Node and plug locking messages. More...

#include <MLockMessage.h>

Inheritance diagram for MLockMessage:

Public Types
typedef void(*	MLockEventFunction) (MObject &node, MObject &aux, void *clientData, MLockMessage::LockEvent eventType, bool &decision)
	Pointer to a dependency node lock event callback function. More...

typedef void(*	MLockDagEventFunction) (MDagPath &dagPath, MDagPath &otherPath, void *clientData, MLockMessage::LockDAGEvent eventType, bool &decision)
	Pointer to a DAG lock event callback function. More...

typedef void(*	MLockPlugEventFunction) (MPlug &plug, MPlug &otherPlug, void *clientData, MLockMessage::LockPlugEvent eventType, bool &decision)
	Pointer to a plug lock event callback function. More...

Public Types inherited from MMessage
typedef void(*	MBasicFunction) (void *clientData)
	Pointer to a basic callback function. More...

typedef void(*	MElapsedTimeFunction) (float elapsedTime, float lastTime, void *clientData)
	Pointer to an elapsed time callback function. More...

typedef void(*	MCheckFunction) (bool retCode, void clientData)
	Pointer to callback function which returns a true/false result. More...

typedef void(*	MCheckFileFunction) (bool retCode, MFileObject &file, void clientData)
	Pointer to a callback function which takes a file object and returns a result. More...

typedef void(*	MCheckPlugFunction) (bool retCode, MPlug &plug, void clientData)
	Pointer to a callback function which takes a plug and returns a result. More...

typedef void(*	MComponentFunction) (MUintArray componentIds[], unsigned int count, void *clientData)
	Pointer to a callback function which takes an array of component ids. More...

typedef void(*	MNodeFunction) (MObject &node, void *clientData)
	Pointer to a callback function which takes a dependency node. More...

typedef void(*	MStringFunction) (const MString &str, void *clientData)
	Pointer to callback function which takes a string. More...

typedef void(*	MTwoStringFunction) (const MString &str1, const MString &str2, void *clientData)
	Pointer to a callback function which takes two strings. More...

typedef void(*	MThreeStringFunction) (const MString &str1, const MString &str2, const MString &str3, void *clientData)
	Pointer to a callback function which takes three strings. More...

typedef void(*	MStringIntBoolIntFunction) (const MString &str, unsigned int index, bool flag, unsigned int type, void *clientData)
	Pointer to callback function which takes a string, an index, a flag and a type. More...

typedef void(*	MStringIndexFunction) (const MString &, unsigned int index, void *clientData)
	Pointer to callback function which takes a string and index. More...

typedef void(*	MNodeStringBoolFunction) (MObject &node, const MString &, bool, void *clientData)
	Pointer to a callback function which takes a node, a string and a boolean. More...

typedef void(*	MStateFunction) (bool state, void *clientData)
	Pointer to a callback function which takes a boolean state. More...

typedef void(*	MTimeFunction) (MTime &time, void *clientData)
	Pointer to callback function which takes a time. More...

typedef void(*	MPlugFunction) (MPlug &srcPlug, MPlug &destPlug, bool made, void *clientData)
	Pointer to plug connection callback function. More...

typedef void(*	MNodePlugFunction) (MObject &node, MPlug &plug, void *clientData)
	Pointer to a callback function which takes a dependency node and a plug. More...

typedef void(*	MNodeStringFunction) (MObject &node, const MString &str, void *clientData)
	Pointer to a callback function which takes a dependency node and a string. More...

typedef void(*	MParentChildFunction) (MDagPath &child, MDagPath &parent, void *clientData)
	Pointer to to a callback function which takes two DAG nodes in a parent/child relationship. More...

typedef void(*	MModifierFunction) (MDGModifier &modifier, void *clientData)
	Pointer to a callback function which takes a DG modifier. More...

typedef void(*	MStringArrayFunction) (const MStringArray &strs, void *clientData)
	Pointer to a callback function which takes a string array. More...

typedef void(*	MNodeModifierFunction) (MObject &node, MDGModifier &modifier, void *clientData)
	Pointer to a callback function which takes a dependency node and a DG modifier. More...

typedef void(*	MObjArray) (MObjectArray &objects, void *clientData)
	Pointer to a callback function which takes an array of objects. More...

typedef void(*	MNodeObjArray) (MObject &node, MObjectArray &objects, void *clientData)
	Pointer to a callback function which takes a dependency node and an array of objects. More...

