KB10220 - I am using the DK with C++Builder and experienced a problem with the Locate functionality. The compiler rejects the following code as invalid:

TGIS_Shape *shp = new TGIS_Shape();

with the errors:

E2352 Cannot create instance of abstract class 'TGIS_Shape'
E2353 Class 'TGIS_Shape' is abstract because of '_fastcall TGIS_Shape::getSmartSize() = 0'

(this is used in the MouseMove and MouseDown procedures)

The Locate function does not create a shp!

shp := TGIS_Shape(GIS.Locate(ptg, 5/GIS.Zoom)); // 5 pixels precision

So your code should look like:

TGIS_Shape *shp := (TGIS_Shape)(GIS.Locate(ptg, 5/GIS.Zoom)); // 5 pixels precision

In any future work please create a known type of object. For example:

TGIS_Shape *shp = new TGIS_ShapeArc();