The erase(), open(), close(), and cancel() functions all have corresponding virtual functions beginning with the prefix sub. You can override these subsidiary functions to provide extra functionality for derived classes. The subsidiary function is invoked by the nonvirtual “master” function. For example, erase() calls subErase(). The signature for subErase() is as follows:
virtual Acad::ErrorStatus subErase(Adesk::Boolean pErasing);
It is best not to change any state in a subsidiary function. If you must change state, then try to change it after invoking the parent class implementation of the same function (in case an error code is returned). If you must change state before invoking the parent class function, then be prepared to reverse it if the parent class returns a bad status.
The following example shows the implementation of the subErase() function that is called when an object is erased. The subErase() function checks for hard pointer references to other objects and erases them as well.
class AsdkEllipse : public AcDbEllipse
// This class extends AcDbEllipse by adding in functionality
// to store a dynamic array of hard pointer object IDs.
//
// The subErase() member function has been overridden and
// implemented, so when an object of this class is
// erased, the objects pointed to by the hard pointer IDs
// stored within the object will also be erased.
//
{
public:
ACRX_DECLARE_MEMBERS(AsdkEllipse);
AsdkEllipse() {};
AsdkEllipse(const AcDbObjectIdArray& ellipses)
: mEllipseIds(ellipses) {};
AsdkEllipse(const AcGePoint3d& center,
const AcGeVector3d& unitNormal,
const AcGeVector3d& majorAxis,
double radiusRatio,
double startAngle = 0.0,
double endAngle = 6.28318530717958647692);
AsdkEllipse(const AcDbObjectIdArray& ellipses,
const AcGePoint3d& center,
const AcGeVector3d& unitNormal,
const AcGeVector3d& majorAxis,
double radiusRatio,
double startAngle = 0.0,
double endAngle = 6.28318530717958647692);
AcDbObjectId ellipseId(unsigned short which);
Acad::ErrorStatus setEllipseId(
const AcDbObjectId& objId, unsigned short which);
Acad::ErrorStatus setEllipseIds(
const AcDbObjectIdArray& Ids);
Acad::ErrorStatus appendId(const AcDbObjectId& objId);
Acad::ErrorStatus appendIds(
const AcDbObjectIdArray& objIds);
inline Adesk::Boolean removeId(
const AcDbObjectId& objId);
// AcDbObject overrides.
//
virtual Acad::ErrorStatus subErase(
Adesk::Boolean pErasing);
virtual Acad::ErrorStatus dwgInFields(
AcDbDwgFiler* filer);
virtual Acad::ErrorStatus dwgOutFields(
AcDbDwgFiler* filer) const;
virtual Acad::ErrorStatus dxfInFields(
AcDbDxfFiler* filer);
virtual Acad::ErrorStatus dxfOutFields(
AcDbDxfFiler* filer) const;
virtual Acad::ErrorStatus wblockClone(
AcRxObject* pOwnerObject,
AcDbObject*& pClonedObject,
AcDbIdMapping& idMap,
Adesk::Boolean isPrimary = Adesk::kTrue) const;
// AcDbEntity overrides.
//
virtual void list() const;
private:
AcDbObjectIdArray mEllipseIds;
static int mInFlux; // == 1 when first object's
// subErase is erasing.
};
ACRX_DXF_DEFINE_MEMBERS(AsdkEllipse, AcDbEllipse,
AcDb::kDHL_CURRENT, AcDb::kMReleaseCurrent,
0,\
ASDKELLIPSE, REFERENC);
// Static class data member definition.
