Dear Stefano
Please try to build and learn $ROOTSYS/test/Aclock.cxx class.
It is a good example of how TTImer class can be used.
I wonder you can use the approach this class employs.
With my regards,
Valeri
----- Original Message -----
From: Stefano Argiro` <argiro@to.infn.it>
To: <roottalk@pcroot.cern.ch>
Sent: 13 марта 2001 г. 3:47
Subject: [ROOT] questions on TApplication's and TTimer's
>
> Hi,
>
> I would like to use a TTimer in a DAQ that has to read data every
> 20 seconds. For this purpose I have implemented a class called,
> say, Readout:public TObject{} with methods, Start() , Stop(),
> ForceReadout() and overriding HandleTimer().
>
> Class Readout has a TApplication as a data member, and upon Start()
> TApplication::Run() is called.
> Soon I realized that, after calling Start(), the event loop is started,
> and I cannot communicate anymore with the class: I cannot tell it to
> Stop() not to ForceReadout().
>
> Is there a solution to this ? Will the signal/slot mechanism do it
> (right now we are still using v2.25) ?
>
> Thanks
>
> I enclose an outline of the code.
>
> ////////////////////////////////////////////
> class Readout:public TObject{
> private:
> TApplication ftheApplication;
> Int_t fEvents; // number of events
> ...
>
> public:
> Readout();
> void ForceReadout()
> Bool_t HandleTimer(TTimer *timer);
> void Start();
> void Stop();
> Int_t GetEvents() {return fEvents;};
>
> };
>
> Readout::Readout(){
>
> ftheApplication = new TApplication("",&arc,argv,NULL,0);
> ...
> }
>
> void Readout::ForceReadout(){
>
> // do the readout ...
>
> }
>
> void Readout::HandleTimer(TTimer *timer){
> // do the readout , save etc....
> }
>
> void Readout::Start(){
> TTimer * timer = new TTimer(this,20000);
> timer->TurnOn();
> ftheApplication->Run();
>
> return 0;
> }
>
> Int_t CurrentMonitorRO::Stop(){
>
> ftheApplication->Terminate();
> return 0;
> }
> //////////////////////////////////////////////////////////////////
>
> int main(){
>
> TROOT CMReadout("CMreadout","CM readout application");
>
> Readout * readout = new CurrentMonitorRO();
>
> readout->Start();
>
> // of course it never gets here !!
> if (readout->GetEvents() == 5) cout << "Done"<<endl;
> return 0;
>
> }
>
>
>
This archive was generated by hypermail 2b29 : Tue Jan 01 2002 - 17:50:39 MET