You shouldn’t be messing with any adjustments based upon when it enters background or resumes, but rather just save the time that you are counting from or to (depending upon whether you are counting up or down). Then when the app starts up again, you just use that from/to time when reconstructing the timer. Likewise, … Read more
In Swift 5.1 this will work: var counter = 30 override func viewDidLoad() { super.viewDidLoad() Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(updateCounter), userInfo: nil, repeats: true) } @objc func updateCounter() { //example functionality if counter > 0 { print(“\(counter) seconds to the end of the world”) counter -= 1 } }
Unless you enable one of the Background modes, it is not gonna work. Why? You have around 10 minutes of background execution after this the timer is stopped by ios. The timer will not fire after app is locked (iOS7), since ios suspends the foreground app and bgTask will not get fire again. There is … Read more
If you need this so timers still run when you scroll your views (or maps), you need to schedule them on different run loop mode. Replace your current timer: [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(timerFired:) userInfo:nil repeats:YES]; With this one: NSTimer *timer = [NSTimer timerWithTimeInterval:0.5 target:self selector:@selector(timerFired:) userInfo:nil repeats:YES]; [[NSRunLoop mainRunLoop] addTimer:timer forMode:NSRunLoopCommonModes]; For details, check this … Read more
You just have to add your timer to the main runloop as follow: Swift 4.2 RunLoop.main.add(timer, forMode: .common) Swift 3 RunLoop.main.add(alarm, forMode: .commonModes) Swift 2.x NSRunLoop.mainRunLoop().addTimer(alarm, forMode: NSRunLoopCommonModes)
There are two problems here. The first is that your -updateFpsDisplay method loops from 0 to 99, changing the label each time through the loop. However, the label won’t actually be redrawn until control returns to the run loop. So, every 0.01 seconds, you change the label 100 times, and then the display updates once. … Read more
NSTimer is going to fire whenever the main runloop is running. Apple makes no promises that I know of to unschedule timers or to prevent the main runloop from running. It’s your responsibility to unschedule your timers and release resources when you move to the background. Apple isn’t going to do it for you. They … Read more
Don’t use NSTimer that way. NSTimer is normally used to fire a selector at some time interval. It isn’t high precision and isn’t suited to what you want to do. What you want is a High resolution timer class (using NSDate): Output: Total time was: 0.002027 milliseconds Total time was: 0.000002 seconds Total time was: … Read more
Try this shizzle… worked great for me EDIT To be honest my actual code is this: -(IBAction)clicked:(id)sender { if ([startStop.titleLabel.text isEqualToString:@”Start”]) { [startStop setTitle:@”Pause” forState:UIControlStateNormal]; [startStop setTitleColor:[UIColor redColor] forState:UIControlStateNormal]; timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(countUp) userInfo:nil repeats:YES]; timerDown = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(countDown) userInfo:nil repeats:YES]; } else if ([startStop.titleLabel.text isEqualToString:@”Pause”]) { [startStop setTitle:@”Resume” forState:UIControlStateNormal]; [startStop … Read more
You can have any class interested in when the app goes into the background receive notifications. This is a good alternative to coupling these classes with the AppDelegate. When initializing said classes: [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(appWillResignActive:) name:UIApplicationWillResignActiveNotification object:nil]; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(appWillTerminate:) name:UIApplicationWillTerminateNotification object:nil]; Responding to the notifications -(void)appWillResignActive:(NSNotification*)note { } -(void)appWillTerminate:(NSNotification*)note { [[NSNotificationCenter defaultCenter] … Read more