Knowledge Base



KB10414 - Display multiple unique symbols on same layer, such as for GPS tracking.

There are three ways to do this:

1) Use the layer property settings (ini files). The point representing each vehicle or other object on the map should have an attribute field with a unique value. Then use the visual layer property settings to associate a unique symbol to point feature(s) with the matching attribute value. The set-up is saved to the TatukGIS project file. (For more on the visual layer property settings and rendering symbols in particular, refer to the relevent TatukGIS Editor/Viewer help topic, tutorials, and video tutorials.)

2) Set/alter INI files programmatically:

 layer.ParamsList.Add;
 layer.Params.Query:='age<18';
 layer.Params.Area.Color:=clRed;
 layer.ParamsList.Add;
 layer.Params.Query:='age>=18';
 layer.Params.Area.Color:=clGreen;

You can also traverse existing ini sections:

for i:=0 to layer.ParamsList.Count -1 do begin
  layer.ParamsList.Selected := i ;
  color := layer.Params.Area.Color ;
  ...
end ;

or
for i:=0 to layer.ParamsList.Count -1 do begin
  color := TGIS_ParamsSectionVector(layer.ParamsList[i]).Area.Color ;
  ...
end ;

3) Alter each shape directly:

  myshp1.Area.Color := clGreen ;
 â€‹myshp2.Area.Color := clRed ;
 myshp3.Area.Color := clYellow ;

 
Created: September 14, 2005, Modified: September 21, 2015