I have a polygon layer with a numeric attribute (id_ast) which I want to populate with the next consecutive value for every new polygon created in the Map Viewer. When updating polygons this attribute should not be recalculated.
To get this I configured a form and added the following calculated expression to populate id_ast attribute:
if($editcontext.editType == "UPDATE") {
return $feature.id_assentament
} else {
var vals = FeatureSetById($datastore,"0",['id_ast'],false)
var numarray = []
for (var n in vals){
var nn = Number(n.id_ast)
Push(numarray, nn)
}
var maxnum = Max(numarray)
var newnum = maxnum + 1
if(newnum == null) { return 1 }
return newnum
}
If works except when multiple polygons are created in the same edit session. I mean, I select the polygon layer in the Create features section of the Editor pane, then I draw a polygon and before clicking Create I draw more polygons. All this polygons get the same value for id_ast.
How can I access the attribute values of the polygons in the edit session to assign a different id_ast to each?