typedef void(*	MStringNode) (const MString &str, MObject &node, void *clientData)
	Pointer to a callback function which takes a string and a dependency node. More...

typedef void(*	MCameraLayerFunction) (MObject &cameraSetNode, unsigned int multiIndex, bool added, void *clientData)
	Pointer to a callback function which takes a dependency node, an unsigned integer, and a boolean value. More...

typedef void(*	MCameraLayerCameraFunction) (MObject &cameraSetNode, unsigned int multiIndex, MObject &oldCamera, MObject &newCamera, void *clientData)
	Pointer to a callback function which takes a dependency node, an unsigned integer, and two camera transform nodes. More...

typedef void(*	MConnFailFunction) (MPlug &srcPlug, MPlug &destPlug, const MString &srcPlugName, const MString &dstPlugName, void *clientData)
	Pointer to connection-failed callback function. More...

typedef void(*	MPlugsDGModFunction) (MPlugArray &plugs, MDGModifier &modifier, void *clientData)
	Pointer to a callback function which takes an array of MPlugs and an MDGModifier. More...

typedef void(*	MNodeUuidFunction) (MObject &node, const MUuid &uuid, void *clientData)
	Pointer to a callback function which takes a dependency node and a UUID. More...

typedef Action(*	MCheckNodeUuidFunction) (bool doAction, MObject &node, MUuid &uuid, void *clientData)
	Pointer to a callback function which takes a dependency node and a UUID, and returns a result. More...

typedef void(*	MObjectFileFunction) (const MObject &object, const MFileObject &file, void *clientData)
	Pointer to a callback function which takes an object and a file object. More...

typedef void(*	MCheckObjectFileFunction) (bool retCode, const MObject &referenceNode, MFileObject &file, void clientData)
	Pointer to a callback function which takes an object and a file object and returns a result. More...

typedef void(*	MRenderTileFunction) (int originX, int originY, int tileMaxX, int tileMaxY, const void *tileData)
	Pointer to a callback function which receives origin, size and image data. More...

Public Member Functions
	OPENMAYA_ENUM (LockPlugEvent, kInvalidPlug=0, kPlugLockAttr, kPlugUnlockAttr, kPlugAttrValChange, kPlugRemoveAttr, kPlugRenameAttr, kPlugConnect, kPlugDisconnect, kLastPlug)
	Plug related locking events. More...

	OPENMAYA_ENUM (LockDAGEvent, kInvalidDAG=0, kGroup, kUnGroup, kReparent, kChildReorder, kCreateNodeInstance, kCreateChildInstance, kCreateParentInstance, kLastDAG)
	DAG related locking events. More...

	OPENMAYA_ENUM (LockEvent, kInvalid=0, kRename, kDelete, kLockNode, kUnlockNode, kAddAttr, kRemoveAttr, kRenameAttr, kUnlockAttr, kLockAttr, kLast)
	Miscellaneous lock event types. More...

Public Member Functions inherited from MMessage
	OPENMAYA_ENUM (Action, kDefaultAction, kDoNotDoAction, kDoAction)
	Callback result action codes.

Static Public Member Functions
static MCallbackId	setNodeLockQueryCallback (MObject &node, MLockMessage::MLockEventFunction func, void clientData=NULL, MStatus status=NULL)
	This methods registers a callback that is invoked in any locking condition on node properties, e.g. More...

static MCallbackId	setNodeLockDAGQueryCallback (MDagPath &path, MLockMessage::MLockDagEventFunction func, void clientData=NULL, MStatus status=NULL)
	This methods registers a callback that is invoked in any situation involving a locking condition on DAG level changes. More...

static MCallbackId	setPlugLockQueryCallback (MPlug &plug, MLockMessage::MLockPlugEventFunction func, void clientData=NULL, MStatus status=NULL)
	This method registers a callback that is invoked in any locking condition on a plug, e.g. More...

static MCallbackId	setPlugLockQueryCallback (MObject &node, MLockMessage::MLockPlugEventFunction func, void clientData=NULL, MStatus status=NULL)
	This method registers a callback that is invoked in any locking condition on any plug of a given node, e.g. More...

static const char *	className ()
	Returns the name of this class. More...

