Hi!
I have added ability to set data type and mandatory to the report's variables (develop branch at github).
Also i have extend IDataSourceManager interface.
From now you can get all information about the report's variables:
1. Variable names via report.datamanager.variableNames()
2. Variable data type via report.datamanager.variableDataType(const QString& name)
(enum VariableDataType {Undefined, String, Bool, Int, Real, Date, Time, DateTime})
3. Variable mandatory via report.datamanager.variableIsMandatory(const QString& name)
4. via report.datamanager.variableIsSystem(const QString& name) you can check that the variable is system