//
int AsdkEllipse::mInFlux = Adesk::kFalse;
AsdkEllipse::AsdkEllipse(const AcGePoint3d& center,
const AcGeVector3d& unitNormal,
const AcGeVector3d& majorAxis,
double radiusRatio,
double startAngle,
double endAngle) :
AcDbEllipse(center, unitNormal, majorAxis, radiusRatio,
startAngle, endAngle)
{ }
AsdkEllipse::AsdkEllipse(const AcDbObjectIdArray& ellipses,
const AcGePoint3d& center,
const AcGeVector3d& unitNormal,
const AcGeVector3d& majorAxis,
double radiusRatio,
double startAngle,
double endAngle) :
AcDbEllipse(center, unitNormal, majorAxis, radiusRatio,
startAngle, endAngle), mEllipseIds(ellipses)
{ }
AcDbObjectId
AsdkEllipse::ellipseId(unsigned short which)
{
assertReadEnabled();
if (which > mEllipseIds.length())
return AcDbObjectId::kNull;
return mEllipseIds[which];
}
Acad::ErrorStatus
AsdkEllipse::setEllipseId(const AcDbObjectId& objId,
unsigned short which)
{
assertWriteEnabled();
if (which > mEllipseIds.length())
return Acad::eInvalidIndex;
mEllipseIds[which] = objId;
return Acad::eOk;
}
Acad::ErrorStatus
AsdkEllipse::setEllipseIds(const AcDbObjectIdArray& objIds)
{
assertWriteEnabled();
if (objIds.length() == 0)
return Acad::eNullObjectId;
mEllipseIds = objIds;
return Acad::eOk;
}
Acad::ErrorStatus
AsdkEllipse::appendId(const AcDbObjectId& objId)
{
assertWriteEnabled();
if (objId == AcDbObjectId::kNull)
return Acad::eNullObjectId;
mEllipseIds.append(objId);
return Acad::eOk;
}
Acad::ErrorStatus
AsdkEllipse::appendIds(const AcDbObjectIdArray& objIds)
{
assertWriteEnabled();
if (objIds.length() == 0)
return Acad::eNullObjectId;
mEllipseIds.append(objIds);
return Acad::eOk;
}
inline Adesk::Boolean
AsdkEllipse::removeId(const AcDbObjectId& objId)
{
assertWriteEnabled();
return mEllipseIds.remove(objId);
}
// This implementation of subErase opens and erases all
// objects that this entity has hard pointer references
// to. The effect is that when one AsdkEllipse is erased,
// all the others it has hard pointers to also erase as
// a "group".
//
Acad::ErrorStatus
AsdkEllipse::subErase(Adesk::Boolean pErasing)
{
Acad::ErrorStatus es = AcDbEllipse::subErase(pErasing);
if (es != Acad::eOk)
return es;
if (mInFlux == Adesk::kFalse) {
mInFlux = Adesk::kTrue;
AsdkEllipse *pEllipse;
int es;
for (int i = 0; i < mEllipseIds.length(); i++) {
es = acdbOpenObject(pEllipse, mEllipseIds[i],
AcDb::kForWrite, Adesk::kTrue);
if (es != Acad::eOk)
continue;
pEllipse->erase(pErasing);
pEllipse->close();
}
mInFlux = Adesk::kFalse;
}
return Acad::eOk;
}
Acad::ErrorStatus
AsdkEllipse::dwgInFields(AcDbDwgFiler* filer)
{
assertWriteEnabled();
AcDbEllipse::dwgInFields(filer);
mEllipseIds.setLogicalLength(0);
int idCount;
filer->readInt32((long*)&idCount);
AcDbHardPointerId objId;
for (int i = 0; i < idCount; i++) {
filer->readItem(&objId);
mEllipseIds.append(objId);
}
return filer->filerStatus();
}
Acad::ErrorStatus
AsdkEllipse::dwgOutFields(AcDbDwgFiler* filer) const
{
assertReadEnabled();
AcDbEllipse::dwgOutFields(filer);
filer->writeInt32(mEllipseIds.length());
for (int i = 0; i < mEllipseIds.length(); i++) {
filer->writeHardPointerId(mEllipseIds[i]);
}
return filer->filerStatus();
}
Acad::ErrorStatus
AsdkEllipse::dxfInFields(AcDbDxfFiler* filer)
{
assertWriteEnabled();
Acad::ErrorStatus es = AcDbEllipse::dxfInFields(filer);
if (es != Acad::eOk) {
return es;
}
// Check to see if we're at the right subclass data
// marker.
