member of the XmDragProcCallbackStruct
at the time the DropSite's XmNdragProc
returns.
If the toolkit has not called an XmNdragProc and
the pointer is within an active drop site, the
toolkit initializes operation by selecting an operation
from the bitwise AND of the initial value of
the operations member and the value of the DropSite's
XmNdropSiteOperations resource. The toolkit
searches this set first for XmDROP_MOVE, then for
XmDROP_COPY, then for XmDROP_LINK, and initializes
operation to the first operation it finds in the
set. If the toolkit finds none of these operations
in the set, it initializes operation to
XmDROP_NOOP.
If the toolkit has not called an XmNdragProc and
the pointer is not within an active drop site, the
toolkit initializes operation by selecting an operation
from the initial value of the operations member.
The toolkit searches this set first for
XmDROP_MOVE, then for XmDROP_COPY, then for
XmDROP_LINK, and initializes operation to the first
operation it finds in the set. If the toolkit finds
none of these operations in the set, it initializes
operation to XmDROP_NOOP. Indicates the set of
operations supported for the source data.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes operations to the
bitwise AND of the DropSite's XmNdropOperations and
the value of the operations member of the XmDragProcCallbackStruct
at the time the DropSite's XmNdragProc
returns. If the resulting set of operations
is empty, the toolkit initializes operations
to XmDROP_NOOP.
If the toolkit has not called an XmNdragProc and
the user does not select an operation (by pressing
a modifier key), the toolkit initializes operations
to the value of the DragContext's XmNdragOperations
resource.
If the toolkit has not called an XmNdragProc and
the user does select an operation, the toolkit initializes
operations to the bitwise AND of the corresponding
operation and the value of the DragContext's
XmNdragOperations resource. If the resulting
set of operations is empty, the toolkit initializes
operations to XmDROP_NOOP. Indicates whether or
not a drop site is valid.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes dropSiteStatus to
the value of the dropSiteStatus member of the
XmDragProcCallbackStruct at the time the DropSite's
XmNdragProc returns.
If the toolkit has not called an XmNdragProc, it
initializes dropSiteStatus as follows: the toolkit
initializes dropSiteStatus to XmNO_DROP_SITE if the
pointer is over an inactive drop site or is not
over a drop site. The toolkit initializes dropSiteStatus
to XmDROP_SITE_VALID if all the following
conditions are met: The pointer is over an
active drop site. The DragContext's XmNexportTargets
and the DropSite's XmNimportTargets are compatible.
The initial value of the operation member
is not XmDROP_NOOP.
Otherwise, the toolkit initializes dropSiteStatus
to XmDROP_SITE_INVALID.
A pointer to the following structure is passed for the
XmNdropFinishCallback callback: typedef struct {
int reason;
XEvent *event;
Time timeStamp;
unsigned char operation;
unsigned char operations;
unsigned char dropSiteStatus;
unsigned char dropAction;
unsigned char completionStatus; }XmDropFinishCallbackStruct,
*XmDropFinishCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the time at
which the drop was completed. Identifies an operation.
If the pointer is over an active drop site when the
drop begins, the toolkit initializes operation to
the value of the operation member of the XmDropProcCallbackStruct
at the time the DropSite's XmNdropProc
returns.
If the pointer is not over an active drop site when
the drop begins, the toolkit initializes operation
by selecting an operation from the initial value of
the operations member. The toolkit searches this
set first for XmDROP_MOVE, then for XmDROP_COPY,
then for XmDROP_LINK, and initializes operation to
the first operation it finds in the set. If it
finds none of these operations in the set, it initializes
operation to XmDROP_NOOP. Indicates the
set of operations supported for the source data.
If the pointer is over an active drop site when the
drop begins, the toolkit initializes operations to
the bitwise AND of the DropSite's XmNdropOperations
and the value of the operations member of the
XmDropProcCallbackStruct at the time the DropSite's
XmNdropProc returns. If the resulting set of operations
is empty, the toolkit initializes operations
to XmDROP_NOOP.