Static Public Member Functions inherited from MMessage
static MStatus	removeCallback (MCallbackId id)
	Remove the specified callback from maya. More...

static MStatus	removeCallbacks (MCallbackIdArray &ids)
	Remove all of the specified callbacks from maya. More...

static MCallbackId	currentCallbackId (MStatus *ReturnStatus=NULL)
	Return the callback ID of the currently executing callback. More...

static MStatus	nodeCallbacks (MObject &node, MCallbackIdArray &ids)
	Returns a list of callback IDs associated registered to a given node. More...

static void	setRegisteringCallableScript ()
	Mark this MMessage object as one that will be passed callbacks defined in script.

static bool	registeringCallableScript ()
	Return true if this MMessage object has its callbacks defined in script.

static void	stopRegisteringCallableScript ()
	Stop this MMessage object from being passed. More...

static const char *	className ()
	Returns the name of this class. More...

static MStatus	removeCallbacks (MIntArray &ids)
	This method is obsolete. More...

static MStatus	nodeCallbacks (MObject &node, MIntArray &ids)
	This method is obsolete. More...

Detailed Description

Node and plug locking messages.

Plug locking was implemented with Maya 1.0. Individual plugs can be locked so that their values cannot be changed. The locking state is held within the plug. The plug's locked state can be changed via the API with the method MPlug::setLocked(bool), or, in MEL, using the command "setAttr -l {on,off}".

The ability to lock nodes was added with Maya 4.5. Node locking prevents renaming, reparenting, deletion, and other node-related changes. It also restricts the ability to change the state of any plug locks. The intent is that the user relies upon plug locking first, to lock the desired plugs they don't want to change, and then uses node locking to lock the node itself. Node locking can be set via MEL command, "lockNode", or via MFnDependencyNode::setLocked(bool)

MLockMessage class allows the API user to register callbacks that control how Maya handles locks. The registered callbacks are invoked whenever a query to the lock state is involved. Therefore, the callback would be called even if the node was not locked.

When a callback is invoked, the API user will be given a decision variable where they can place their decision. This decision variable is a boolean, and the boolean can take on the following values:

true - accept the default behavior. When the node/plug is locked the default behavior is to obey the lock. When the node/plug is unlocked the default behavior is to do the action/edit.
false - deny the default behavior. When the node/plug is locked the default behavior is to deny/override the lock; thus allowing the edit/action to occur. When the node/plug is unlocked the default behavior is make the node/plug locked - without physically setting the lock bit.

Caveats

You must use caution when using these routines. The flow of execution is interrupted when these callbacks are invoked. Therefore, you should make your decision in a timely maanner or a serious performance penalty will result. Also, you should NEVER try to alter the DG state while executing within callback. This includes quering/assigning a plug's value. You may, however, examine state information like the lock state of the plug/node.

Member Typedef Documentation

typedef void(* MLockEventFunction) (MObject &node, MObject &aux, void *clientData, MLockMessage::LockEvent eventType, bool &decision)

Pointer to a dependency node lock event callback function.

Parameters

[in,out]	node	Node for which the lock event occurred.
[in,out]	aux	Auxiliary data used by some events. E.g. the attribute about to be added.
[in]	clientData	Pointer to user-defined data supplied when the callback was registered.
[in]	eventType	Type of node lock event which occurred.
[out]	decision	Decision of the callback whether to allow (true) or disallow (false) the default action associated with the lock event.

typedef void(* MLockDagEventFunction) (MDagPath &dagPath, MDagPath &otherPath, void *clientData, MLockMessage::LockDAGEvent eventType, bool &decision)

Pointer to a DAG lock event callback function.

Parameters

[in,out]	dagPath	Path to the DAG node for which the lock event occurred.
[in,out]	otherPath	Second DAG node used in some events. E.g. the new parent.
[in]	clientData	Pointer to user-defined data supplied when the callback was registered.
[in]	eventType	Type of DAG node lock event which occurred.
[out]	decision	Decision of the callback whether to allow (true) or disallow (false) the default action associated with the lock event.

typedef void(* MLockPlugEventFunction) (MPlug &plug, MPlug &otherPlug, void *clientData, MLockMessage::LockPlugEvent eventType, bool &decision)

Pointer to a plug lock event callback function.

Parameters

[in,out]	plug	Plug for which the lock event occurred.
[in,out]	otherPlug	Second plug used in some events. E.g. during connect and disconnect events.
[in]	clientData	Pointer to user-defined data supplied when the callback was registered.
[in]	eventType	Type of plug lock event which occurred.
[out]	decision	Decision of the callback whether to allow (true) or disallow (false) the default action associated with the lock event.

