Dependency node messages. More...

#include <MNodeMessage.h>

Inheritance diagram for MNodeMessage:

Public Types
enum	AttributeMessage { kConnectionMade = 0x01, kConnectionBroken = 0x02, kAttributeEval = 0x04, kAttributeSet = 0x08, kAttributeLocked = 0x10, kAttributeUnlocked = 0x20, kAttributeAdded = 0x40, kAttributeRemoved = 0x80, kAttributeRenamed = 0x100, kAttributeKeyable = 0x200, kAttributeUnkeyable = 0x400, kIncomingDirection = 0x800, kAttributeArrayAdded = 0x1000, kAttributeArrayRemoved = 0x2000, kOtherPlugSet = 0x4000, kLast = 0x8000 }
	The type of attribute changed/addedOrRemoved messages that has occurred. More...

enum	KeyableChangeMsg { kKeyChangeInvalid = 0, kMakeKeyable, kMakeUnkeyable, kKeyChangeLast }
	Allows you to prevent attributes from becoming (un)keyable. More...

typedef void(*	MAttr2PlugFunction) (MNodeMessage::AttributeMessage msg, MPlug &plug, MPlug &otherPlug, void *clientData)
	Pointer to an AttributeMessage callback which takes two plugs. More...

typedef void(*	MAttrPlugFunction) (MNodeMessage::AttributeMessage msg, MPlug &plug, void *clientData)
	Pointer to an AttributeMessage callback which takes a single plug. More...

typedef void(*	MKeyableFunction) (MPlug &plug, void *clientData, MNodeMessage::KeyableChangeMsg msg, bool &decision)
	Pointer to a change in keyability callback function. More...

Public Types inherited from MMessage
enum	Action { kDefaultAction, kDoNotDoAction, kDoAction }
	Callback result action codes. More...

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...

Static Public Member Functions
static MCallbackId	addAttributeChangedCallback (MObject &node, MNodeMessage::MAttr2PlugFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	This method registers a callback for attribute changed messages. More...

static MCallbackId	addAttributeAddedOrRemovedCallback (MObject &node, MNodeMessage::MAttrPlugFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	Registers callbacks for attribute add/removed messages. More...

static MCallbackId	addNodeDirtyCallback (MObject &node, MMessage::MNodeFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	Registers a callback for node dirty messages. More...

static MCallbackId	addNodeDirtyPlugCallback (MObject &node, MMessage::MNodePlugFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	Registers a callback for node dirty messages. More...

static MCallbackId	addNameChangedCallback (MObject &node, MMessage::MNodeStringFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	Registers a callback for name changed messages. More...

static MCallbackId	addUuidChangedCallback (MObject &node, MMessage::MNodeUuidFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	Registers a callback for UUID changed messages. More...

static MCallbackId	addNodeAboutToDeleteCallback (MObject &node, MMessage::MNodeModifierFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	Registers a callback which will get called when a node is about to be deleted. More...

static MCallbackId	addNodePreRemovalCallback (MObject &node, MMessage::MNodeFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	Registers a callback which will get called before a node is deleted. More...

static MCallbackId	addNodeDestroyedCallback (MObject &node, MMessage::MBasicFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	NodeDestroyed callback. More...

static MCallbackId	addKeyableChangeOverride (MPlug &plug, MNodeMessage::MKeyableFunction func, void clientData=NULL, MStatus status=NULL)
	Attribute keyable state change override. More...

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

static MCallbackId	addNodeDirtyCallback (MObject &node, MMessage::MBasicFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	This method is obsolete. More...

static MCallbackId	addNodeDirtyCallback (MObject &node, MMessage::MNodePlugFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	This method is obsolete. More...

static MCallbackId	addNameChangedCallback (MObject &node, MMessage::MNodeFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	This method is obsolete. More...

static MCallbackId	addNodeAboutToDeleteCallback (MObject &node, MMessage::MModifierFunction func, void clientData=NULL, MStatus ReturnStatus=NULL)
	This method is obsolete. 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

Dependency node messages.

This class is used to register callbacks for dependency node messages of specific dependency nodes.

There are 5 add callback methods which will add callbacks for the following messages

Attribute Changed
Attribute Added or Removed
Node Dirty
Name Changed
UUID Changed

The first parameter passed to each of the add callback methods is the dependency node that will trigger the callback.

Callbacks that are registered for attribute changed/addedOrRemoved messages will be passed an AttributeMessage value as a parameter. This value indicates the type of attribute message that has occurred. See the AttributeMessage enum for all available messages.