//
if (!filer->atSubclassData("AsdkEllipse")) {
return Acad::eBadDxfSequence;
}
struct resbuf inbuf;
AcDbObjectId objId;
int idCount;
filer->readItem(&inbuf);
if (inbuf.restype == AcDb::kDxfInt32) {
idCount = inbuf.resval.rint;
} else {
filer->pushBackItem();
filer->setError(Acad::eInvalidDxfCode,
"\nError: expected group code %d",
AcDb::kDxfInt32);
return filer->filerStatus();
}
for (int i = 0; i < idCount; i++) {
es = filer->readItem(&inbuf);
if (es != Acad::eOk) {
filer->setError(Acad::eMissingDxfField,
"\nError: expected more group code %d's",
AcDb::kDxfHardPointerId);
return filer->filerStatus();
}
if (inbuf.restype == AcDb::kDxfHardPointerId) {
acdbGetObjectId(objId, inbuf.resval.rlname);
mEllipseIds.append(objId);
} else {
filer->pushBackItem();
filer->setError(Acad::eInvalidDxfCode,
"\nError: expected group code %d",
AcDb::kDxfHardPointerId);
return filer->filerStatus();
}
}
return filer->filerStatus();
}
Acad::ErrorStatus
AsdkEllipse::dxfOutFields(AcDbDxfFiler* filer) const
{
assertReadEnabled();
AcDbEllipse::dxfOutFields(filer);
filer->writeItem(AcDb::kDxfSubclass, "AsdkEllipse");
filer->writeInt32(AcDb::kDxfInt32,
mEllipseIds.length());
for (int i = 0; i < mEllipseIds.length(); i++) {
filer->writeObjectId(AcDb::kDxfHardPointerId,
mEllipseIds[i]);
}
return filer->filerStatus();
}
void
AsdkEllipse::list() const
{
assertReadEnabled();
AcDbEllipse::list();
acutPrintf("\nClass:\t%s", isA()->name());
for (int i = 0; i < mEllipseIds.length(); i++) {
acutPrintf("\nReferenceId[%d]:\t%ld", i,
(mEllipseIds[i]).asOldId());
}
}
Acad::ErrorStatus
AsdkEllipse::wblockClone(AcRxObject* pOwnerObject,
AcDbObject*& pClonedObject,
AcDbIdMapping& idMap,
Adesk::Boolean isPrimary) const
{
assertReadEnabled();
static AcDbObjectId btr, pspace = AcDbObjectId::kNull;
AcTransaction *pTrans = NULL;
pClonedObject = NULL;
if (pspace == AcDbObjectId::kNull) {
AcDbBlockTable *pTable;
database()->getSymbolTable(pTable, AcDb::kForRead);
pTable->getAt(ACDB_PAPER_SPACE, pspace);
pTable->close();
}
if ( idMap.deepCloneContext() == AcDb::kDcXrefBind
&& ownerId() == pspace)
return Acad::eOk;
// Have we already done this entity ?
//
AcDbIdPair idPair(objectId(), (AcDbObjectId)NULL,
Adesk::kTrue);
if (idMap.compute(idPair) == TRUE && idPair.value()
!= NULL)
{
pClonedObject = NULL;
return Acad::eOk;
}
AcDbBlockTableRecord *pBTR
= AcDbBlockTableRecord::cast(pOwnerObject);
if (pBTR != NULL) {
if (isPrimary == Adesk::kTrue)
btr = pBTR->objectId();
else
btr = AcDbObjectId::kNull;
} else if (btr != AcDbObjectId::kNull) {
pTrans = actrTransactionManager->startTransaction();
pTrans->getObject((AcDbObject*&)pBTR, btr,
AcDb::kForWrite);
pOwnerObject = pBTR;
}
Acad::ErrorStatus es
= AcDbEllipse::wblockClone(pOwnerObject,
pClonedObject, idMap, btr != AcDbObjectId::kNull);
if (pTrans)
actrTransactionManager->endTransaction();
acutPrintf("\nWblockClone error status: %s", acadErrorStatusText(es) );
return Acad::eOk;
}
void
createEllipses()
{
const ellipseCount = 10;
AsdkEllipse *pEllipse;
pEllipse = new AsdkEllipse(AcGePoint3d(4.0, 4.0, 0.0),
AcGeVector3d(0.0, 0.0, 1.0),
AcGeVector3d(2.0, 0.0, 0.0),
0.5);
AcDbVoidPtrArray ellipses;
ellipses.append(pEllipse);
// Now use the getTransformedCopy() function with a
// scaling matrix (in X & Y only) to create new
// AsdkEllipses, each 0.5 units larger than the last in
// the X & Y direction, but identical in the Z
// direction. This would be similar to the
// getOffsetCurves() function, but that function
// returns AcDbSpline entities instead of AcDbEllipses.