Member Function Documentation

OPENMAYA_ENUM	(	LockPlugEvent	,
		kInvalidPlug	= `0`,
		kPlugLockAttr	,
		kPlugUnlockAttr	,
		kPlugAttrValChange	,
		kPlugRemoveAttr	,
		kPlugRenameAttr	,
		kPlugConnect	,
		kPlugDisconnect	,
		kLastPlug
	)

Plug related locking events.

Parameters

kInvalidPlug	An invalid plug event received.
kPlugLockAttr	User is trying to lock the plug.
kPlugUnlockAttr	User is trying to unlock the plug.
kPlugAttrValChange	Plug lock query on plug value change.
kPlugRemoveAttr	Plug lock query on a remove attribute event.
kPlugRenameAttr	Plug lock query on a rename attribute event.
kPlugConnect	Plug lock query on a connect to a locked attribute.
kPlugDisconnect	Plug lock query on a disconnect from a locked source attribute.
kLastPlug	Used for internal bounds checking.

OPENMAYA_ENUM	(	LockDAGEvent	,
		kInvalidDAG	= `0`,
		kGroup	,
		kUnGroup	,
		kReparent	,
		kChildReorder	,
		kCreateNodeInstance	,
		kCreateChildInstance	,
		kCreateParentInstance	,
		kLastDAG
	)

DAG related locking events.

Parameters

kInvalidDAG	Invalid DAG event received.
kGroup	Lock query on group action.
kUnGroup	Lock query on ungroup action.
kReparent	Lock query on reparent action.
kChildReorder	Lock query on a child add action.
kCreateNodeInstance	Lock query on an instance event.
kCreateChildInstance	Lock query on node whose children will be instanced.
kCreateParentInstance	Lock query on node whose parent will be instanced.
kLastDAG	Used for internal bounds checking.

OPENMAYA_ENUM	(	LockEvent	,
		kInvalid	= `0`,
		kRename	,
		kDelete	,
		kLockNode	,
		kUnlockNode	,
		kAddAttr	,
		kRemoveAttr	,
		kRenameAttr	,
		kUnlockAttr	,
		kLockAttr	,
		kLast
	)

Miscellaneous lock event types.

Parameters

kInvalid	Invalid node lock event received.
kRename	Lock query on a rename event.
kDelete	Lock query on a delete event.
kLockNode	Lock query on a lock event.
kUnlockNode	Lock query on an unlock event.
kAddAttr	Lock query on an add attribute event.
kRemoveAttr	Lock query on an remove attribute event.
kRenameAttr	Lock query on an rename attribute event.
kUnlockAttr	Lock query on an unlock attribute event.
kLockAttr	Lock query on a lock attribute event.
kLast	Used for internal bounds checking.

MCallbackId setNodeLockQueryCallback	(	MObject &	node,
		MLockMessage::MLockEventFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This methods registers a callback that is invoked in any locking condition on node properties, e.g.

name, lock status, etc. When called, the API user can make a decision on how to handle the given locking situation. The programmer can either accept the default action, or they can deny the default action. The decision is returned through a decision variable which is passed to the callback function.

The callback function takes the following parameters:

node - The node that triggered the callback.
aux - Any auxiliary data that may be needed, e.g. the attribute about to be added.
clientData - User defined data passed to the callback function.
eventType - Description of the event.
decision - The decision that is made by the registered callback. A value of true accepts the default behavior. A value of false denies the default action.

The meanings of the node and aux parameters for each eventType, and default actions associated with those event types, are as follows:

kRename

node - The node that the user is attempting to rename.
aux - MObject::kNullObj
default actions - If node is locked then the default action is to not allow the rename. Otherwise, if node is unlocked then node can be renamed.

kDelete

node - The node that the user is attempting to delete.
aux - MObject::kNullObj
default actions - If node is locked then the default action is to not allow the delete. If node is unlocked then the node can be deleted.

kLockNode

node - The node that the user is attempting to lock.
aux - MObject::kNullObj
default actions - If node is unlocked then the default action is to ALLOW the node to be locked. The callback is not invoked when the user tries to unlock an already unlocked node.

kUnlockNode

node - The node that the user is attempting to unlock.
aux - MObject::kNullObj
default actions - If node is locked then the default action is to ALLOW the unlock. The callback is not invoked when the user tries to unlock an already unlocked node.

kAddAttr

node - The node that is having an attribute added.
aux - MObject of the attribute to be added. Note: the attribute does not belong to the node yet. You can only access the attribute information using MFnAttribute.
default actions - If node is locked then the default action is to not allow to the addition of aux. If node is unlocked then aux can be added to the node.

