CallSub non può funzionare perchè l'activity ricevente non è attiva.
CallSubDelay sarebbe la strada da seguire perchè questa forma prima attiva l'activity ricevente e poi effettua la chiamata
Un esempio lo trovi
qui.
Edit: ti riporto la definizione di CallSub, per maggior chiarezza:
Calls the given sub. CallSub can be used to call a sub which belongs to a different module.
However the
sub will only be called if the other module is not paused. In that case an empty string will be returned.
You can use IsPaused to test whether a module is paused.
This means that
one activity cannot call a sub of a different activity. As the other activity will be paused for sure.
CallSub allows an activity to call a service sub or a service to call an activity sub.
Note that it is not possible to call subs of code modules.
CallSub can also be used to call subs in the current module. Pass Me as the component in that case.