xcode-有没有办法在标签中表示UILocalNotification？

Question

At the moment in my game I have a NSTimer, when a button is clicked the timer counts down from 10 minutes to 0. At the same time the button is clicked a UILocalNotification is fired so if the user closes the app, it will fire a message when the 10 minutes reaches 0.

My problem is that if the user closes the app, and opens it before the 10 mins or changes views, the label has not kept track of the time!

So my question is how would I have a countdown timer that continues even when the app closes / changes views and is able to display this timer in a label.

Here is my code for my timer:

- (IBAction)startTimer {

mainInt = 600;

timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(countDown) userInfo:nil repeats:YES];

}

- (void)countDown {
mainInt -= 1;
int seconds = mainInt % 60;
int minutes = (mainInt - seconds) / 60;
timerLabel.text = [NSString stringWithFormat:@"%d:%.2d", minutes, seconds];
if (mainInt == 0) {
    [timer invalidate];
}
}

Code to set of UILocalNotification:

- (IBAction)startTime {
UILocalNotification * theNotification = [[UILocalNotification alloc] init];
theNotification.alertBody = @"Alert text";
theNotification.alertAction = @"Ok";
theNotification.fireDate = [NSDate dateWithTimeIntervalSinceNow:600];

[[UIApplication sharedApplication] scheduleLocalNotification:theNotification];
}

Thank you for any help!

Answer 1

You can't keep NSTimer running when your application closes or goes background.

During the application startup you can however look for your scheduled local notification. If such exist you can ask for the notification's triggering time (firedate) and compare that with the device time to set new counter value that you want show in the label.