Each method returns an id which is used to remove the callback.

To remove a callback use MMessage::removeCallback. All callbacks that are registered by a plug-in must be removed by that plug-in when it is unloaded. Failure to do so will result in a fatal error.

Member Typedef Documentation

typedef void(* MAttr2PlugFunction) (MNodeMessage::AttributeMessage msg, MPlug &plug, MPlug &otherPlug, void *clientData)

Pointer to an AttributeMessage callback which takes two plugs.

Parameters

[in]	msg	Type of message which caused the function to be called.
[in,out]	plug	First plug. Meaning depends upon the specific message which invoked the callback.
[in,out]	otherPlug	Second plug. Meaning depends upon the specific message which invoked the callback.
[in]	clientData	Pointer to user-defined data supplied when the callback was registered.

typedef void(* MAttrPlugFunction) (MNodeMessage::AttributeMessage msg, MPlug &plug, void *clientData)

Pointer to an AttributeMessage callback which takes a single plug.

Parameters

[in]	msg	Type of message which caused the function to be called.
[in,out]	plug	Meaning depends upon the specific message which invoked the callback.
[in]	clientData	Pointer to user-defined data supplied when the callback was registered.

typedef void(* MKeyableFunction) (MPlug &plug, void *clientData, MNodeMessage::KeyableChangeMsg msg, bool &decision)

Pointer to a change in keyability callback function.

Parameters

[in,out]	plug	The plug whose keyability is changing.
[in]	clientData	Pointer to user-defined data supplied when the callback was registered.
[in]	msg	Specifies how the plug's keyability is changing.
[out]	decision	Callback sets this true to accept the change, false to reject it.

Member Enumeration Documentation

enum AttributeMessage

The type of attribute changed/addedOrRemoved messages that has occurred.

Enumerator
kConnectionMade	a connection has been made to an attribute of this node
kConnectionBroken	a connection has been broken for an attribute of this node
kAttributeEval	an attribute of this node has been evaluated
kAttributeSet	an attribute value of this node has been set
kAttributeLocked	an attribute of this node has been locked
kAttributeUnlocked	an attribute of this node has been unlocked
kAttributeAdded	an attribute has been added to this node
kAttributeRemoved	an attribute has been removed from this node
kAttributeRenamed	an attribute of this node has had an alias added, removed, or renamed
kAttributeKeyable	an attribute of this node has been marked keyable
kAttributeUnkeyable	an attribute of this node has been marked unkeyable
kIncomingDirection	the connection was coming into the node
kAttributeArrayAdded	an array attribute has been added to this node
kAttributeArrayRemoved	an array attribute has been removed from this node
kOtherPlugSet	the otherPlug data has been set
kLast	last value of the enum

enum KeyableChangeMsg

Allows you to prevent attributes from becoming (un)keyable.

Enumerator
kKeyChangeInvalid
kMakeKeyable
kMakeUnkeyable
kKeyChangeLast

Member Function Documentation

OPENMAYA_MAJOR_NAMESPACE_OPEN MCallbackId addAttributeChangedCallback	(	MObject &	node,
		MNodeMessage::MAttr2PlugFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This method registers a callback for attribute changed messages.

See the AttributeChanged enum for a list of all possible messages that will trigger the callback.

Note: Attribute Changed messages will not be generated while Maya is either in playback or scrubbing modes. If you need to do something during playback or scrubbing you will have to register a callback for the timeChanged message which is the only message message that is sent during those modes.

The callback function will be passed the type of attribute message that has occurred, the plug(s) for the attributes, and any client data that the user wishes to pass in.

Example callback ( prints out a message when a connection is made or broken ) :

void userCB( MNodeMessage::AttributeMessage msg, MPlug & plug,
             MPlug & otherPlug, void* )
{
    if ( msg & MNodeMessage::kConnectionMade ) {
        cout << "Connection made ";
    } else if ( msg & MNodeMessage::kConnectionBroken ) {
        cout << "Connection broken ";
    } else {
        return;
    }
    cout << plug.info();
    if  ( msg & MNodeMessage::kOtherPlugSet ) {
        if ( msg & MNodeMessage::kIncomingDirection ) {
            cout << "  <--  " << otherPlug.info();
        } else {
            cout << "  -->  " << otherPlug.info();
        }
    }
    cout << endl;
}

Parameters

[in]	node	the node to register the callback for. If this is a NULL MObject then the callback applies to all nodes.
[in]	func	the callback function, which takes the following parameters: msg the kind of attribute change triggering the callback plug the node's plug where the connection changed otherPlug the plug opposite the node's plug where the connection changed clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

Examples:: apiMeshShape/apiMeshShape.cpp, cgFx/cgfxShaderNode.cpp, and nodeMessageCmd/nodeMessageCmd.cpp.