//
double j = 1.1;
AcGeMatrix3d scale;
for (int i = 0; i < ellipseCount; i++, j += 0.1) {
scale.setToScaling(j, pEllipse->center());
scale.entry[2][2] = 1.0; // Z scaling == 1
// getTransformed copy uses this->clone() to create
// a new object, which the ent pointer is assigned
// to point to. Therefore, ent should NOT point to an
// existing entity or there will be a memory leak!
//
// Since this->clone() is used, the AsdkEllipse class
// must override this member function to
// be sure that an AsdkEllipse is created instead
// of just an AcDbEllipse.
//
AsdkEllipse *pNextEllipse;
((AsdkEllipse*)ellipses[0])->getTransformedCopy(
scale, (AcDbEntity*&)pNextEllipse);
ellipses.append(pNextEllipse);
}
AcDbBlockTable *pBlockTable;
acdbHostApplicationServices()->workingDatabase()
->getSymbolTable(pBlockTable, AcDb::kForRead);
AcDbBlockTableRecord *pBlockTableRecord;
pBlockTable->getAt(ACDB_MODEL_SPACE, pBlockTableRecord,
AcDb::kForWrite);
pBlockTable->close();
AcDbObjectIdArray ellipseIds;
AcDbObjectId tempId;
for (i = 0; i < ellipses.length(); i++) {
pBlockTableRecord->appendAcDbEntity(tempId,
(AsdkEllipse*)ellipses[i]);
ellipseIds.append(tempId);
}
pBlockTableRecord->close();
// Set up the hard pointers and close the ellipses.
//
for (i = 0; i < ellipses.length(); i++) {
// Add in all the IDs.
//
((AsdkEllipse*)ellipses[i])
->setEllipseIds(ellipseIds);
// Now remove the object ID of the "*this" ellipse
// so it doesn't reference itself.
//
((AsdkEllipse*)ellipses[i])->removeId(
((AsdkEllipse*)ellipses[i])->objectId());
((AsdkEllipse*)ellipses[i])->close();
}
}
void
initApp()
{
acedRegCmds->addCommand("ASDK_ELLIPSES",
"ASDK_ELLIPSES", "ELLIPSES",
ACRX_CMD_MODAL, createEllipses);
AsdkEllipse::rxInit();
acrxBuildClassHierarchy();
}
void
unloadApp()
{
acedRegCmds->removeGroup("ASDK_ELLIPSES");
// Remove the AsdkEllipse class from the ACRX runtime
// class hierarchy. If this is done while the database is
// still active, it should cause all objects of class
// AsdkEllipse to be turned into proxies.
//
deleteAcRxClass(AsdkEllipse::desc());
}
extern "C" AcRx::AppRetCode
acrxEntryPoint(AcRx::AppMsgCode msg, void* appId)
{
switch (msg) {
case AcRx::kInitAppMsg:
acrxDynamicLinker->unlockApplication(appId);
acrxDynamicLinker->registerAppMDIAware(appId);
initApp();
break;
case AcRx::kUnloadAppMsg:
unloadApp();
}
return AcRx::kRetOK;
}