Mappoint has a number of methods that require ArrayOfFields: These Include:

ImportData
LinkData
ImportTerritories
LinkTerritories
SetFieldsVisibleInBalloon

My problem is I don't seem to be able to create the Variant array properly
Has anyone had any experience with this problem?

Hi Garry,

After our emails, I remembered a program I wrote that did work with fields. I've had a look at it, and it only queries the fields of existing pushpins. I don't use ArrayOfFields, but if you think it would help I could post it. (I use the getItem method on a Fields object)

Could the polyline/polygon variant code be modified so that they pass "an array of Field" objects rather than "array of Location" objects?


Richard

Alas - that is precisely where I started - I've been trying to use the SafeArray code but I get nowhere.

I have managed to get SetFieldsVisibleInBalloon working using C++.

Deriving some code from Richard Marsden proved to be the solution.

FieldsPtr pFields = pDataSet->Fields;
long i;
int count = pFields->Count;
FieldPtr pField;
Variant index = 0; // CBuilder variant
HRESULT hr;

VARIANT v;
SAFEARRAY FAR* psa;
SAFEARRAYBOUND saBound;

saBound.cElements = count;
saBound.lLbound = 0;
psa = SafeArrayCreate( VT_DISPATCH, 1, &saBound );

VariantInit( &v );
V_VT( &v ) = VT_ARRAY + VT_DISPATCH;
V_ARRAY( &v ) = psa;

for ( i = 0; i < count; i++ )
{
index = i + 1;
pField = pFields->get_Item( index );
hr = SafeArrayPutElement( psa, &i, pField );
}

pDataSet->SetFieldsVisibleInBalloon( v );

I realize this is from July '02, but I am trying to use this code and getting stuck with

Code:

 
Variant index = 0; // CBuilder variant

I am using Visual C++. I really just want one Field passed to the DisplayDataMap method for the second parameter, I don't really need an array of fields.

Here's my code below.

See the second parameter, this is where I get hung up.

It says it will default to the first valid field, so I put the column I want to map as the first field.

How can I simply specify the default for the DataField parameter?

Thanks,
Eric

Code:

 
oDSPtr->DisplayDataMap(MapPoint::geoDataMapTypeMultipleSymbol, NULL, MapPoint::geoShowByDefault,
MapPoint::geoCombineByNone, MapPoint::geoRangeTypeUniqueValues, 
MapPoint::geoRangeOrderDefault, MapPoint::geoColorSchemeDefault, 5);
 
// [ArrayOfCustomValues], [ArrayOfCustomNames], [DivideByField], [ArrayOfDataFieldLabels], [ArrayOfPushpinSymbols]);

Hi,
perhaps it helps You:

//from my program
.....

Code:

void CMapPage::ShowParkPoints()
{
try
{
if(m_bShowPark)
{
m_dsParkPoints = m_DataSets.ImportData(m_strParkPointsPath, NULL, 
geoCountryDefault, geoDelimiterDefault, NULL);
m_dsParkPoints.SetSymbol(20);
int nRecordCount = m_dsParkPoints.GetRecordCount ();
if(nRecordCount == 0)
{
//AfxMessageBox (_T("There are no \"Park\" points"), MB_ICONINFORMATION);
return;
}
COleSafeArray saFields;
saFields.CreateOneDim (VT_DISPATCH, 4);
long lIndex[1];
CFields colFields = m_dsParkPoints.GetFields ();
CField objField;
for(int i = 0; i < 4; i ++)
{
lIndex[0] = i;
objField = colFields.GetItem(COleVariant((long) (i + 2)));
saFields.PutElement (lIndex, objField.m_lpDispatch);
}
m_dsParkPoints.SetFieldsVisibleInBalloon (saFields);
m_DataSets.ZoomTo ();
}
else
m_dsParkPoints.Delete();
} //try
catch (COleDispatchException * pExpn)
{
#ifdef _DEBUG
pExpn->ReportError ();
#endif
pExpn->Delete ();
}
}

......

Thank you Dr.!

Hi Dr. Nobody!

I'm still having the same problems. Have you suceeded in adding the fieldlist to ImportData?

Pit

Originally Posted by DrNobody

Hi,
perhaps it helps You:

//from my program
.....

Code:

void CMapPage::ShowParkPoints()
{
try
{
if(m_bShowPark)
{
m_dsParkPoints = m_DataSets.ImportData(m_strParkPointsPath, NULL, 
geoCountryDefault, geoDelimiterDefault, NULL);
m_dsParkPoints.SetSymbol(20);
int nRecordCount = m_dsParkPoints.GetRecordCount ();
if(nRecordCount == 0)
{
//AfxMessageBox (_T("There are no \"Park\" points"), MB_ICONINFORMATION);
return;
}
COleSafeArray saFields;
saFields.CreateOneDim (VT_DISPATCH, 4);
long lIndex[1];
CFields colFields = m_dsParkPoints.GetFields ();
CField objField;
for(int i = 0; i < 4; i ++)
{
lIndex[0] = i;
objField = colFields.GetItem(COleVariant((long) (i + 2)));
saFields.PutElement (lIndex, objField.m_lpDispatch);
}
m_dsParkPoints.SetFieldsVisibleInBalloon (saFields);
m_DataSets.ZoomTo ();
}
else
m_dsParkPoints.Delete();
} //try
catch (COleDispatchException * pExpn)
{
#ifdef _DEBUG
pExpn->ReportError ();
#endif
pExpn->Delete ();
}
}

......