kRemoveAttr

node - The node that is having an attribute removed.
aux - The attribute to be removed. In certain situations the user is allowed to do a global delete, e.g. "deleteAttr -at AttrName [nodes]". In these cases the plug is not created until checks have been performed; so aux == MObject::kNullObj.
default actions - If node is locked then the default action is to not allow the attribute removal. If node is unlocked then aux can be removed.

kRenameAttr

node - The node that is having an attribute renamed.
aux - The attribute.
default actions - If node is locked then the default action is to not allow the rename. If node is unlocked then aux can be renamed.

kUnlockAttr

node - The node that is having an attribute unlocked.
aux - The attribute to be unlocked.
default actions - If node is locked then the default action is to not allow the unlock. If node is unlocked then aux attribute can be unlocked.

kLockAttr

node - The node that is having an attribute locked.
aux - The attribute to be locked.
default actions - If node is locked then the default action is to not allow the locking of aux. If node is unlocked then aux can be locked.

Parameters

[in]	node	- The node to register the callback for.
[in]	func	- Pointer to the callback function.
[in]	clientData	- Client data that should be passed back to the callback.
[out]	ReturnStatus	- status code

Returns: A unique id for the callback.

Status Codes:

MS::kFailure - Error registering callback. This can occur when another lock decision callback is already attached to the node.
MS::kInsufficientMemory - Not enough memory to register the callback.
MS::kInvalidParameter - The given node is not a valid node to register the callback on.
MS::kSuccess - Callback successfully added.

OPENMAYA_MAJOR_NAMESPACE_OPEN MCallbackId setNodeLockDAGQueryCallback	(	MDagPath &	dagPath,
		MLockMessage::MLockDagEventFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This methods registers a callback that is invoked in any situation involving a locking condition on DAG level changes.

When called, the API user can make a decision on how to handle the given locking situation. The programmer can either accept the default action, or they can deny the default action. The decision is returned through a decision variable which is passed to the callback function.

The callback function takes the following parameters:

dagPath - The DAG path that the event occurred on.
otherPath - The other path involved, e.g. the new parent.
clientData - User defined data passed to the callback function.
eventType - Description of the event.
decision - The decision that is made by the registered callback. A value of true accepts the default behavior. A value of false rejects the default action.

The meanings of the dagPath and otherPath parameters for each eventType, and default actions associated with those event types, are as follows:

kGroup

dagPath - Path of the node to be grouped.
otherPath - Path of the group node.
default actions - If dagPath is locked then the default action is to not allow the grouping. If dagPath is unlocked then dagPath can be grouped with otherPath.

kUnGroup

dagPath - Path of the node attempted to ungroup.
otherPath - Path of the group node.
default actions - If dagPath is locked then the default action is to not allow the ungrouping. If dagPath is unlocked then dagPath can be ungrouped from otherPath.

kReparent

dagPath - Path of the node which is being reparented.
otherPath - Path of the new parent, if any. When reparenting to the world, otherPath will be invalid.
default actions - If dagPath is locked then the default action is to not allow the reparenting. If dagPath is unlocked then dagPath can be parented to otherPath.

kChildReorder

dagPath - Path of the child node to be reordered.
otherPath - Path of the parent node.
default actions - If dagPath is locked then the default action is to not allow the reordering. If dagPath is unlocked then dagPath can be reordered on otherPath.

kCreateNodeInstance

dagPath - Path of the node which is being instanced.
otherPath - Invalid Path.
default actions - If dagPath is locked then the default action is to not allow the instance to be created. If dagPath is unlocked then dagPath can be instanced.

kCreateChildInstance

dagPath - Path of the node whose child is being instanced.
otherPath - Path of the child node.
default actions - If dagPath is locked then the default action is to not allow the instance to be created. If dagPath is unlocked then dagPath can be instanced.

Parameters

[in]	dagPath	The path to attach the callback.
[in]	func	- Pointer to the callback function.
[in]	clientData	Client data that should be passed back to the callback.
[out]	ReturnStatus	status code

Returns: A unique id for the callback.

Status Codes:

MS::kFailure - Error registering callback. This can occur when another DAG decision callback is already attached to the path.
MS::kInsufficientMemory - Not enough memory to register the callback.
MS::kInvalidParameter - The given path is not a valid path.
MS::kSuccess - Callback successfully added.

MCallbackId setPlugLockQueryCallback	(	MPlug &	plug,
		MLockMessage::MLockPlugEventFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This method registers a callback that is invoked in any locking condition on a plug, e.g.

plug unlock, plug lock, connections, etc. When the callback is invoked, the API programmer can make a decision on how to handle the given locking situation. The programmer can either accept the default action, or they can deny the default action. The decision is made through the decision variable described above.

