asked on

Class-member-function as TimerProc

Hi,

I can't figure out how to set a timer so
that it calls a member-function of my
class.

class SomeClass
{
public:
void CALLBACK EXPORT MyTimerProc(HWND hWnd, UINT nMsg, UINT nIDEvent, DWORD dwTime);
void SomeFunction();
}

void SomeClass::SomeFunction()
{
SetTimer(...,MyTimerProc); // << error C2664
}

Currently all I can do is to use a
global, - non-class-member-function
but I need to have access to my class'es
variables when the timer-event occurs.

My problem is that when I try to use
a class-member-function in my SetTimer-
call then the compiler (VC 5.0) refuses
with:
error C2664:
'SetTimer' : cannot convert parameter 4 from 'void (struct HWND__ *,unsigned int,unsigned int,unsigned long)' to 'void (__stdcall *)(struct HWND__ *,unsigned int,unsigned int,unsigned long)'

Basically I want to stay "within" my
class with the TimerProc. Seemingly
I need a cast of some sort.

How can I do that ? Any help greatly appreciated ! Thanks a lot !
Richard

ASKER CERTIFIED SOLUTION

ufolk123

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rhoepperger

ASKER

Thanks a lot. Good solution.
But I just came up with another solution:

MMRESULT mmres=timeSetEvent(1000, 100, TimeProc, (DWORD) this, TIME_PERIODIC);

Multimedia-Timers accept a user-argument
and a point to my this will do the job
for me I guess.

Thanks for your help !
Get the points and the A :))
Enjoy

ufolk123

Yes , it will work
Only thing here is that this solution will restrict the callback function to a function taking no parameters,so you will not be able to use a function with one or more parameters as a timer callback.

ananthag

Ufolk123,
I am interested in your solution to the problem as I can't use a timer that runs in its own thread. Can you send a brief outline of what you have mentioned.
Thanks in advance,
Ananthag