SoEventCallback(3IV)

NAME
SoEventCallback — node which invokes callbacks for events

INHERITS FROM
SoBase > SoFieldContainer > SoNode > SoEventCallback

SYNOPSIS
#include <Inventor/nodes/SoEventCallback.h>

typedef void
SoEventCallbackCB(void *userData, SoEventCallback *node)

Methods from class SoEventCallback:

static SoType
getClassTypeId()

SoEventCallback()
void
setPath(SoPath *path)
const SoPath *
getPath()
void
addEventCallback(SoType eventType, SoEventCallbackCB *f, void *userData = NULL)
void
removeEventCallback(SoType eventType, SoEventCallbackCB *f, void *userData = NULL)
SoHandleEventAction *
getAction() const
const SoEvent *
getEvent() const
const SoPickedPoint *
getPickedPoint() const
void
setHandled()
SbBool
isHandled() const
void
grabEvents()
void
releaseEvents()

Methods from class SoNode:

void
setOverride(SbBool state)
SbBool
isOverride() const
SoNode *
copy(SbBool copyConnections = FALSE) const
virtual SbBool
affectsState() const
static SoNode *
getByName(const SbName &name)
static int
getByName(const SbName &name, SoNodeList &list)

Methods from class SoFieldContainer:

void
setToDefaults()
SbBool
hasDefaultValues() const
SbBool
fieldsAreEqual(const SoFieldContainer *fc) const
void
copyFieldValues(const SoFieldContainer *fc, SbBool copyConnections = FALSE)
SbBool
set(const char *fieldDataString)
void
get(SbString &fieldDataString)
virtual int
getFields(SoFieldList &resultList) const
virtual SoField *
getField(const SbName &fieldName) const
SbBool
getFieldName(const SoField *field, SbName &fieldName) const
SbBool
isNotifyEnabled() const
SbBool
enableNotify(SbBool flag)

Methods from class SoBase:

void
ref()
void
unref() const
void
unrefNoDelete() const
void
touch()
virtual SoType
getTypeId() const
SbBool
isOfType(SoType type) const
virtual void
setName(const SbName &name)
virtual SbName
getName() const

DESCRIPTION
SoEventCallback will invoke application supplied callback functions during SoHandleEventAction traversal. Methods allow the application to specify which Inventor events should trigger callbacks, and which path must be picked, if any, for the callback invocation to occur. The application callback is able to get information about the event and the pick detail, and may grab events, release events, and set whether the event was handled.

If you register more than one callback function in an SoEventCallback node, all the callback functions will be invoked when an event occurs, even if one of the callbacks handles the event. However, if the event is handled by any of the callback functions, no other node in the scene graph will see the event.

METHODS
static SoType
getClassTypeId()
Return the type id for the SoEventCallback class.

SoEventCallback()
Constructor creates an event callback node with no event interest and a NULL path.

void
setPath(SoPath *path)
const SoPath *
getPath()
Set and get the path which must be picked in order for the callbacks to be invoked. If the path is NULL, the callbacks will be invoked for every interesting event, as specified by addEventCallback(), regardless of what is picked. The setPath() method makes its own copy of the passed path.

void
addEventCallback(SoType eventType, SoEventCallbackCB *f, void *userData = NULL)
void
removeEventCallback(SoType eventType, SoEventCallbackCB *f, void *userData = NULL)
Specifies the callback functions to be invoked for different event types. When invoked, the callback function will be passed the userData, along with a pointer to this SoEventCallback node. For example, passing SoMouseButtonEvent::getClassTypeId() means callbacks will be invoked only when a mouse button is pressed or released. Passing SoEvent::getClassTypeId() for the eventType will cause the callback to be invoked for every event which passes through this event callback node.

SoHandleEventAction *
getAction() const
Returns the SoHandleEventAction currently traversing this node, or NULL if traversal is not taking place. This should be called only from callback functions.

const SoEvent *
getEvent() const
Returns the event currently being handled, or NULL if traversal is not taking place. This should be called only from callback functions.

const SoPickedPoint *
getPickedPoint() const
Returns pick information during SoHandleEventAction traversal, or NULL if traversal is not taking place. This should be called only from callback functions.

void
setHandled()
Tells the node the event was handled. The callback function is responsible for setting whether the event was handled or not. If there is more than one callback function registered with an SoEventCallback node, all of them will be invoked, regardless of whether one has handled the event or not. This should be called only from callback functions.

SbBool
isHandled() const
Returns whether the event has been handled. This should be called only from callback functions.

void
grabEvents()
void
releaseEvents()
Tells the event callback node to grab events or release the grab. While grabbing, the node will consume all events; however, each callback function will only be invoked for events of interest.

FILE FORMAT/DEFAULTS
EventCallback {
}

SEE ALSO
SoInteraction, SoSelection, SoHandleEventAction, SoDragger