If the pointer is not over an active drop site when
the drop begins and if the user does not select an
operation (by pressing a modifier key), the toolkit
initializes operations to the value of the DragContext's
XmNdragOperations resource.
If the pointer is not over an active drop site when
the drop begins and if the user does select an
operation, the toolkit initializes operations to
the bitwise AND of the corresponding operation and
the value of the DragContext's XmNdragOperations
resource. If the resulting set of operations is
empty, the toolkit initializes operations to
XmDROP_NOOP. Indicates whether or not a drop site
is valid.
If the pointer is over an active drop site when the
drop begins, the toolkit initializes dropSiteStatus
to the value of the dropSiteStatus member of the
XmDropProcCallbackStruct at the time the DropSite's
XmNdropProc returns.
If the pointer is not over an active drop site when
the drop begins, the toolkit initializes dropSiteStatus
to XmNO_DROP_SITE. Identifies the drop
action. The values are: XmDROP, XmDROP_CANCEL,
XmDROP_HELP, and XmDROP_INTERRUPT. The value
XmDROP_INTERRUPT is currently unsupported; if specified,
it will be interpreted as an XmDROP_CANCEL.
An IN/OUT member that indicates the status of the
drop action. After the last callback procedure has
returned, the final value of this member determines
what visual transition effects will be applied.
There are two values: The drop was successful. The
drop was unsuccessful.
A pointer to the following structure is passed to callbacks
for XmNdropSiteEnterCallback: typedef struct {
int reason;
XEvent *event;
Time timeStamp;
unsigned char operation;
unsigned char operations;
unsigned char dropSiteStatus;
Position x;
Position y; }XmDropSiteEnterCallbackStruct,
*XmDropSiteEnterCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the time
the crossing event occurred. Identifies an operation.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes operation to the
value of the operation member of the XmDragProcCallbackStruct
at the time the DropSite's XmNdragProc
returns.
If the toolkit has not called an XmNdragProc, it
initializes operation by selecting an operation
from the bitwise AND of the initial value of the
operations member and the value of the DropSite's
XmNdropSiteOperations resource. The toolkit
searches this set first for XmDROP_MOVE, then for
XmDROP_COPY, then for XmDROP_LINK, and initializes
operation to the first operation it finds in the
set. If the toolkit finds none of these operations
in the set, it initializes operation to
XmDROP_NOOP. Indicates the set of operations supported
for the source data.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes operations to the
bitwise AND of the DropSite's XmNdropOperations and
the value of the operations member of the XmDragProcCallbackStruct
at the time the DropSite's XmNdragProc
returns. If the resulting set of operations
is empty, the toolkit initializes operations
to XmDROP_NOOP.
If the toolkit has not called an XmNdragProc and
the user does not select an operation (by pressing
a modifier key), the toolkit initializes operations
to the value of the DragContext's XmNdragOperations
resource.
If the toolkit has not called an XmNdragProc and
the user does select an operation, the toolkit initializes
operations to the bitwise AND of the corresponding
operation and the value of the DragContext's
XmNdragOperations resource. If the resulting
set of operations is empty, the toolkit initializes
operations to XmDROP_NOOP. Indicates whether or
not a drop site is valid.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes dropSiteStatus to
the value of the dropSiteStatus member of the
XmDragProcCallbackStruct at the time the DropSite's
XmNdragProc returns.
If the toolkit has not called an XmNdragProc, it
initializes dropSiteStatus as follows: the toolkit
initializes dropSiteStatus to XmDROP_SITE_VALID if
the DragContext's XmNexportTargets and the DropSite's
XmNimportTargets are compatible and if the
initial value of the operation member is not
XmDROP_NOOP. Otherwise, the toolkit initializes
dropSiteStatus to XmDROP_SITE_INVALID. Indicates
the x-coordinate of the pointer in root window
coordinates. Indicates the y-coordinate of the
pointer in root window coordinates.
A pointer to the following structure is passed to callbacks
for XmNdropSiteLeaveCallback. typedef struct {
int reason;
XEvent *event;
Time timeStamp; }XmDropSiteLeaveCallbackStruct,
*XmDropSiteLeaveCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the timestamp
of the logical event.