The callback function takes the following parameters:

plug - The plug that triggered the callback.
otherPlug - The other plug involved in the callback. This is only valid during connect and disconnect events.
clientData - User defined data passed to the callback function.
eventType - Description of the event.
decision - The decision that is made by the registered callback. A value of true accepts the default behavior. A value of false denies the default action.

The meanings of the plug and otherPlug parameters for each eventType, and default actions associated with those event types, are as follows:

kPlugLockAttr

plug - The plug that the user is attempting to lock.
otherPlug - NULL plug.
default actions - If plug is unlocked then the default action is to allow the plug to be locked.

kPlugUnlockAttr

plug - The plug that the user is attempting to unlock.
otherPlug - NULL plug.
default actions - If plug is locked then the default action is to allow the plug to be unlocked.

kPlugAttrValChange

plug - The plug that the user is attempting to change.
otherPlug - NULL plug.
default actions - If plug is locked then the default action is to not allow plug to change. If plug is unlocked then plug can change.

kPlugRemoveAttr

plug - The plug that the user is attempting to remove.
otherPlug - NULL plug.
default actions - If plug is locked then the default action is to not allow removal. Otherwise, if plug is unlocked then plug can be removed.

kPlugRenameAttr

plug - The plug that the user is attempting to rename.
otherPlug - NULL plug.
default actions - If plug is locked then the default action is to not allow the rename. Otherwise, if plug is unlocked then plug can be renamed.

kPlugConnect

plug - The plug that is to be connected (incoming connection).
otherPlug - The source plug of the connection being made.
default actions - If plug is locked then the connection is DENIED. If plug is unlocked then otherPlug can be connected to plug.

kPlugDisconnect

plug - The plug that it is having an incoming connection broken.
otherPlug - The source plug of the connection being made.
default actions - If plug is locked then the default action is to DENY the connection from being broken. If plug is unlocked then otherPlug can be disconnected from plug.

Parameters

[in]	plug	- The plug to attach the callback.
[in]	func	- Pointer to the callback function.
[in]	clientData	- Client data that should be passed back to the callback.
[out]	ReturnStatus	- status code

Returns: A unique id for the callback.

Status Codes:

MS::kFailure - Error registering callback. This can occur when another callback is already attached to the plug. to the plug.
MS::kInsufficientMemory - Not enough memory to register the callback.
MS::kInvalidParameter - The given plug is not a valid plug to register the callback on.
MS::kSuccess - Callback successfully added.

MCallbackId setPlugLockQueryCallback	(	MObject &	node,
		MLockMessage::MLockPlugEventFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This method registers a callback that is invoked in any locking condition on any plug of a given node, e.g.

plug unlock, plug lock, connections, etc. When the callback is invoked, the API programmer can make a decision on how to handle the given locking situation. The programmer can either accept the default action, or they can deny the default action. The decision is returned through a decision variable which is passed to the callback function.

The callback function takes the following parameters:

plug - The plug that triggered the callback.
otherPlug - The other plug involved in the callback. This is only valid during connect and disconnect events.
clientData - User defined data passed to the callback function.
eventType - Description of the event.
decision - The decision that is made by the registered callback. A value of true accepts the default behavior. A value of false denies the default action.

If a lock event occurs on a plug which has callbacks registered both on the plug itself, using the previous method, and on the entire node, using this method, then only the plug-specific callback will be called. This allows you to have both plug-specific and node-wide callbacks on a node while ensuring that the most specific callback is the one called.

The meanings of the plug and otherPlug parameters for each eventType, and the default actions associated with those event types, are described in the plug-specific version of the method, above.

Parameters

[in]	node	- The node to attach the callback.
[in]	func	- Pointer to the callback function.
[in]	clientData	- Client data that should be passed back to the callback.
[out]	ReturnStatus	- status code

Returns: A unique id for the callback.

Status Codes:

MS::kFailure - Error registering callback. This can occur when a global watcher is already attached to the node.
MS::kInsufficientMemory - Not enough memory to register the callback.
MS::kInvalidParameter - The given node is not a valid node to register the callback on.
MS::kSuccess - Callback successfully added.

const char * className ( )

static

Returns the name of this class.

Returns: The name of this class.

The documentation for this class was generated from the following files:

MLockMessage.h
MLockMessage.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Typedef Documentation

Member Function Documentation