MCallbackId addAttributeAddedOrRemovedCallback	(	MObject &	node,
		MNodeMessage::MAttrPlugFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Registers callbacks for attribute add/removed messages.

This is a more specific version of addAttributeChanged as only attribute added and attribute removed messages will trigger the callback.

Parameters

[in]	node	the node to register the callback for
[in]	func	the callback function, which takes the following parameters: msg the kind of attribute change triggering the callback plug the node's plug where the connection changed clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

Examples:: cgFx/cgfxShaderNode.cpp.

MCallbackId addNodeDirtyCallback	(	MObject &	node,
		MMessage::MNodeFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Registers a callback for node dirty messages.

Parameters

[in]	node	the node to register the callback for
[in]	func	the callback function, which takes the following parameters: node The node that has become dirty clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

MCallbackId addNodeDirtyPlugCallback	(	MObject &	node,
		MMessage::MNodePlugFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Registers a callback for node dirty messages.

This callback provides the plug on the node that was dirtied. Only provides dirty information on input plugs.

Parameters

[in]	node	the node to register the callback for
[in]	func	the callback function, which takes the following parameters: node The node that has become dirty plug The plug on the node that has become dirty clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

Examples:: gpuCache/gpuCacheSubSceneOverride.cpp.

MCallbackId addNameChangedCallback	(	MObject &	node,
		MMessage::MNodeStringFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Registers a callback for name changed messages.

Parameters

[in]	node	the node. If this is a NULL MObject then the callback applies to all node name changes.
[in]	func	the callback function, which takes the following parameters: node the node prevName the previous name of the node clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

MCallbackId addUuidChangedCallback	(	MObject &	node,
		MMessage::MNodeUuidFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Registers a callback for UUID changed messages.

Parameters

[in]	node	the node. If this is a NULL MObject then the callback applies to all node UUID changes.
[in]	func	the callback function, which takes the following parameters: node the node prevUuid the previous UUID of the node clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

MCallbackId addNodeAboutToDeleteCallback	(	MObject &	node,
		MMessage::MNodeModifierFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Registers a callback which will get called when a node is about to be deleted.

The callback will be passed the MDGModifer that will be used to delete the node. This modifier can be used to do any DG modifications, such as disconnections, before the node is deleted. These operations are also stored and performed when the deletion operation is undone or redone.

The callback registered with this method will only get called when the deletion operation is first performed. Undos and redos will be handled solely through the MDGModifier which was passed to the callback on the original deletion. If you also wish to receive notification of deletion events when they are redone, you should register an additional callback using addNodePreRemovalCallback().

When a node is deleted Maya automatically breaks all connections to that node. This process takes place after the callback has been called. This means that if you use the passed-in MDGModifier to break any connections to the node you must be sure to call the modifier's doIt() method before returning from the callback. Otherwise Maya will see that the connections still exist and try to delete them again, which can lead to errors.

The example below shows a callback function which takes the connection coming into the node's input attribute and reconnects it to all of the plugs connected to the node's output attribute:

import maya.OpenMaya as om
def rewire(node, dgmod, data):
    nodefn = om.MFnDependencyNode(node)
    try:
        # Find the input plug.
        inPlug = nodefn.findPlug('input')
        # Get the incoming connections.
        srcs = om.MPlugArray()
        inPlug.connectedTo(srcs, True, False)
        if srcs.length() > 0:
            srcPlug = srcs[0]
            outPlug = nodefn.findPlug('output')
            dests = om.MPlugArray()
            outPlug.connectedTo(dests, False, True)
            if dests.length() > 0:
                # Now that we know we have a valid flow-through
                # connection, disconnect the source from this node.
                dgmod.disconnect(srcPlug, inPlug)
                # Disconnect all of destinations from this node.
                for i in range(dests.length()):
                    dgmod.disconnect(outPlug, dests[i])
                # Force our disconnections to be done now.
                dgmod.doIt()
                # Make a direct connection from the source to each of
                # the destinations.
                for i in range(dests.length()):
                    dgmod.connect(srcPlug, dests[i])
    except:
        # This node does not have an 'input' plug, or does not have
        # an 'output' plug, so let's ignore it.
        pass

Note that it uses the passed-in MDGModifier to perform all the disconnections and connections. This ensures that if the deletion is undone or redone then all of the connections will be restored correctly.

