Question

I want to get the time difference in hundredth second between two touches

float starttime;
float endtime;

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

    starttime = [[NSDate date] timeIntervalSince1970];

}

-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{

      endtime = [[NSDate date] timeIntervalSince1970];

      NSLog(@"starttime %f endtime %f",starttime,endtime);

      float diff = endtime - starttime;


}

1. the problem is i found both endtime and starttime is same , no matter how long i touch, but if i remove timeIntervalSince1970 , it’s not

2. is there any method to get that difference

Answer 1

I’d better use

double startTime = CACurrentMediaTime();

This is recommended way for relative timings

double starttime;
double endtime;

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

    startTime = CACurrentMediaTime();
}

-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{

    endtime = CACurrentMediaTime();
    NSLog(@"starttime %f endtime %f",starttime,endtime);
    double diff = endtime - starttime;
    NSLog(@"Diff - %f", diff);
}