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