A pointer to the following structure is passed for the
XmNdropStartCallback callback: typedef struct {
int reason;
XEvent *event;
Time timeStamp;
unsigned char operation;
unsigned char operations;
unsigned char dropSiteStatus;
unsigned char dropAction;
Position x;
Position y; }XmDropStartCallbackStruct, *XmDropStartCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the time at
which the drag was completed. Identifies an operation.
If the pointer is over an active drop site when the
drop begins, the toolkit initializes operation to
the value of the operation member of the XmDropProcCallbackStruct
at the time the DropSite's XmNdropProc
returns.
If the pointer is not over an active drop site when
the drop begins, the toolkit initializes operation
by selecting an operation from the initial value of
the operations member. The toolkit searches this
set first for XmDROP_MOVE, then for XmDROP_COPY,
then for XmDROP_LINK, and initializes operation to
the first operation it finds in the set. If it
finds none of these operations in the set, it initializes
operation to XmDROP_NOOP. Indicates the
set of operations supported for the source data.
If the pointer is over an active drop site when the
drop begins, the toolkit initializes operations to
the bitwise AND of the DropSite's XmNdropOperations
and the value of the operations member of the
XmDropProcCallbackStruct at the time the DropSite's
XmNdropProc returns. If the resulting set of operations
is empty, the toolkit initializes operations
to XmDROP_NOOP.
If the pointer is not over an active drop site when
the drop begins and if the user does not select an
operation (by pressing a modifier key), the toolkit
initializes operations to the value of the DragContext's
XmNdragOperations resource.
If the pointer is not over an active drop site when
the drop begins and if the user does select an
operation, the toolkit initializes operations to
the bitwise AND of the corresponding operation and
the value of the DragContext's XmNdragOperations
resource. If the resulting set of operations is
empty, the toolkit initializes operations to
XmDROP_NOOP. Indicates whether or not a drop site
is valid.
If the pointer is over an active drop site when the
drop begins, the toolkit initializes dropSiteStatus
to the value of the dropSiteStatus member of the
XmDropProcCallbackStruct at the time the DropSite's
XmNdropProc returns.
If the pointer is not over an active drop site when
the drop begins, the toolkit initializes dropSiteStatus
to XmNO_DROP_SITE. An IN/OUT member that
identifies the drop action. The values are XmDROP,
XmDROP_CANCEL, XmDROP_HELP, and XmDROP_INTERRUPT.
The value of dropAction can be modified to change
the action actually initiated. The value
XmDROP_INTERRUPT is currently unsupported; if specified,
it will be interpreted as a XmDROP_CANCEL.
Indicates the x-coordinate of the pointer in root
window coordinates. Indicates the y-coordinate of
the pointer in root window coordinates.
A pointer to the following structure is passed to the
XmNoperationChangedCallback callback: typedef struct {
int reason;
XEvent *event;
Time timeStamp;
unsigned char operation;
unsigned char operations;
unsigned char dropSiteStatus; }XmOperationChangedCallbackStruct,
*XmOperationChangedCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the time at
which the crossing event occurred. Identifies an operation.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes operation to the
value of the operation member of the XmDragProcCallbackStruct
at the time the DropSite's XmNdragProc
returns.
If the toolkit has not called an XmNdragProc and
the pointer is within an active drop site, the
toolkit initializes operation by selecting an operation
from the bitwise AND of the initial value of
the operations member and the value of the DropSite's
XmNdropSiteOperations resource. The toolkit
searches this set first for XmDROP_MOVE, then for
XmDROP_COPY, then for XmDROP_LINK, and initializes
operation to the first operation it finds in the
set. If the toolkit finds none of these operations
in the set, it initializes operation to
XmDROP_NOOP.
If the toolkit has not called an XmNdragProc and
the pointer is not within an active drop site, the
toolkit initializes operation by selecting an operation
from the initial value of the operations member.
