| 6.4. Multiple User Actions | ||
|---|---|---|
 | Chapter 6. User Actions |  |
| 6.4. Multiple User Actions | ||
|---|---|---|
| | Chapter 6. User Actions | |
Starting from Geant4 Version 10.3 it is possible to attach multiple
instances of the same type of user action to a single run manager. This is
achieved via the use of a special proxy classes to which multiple
child user actions are attached. This is allowed for run-, event-,
tracking- and stepping-type user actions (G4UserRunAction, G4UserEventAction,G4UserTrackingAction,G4UserSteppingAction).
The kernel still sees a single user action of each type, the proxy will forward the calls from kernel to all the attached child user actions.
Example 6.16. An example of the use of the use of multiple user-actions.
#include "G4MultiRunAction.hh"
#include "G4MultiEventAction.hh"
#include "G4MultiTrackingAction.hh"
#include "G4MultiSteppingAction.hh"
//...
void MyUserActionInitialization::Build()
{
//...
// Example with multiple-event action, similartly
// for the other cases
// multi- user actions extend std::vector
auto multiAction = new G4MultiEventAction { new MyEventAction1, new MyEventAction2 } ;
//...
multiAction->push_back( new MyEventAction3 );
SetUserAction( multiAction );
//...
}
This functionality is not implemented for the the stacking user action
and primary
generation action. There is no multiple
G4UserStackingAction equivalent since this would
require a complex handling of the case in which conflicting
classifications are issued. For the case of
G4VUserPrimaryGeneratorAction the use case
of the multiple user actions is already addressed by the design of the
class itself. User can implement one or more generators in the actions.
For the case of G4MultiRunAction only one of the
child user actions can implement the
G4UserRunAction::GenerateRun() method returning a
non null,
user derived G4Run object, otherwise an
exception is thrown.
| |  | |
| 6.3. User Information Classes |  | Chapter 7. Communication and Control |