After it is done breaking connections, the callback calls the modifier's doIt() method to commit those disconnections. As noted above, this is necessary to ensure that Maya doesn't see the connections and try to break them again later on.

Parameters

[in]	node	the node to register the callback for
[in]	func	the callback function, which takes the following parameters: node the node that will be deleted modifier DG modifier used to delete the node clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

Examples:: deletedMsgCmd/deletedMsgCmd.cpp.

MCallbackId addNodePreRemovalCallback	(	MObject &	node,
		MMessage::MNodeFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Registers a callback which will get called before a node is deleted.

This callback is called before connections on the node are removed. Unlike the aboutToDelete callback, this callback will be invoked whenever the node is deleted, even during a redo.

Pre-removal and aboutToDelete callbacks serve different purposes. If DG changes need to be made when a node is deleted, the aboutToDelete callback should be used to add undoable operations to an MDGModifier to perform these changes. When the desired actions cannot be accomplished using the MDGModifier passed to the aboutToDelete callback, this callback can be used to receive notification of the deletion event, even during redo.

Note that this callback method should not perform any DG operations.

Parameters

[in]	node	the node to register the callback for
[in]	func	the callback function, which takes the following parameters: node the node that is being deleted clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

Examples:: deletedMsgCmd/deletedMsgCmd.cpp.

MCallbackId addNodeDestroyedCallback	(	MObject &	node,
		MMessage::MBasicFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

NodeDestroyed callback.

Registers a callback which will get called when a node's destructor is called.

Parameters

[in]	node	the node to register the callback for
[in]	func	the callback function, which takes the following parameters: clientData User defined data passed to the callback function
[in]	clientData	User defined data that will be passed to the callback function
[out]	ReturnStatus	status code

Returns: Identifier used for removing the callback.

Status Codes:

MS::kSuccess Operation succeeded
MS::kInsufficientMemory No memory available
MS::kFailure Error adding callback

MCallbackId addKeyableChangeOverride	(	MPlug &	plug,
		MNodeMessage::MKeyableFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

Attribute keyable state change override.

This method registers a callback that is invoked by any class that changes the keyable state of an attribute.

When the callback is invoked, the API programmer can make a decision on how to handle the given keyable change event. The programmer can either accept the the keyable state change by returning a decision == 'true' or reject it by returning decision == 'false'.

Note: you can only attach one callback keyable change override callback per attribute. It is an error to attach more than one callback to the same attribute.

Parameters

[in]	plug	The plug to which to attach the callback.
[in]	func	the callback function, which takes the following parameters: plug - The plug that triggered the callback. clientData - User defined data passed to the callback function. eventType - Description of the event. decision - Return true to accept the keyable state change or false to reject it.
[in]	clientData	User defined data passed back to the user.
[in]	ReturnStatus	status code

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.

MCallbackId addNodeDirtyCallback	(	MObject &	node,
		MMessage::MBasicFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This method is obsolete.

This method is not available in Python.

[as of Maya 2019]

Deprecated:: Use the version which takes a callback function of type MMessage::MNodeFunction instead.

Parameters

[in]	node
[in]	func
[in]	clientData
[out]	ReturnStatus

MCallbackId addNodeDirtyCallback	(	MObject &	node,
		MMessage::MNodePlugFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This method is obsolete.

This method is not available in Python.

[as of Maya 2019]

Deprecated:: Use the MNodeMessage::addNodeDirtyPlugCallback method instead.

Parameters

[in]	node
[in]	func
[in]	clientData
[out]	ReturnStatus

MCallbackId addNameChangedCallback	(	MObject &	node,
		MMessage::MNodeFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This method is obsolete.

This method is not available in Python.

[as of Maya 2019]

Deprecated:: Use the version which takes a callback function of type MMessage::MNodeStringFunction instead.

MCallbackId addNodeAboutToDeleteCallback	(	MObject &	node,
		MMessage::MModifierFunction	func,
		void *	clientData = `NULL`,
		MStatus *	ReturnStatus = `NULL`
	)

static

This method is obsolete.

This method is not available in Python.

[as of Maya 2019]

Deprecated:: Use the version which takes a callback function of type MMessage::MNodeModifierFunction instead.

Parameters

[in]	node
[in]	func
[in]	clientData
[out]	ReturnStatus

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

MNodeMessage.h
MNodeMessage.cpp

Public Types

Static Public Member Functions

Detailed Description

Member Typedef Documentation

Member Enumeration Documentation

Member Function Documentation