The toolkit searches this set first for
XmDROP_MOVE, then for XmDROP_COPY, then for
XmDROP_LINK, and initializes operation to the first
operation it finds in the set. If the toolkit finds
none of these operations in the set, it initializes
operation to XmDROP_NOOP. Indicates the set of
operations supported for the source data.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes operations to the
bitwise AND of the DropSite's XmNdropOperations and
the value of the operations member of the XmDragProcCallbackStruct
at the time the DropSite's XmNdragProc
returns. If the resulting set of operations
is empty, the toolkit initializes operations
to XmDROP_NOOP.
If the toolkit has not called an XmNdragProc and
the user does not select an operation (by pressing
a modifier key), the toolkit initializes operations
to the value of the DragContext's XmNdragOperations
resource.
If the toolkit has not called an XmNdragProc and
the user does select an operation, the toolkit initializes
operations to the bitwise AND of the corresponding
operation and the value of the DragContext's
XmNdragOperations resource. If the resulting
set of operations is empty, the toolkit initializes
operations to XmDROP_NOOP. Indicates whether or
not a drop site is valid.
If the toolkit has just called a DropSite's XmNdragProc,
the toolkit initializes dropSiteStatus to
the value of the dropSiteStatus member of the
XmDragProcCallbackStruct at the time the DropSite's
XmNdragProc returns.
If the toolkit has not called an XmNdragProc, it
initializes dropSiteStatus as follows: the toolkit
initializes dropSiteStatus to XmNO_DROP_SITE if the
pointer is over an inactive drop site or is not
over a drop site. The toolkit initializes dropSiteStatus
to XmDROP_SITE_VALID if all the following
conditions are met: The pointer is over an
active drop site The DragContext's XmNexportTargets
and the DropSite's XmNimportTargets are compatible
The initial value of the operation member is not
XmDROP_NOOP
Otherwise, the toolkit initializes dropSiteStatus
to XmDROP_SITE_INVALID.
A pointer to the following structure is passed to callbacks
for XmNtopLevelEnterCallback: typedef struct {
int reason;
XEvent *event;
Time timestamp;
Screen screen;
Window window;
Position x;
Position y;
unsigned char dragProtocolStyle; }XmTopLevelEnterCallbackStruct,
*XmTopLevelEnterCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the timestamp
of the logical event. Specifies the screen associated
with the top-level window or root window being
entered. Specifies the ID of the top-level window or root
window being entered. Indicates the x-coordinate of the
pointer in root window coordinates. Indicates the y-coordinate
of the pointer in root window coordinates. Specifies
the protocol style adopted by the initiator. The
values are XmDRAG_DROP_ONLY, XmDRAG_DYNAMIC, XmDRAG_NONE,
and XmDRAG_PREREGISTER.
A pointer to the following structure is passed to callbacks
for XmNtopLevelLeaveCallback: typedef struct {
int reason;
XEvent *event;
Time timestamp;
Screen screen;
Window window; }XmTopLevelLeaveCallbackStruct, *XmTopLevelLeaveCallback;
Indicates why the callback was invoked. Points to the
XEvent that triggered the callback. Specifies the timestamp
of the logical event. Specifies a screen associated
with the top-level window or root window being left.
Specifies the ID of the top-level window or root window
being left.
Translations [Toc] [Back]
The XmDragContext translations are listed below. These
translations may not directly correspond to a translation
table. BDrag Motion: DragMotion() BDrag Release: FinishDrag()
KCancel: CancelDrag() KHelp: HelpDrag()
Action Routines [Toc] [Back]
The XmDragContext action routines are described below:
Cancels the drag operation and frees the associated DragContext.
Drags the selected data as the pointer is moved.
Finishes the drag operation and starts the drop operation.
Initiates a conditional drop that enables the receiver to
provide help information to the user. The user can cancel
or continue the drop operation in response to this information.
Virtual Bindings [Toc] [Back]
The bindings for virtual keys are vendor specific. For
information about bindings for virtual buttons and keys,
see VirtualBindings(3X).
Core(3X), XmDisplay(3X), XmDragCancel(3X), XmDragIcon(3X),
XmDragStart(3X), XmDropSite(3X), XmDropTransfer(3X),
XmScreen(3X)
XmDragContext(3X)
[ Back ] |
