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POObjective-c timer wont invalidate
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copied!<p>Here is my situation: I am making a countdown app which works fine but does not appear to stop when I call <code>[stopWatchTimer invalidate];</code>, and I have no idea why. Here is my code:</p> <pre><code>- (IBAction)btnStartPressed:(id)sender { //Start countdown with the time on the Date Picker. timeLeft = [pkrTime countDownDuration]; [self currentCount]; lblTimer.text = time; //sets the label to the time set above pkrTime.hidden = YES; btnStart.hidden = YES; btnStop.hidden = NO; //Fire this timer every second. stopWatchTimer = [NSTimer scheduledTimerWithTimeInterval:1.0/1.0 target:self selector:@selector(reduceTimeLeft:) userInfo:nil repeats:YES]; } - (void)reduceTimeLeft:(NSTimer *)timer { //Countown timeleft by a second each time this function is called timeLeft--; // Get the system calendar NSCalendar *sysCalendar = [NSCalendar currentCalendar]; // Create the NSDates NSDate *date1 = [[NSDate alloc] init]; NSDate *date2 = [[NSDate alloc] initWithTimeInterval:timeLeft sinceDate:date1]; // Get conversion to months, days, hours, minutes unsigned int unitFlags = NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit; NSDateComponents *conversionInfo = [sysCalendar components:unitFlags fromDate:date1 toDate:date2 options:0]; int sec = [conversionInfo second]; int min = [conversionInfo minute]; int hour = [conversionInfo hour]; NSString *seconds = [NSString stringWithFormat:@"%d",sec]; NSString *minutes = [NSString stringWithFormat:@"%d",min]; if (sec <= 9) seconds = [NSString stringWithFormat:@"0%d", sec]; if (min <= 9) minutes = [NSString stringWithFormat:@"0%d", min]; if ([conversionInfo hour] == 0) time = [NSString stringWithFormat:@"%@:%@", minutes, seconds]; else time = [NSString stringWithFormat:@"%d:%@:%@", hour, minutes, seconds]; lblTimer.text = time; //sets the label to the time set above NSLog(@"%d", timeLeft); if (timeLeft == 0) { [self timerDone]; [stopWatchTimer invalidate]; stopWatchTimer = nil; } } -(void)timerDone { pkrTime.hidden = NO; btnStart.hidden = NO; btnStop.hidden = YES; UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Timer Done" message:nil delegate:self cancelButtonTitle:nil otherButtonTitles:@"Ok", nil]; [alert show]; [self playAlert]; } </code></pre> <p>Please let me know what the problem is... I cannot find a problem with my code anywhere!</p>

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