I declared delay and it is giving me an error, I am trying to slow down the timer.
//Updates Timer
func updateTimer() {
var delay: Int
seconds += 1
self.timerLabel.text = String(self.seconds * 0.01)
timer = NSTimer.scheduledTimerWithTimeInterval(-2.0, target: self, selector: #selector(GameScene.delay), userInfo: nil, repeats: false)
The message is telling you that there is no selector for GameScene.delay. You need a func that matches this name. Note that because you have used "GameScene" rather than "gameScene", it may be a class, in which case you would need a "class func" called delay. However, more likely is you would want "self.delay" to be called. ie. one of
func delay(timer: NSTimer) { ... }
class func delay(timer: NSTimer) { ... }
Also, what are you trying to achieve with "-2.0"? You can't run a timer in the past - if will default to 0.1 if <= 0.
the selector portion of a NSTimer is meant to run a function so you declare the function then the timer should be placed outside of the function instead of inside the function
func updateTimer() {
var delay: Int
seconds += 1
self.timerLabel.text = String(self.seconds * 0.01)}
let timer = NSTimer.scheduledTimerWithTimeInterval(2.0, target: self, selector: #selector(self.updateTimer), userInfo: nil, repeats: false)
also could you be more specific when you say you are trying to slow down the timer so
Related
I'm pretty new to Swift, been practicing for about a week now. I've declared a timer, I call the function of the timer with viewDidLoad(), and the timers #selector points to goldPerSec, that function is a simple while loop, yet it's not executing every second as it should.
Here's my code:
var timer = Timer()
override func viewDidLoad() {
super.viewDidLoad()
counter()
}
func counter() {
timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(self.goldPerSec), userInfo: nil, repeats: true)
}
#objc func goldPerSec() {
while (totalOwned >= 1) {
Gold += (minerOwned * 1)
goldLabel.text = "\(Gold)"
}
}
Your while loop in goldPerSec runs forever preventing any other code from running on the main queue, including the timer.
Change the while loop to an if statement.
#objc func goldPerSec() {
if totalOwned >= 1 {
Gold += minerOwned * 1
goldLabel.text = "\(Gold)"
}
}
This will now allow goldPerSec to be called every second from the timer and also allow the rest of your user interface to work.
As a side note, variable names should start with lowercase letters so Gold should be named gold.
I try to make a refresh for a label every second in swift 3.
I alway get the following error:
Showing Recent Issues
Command failed due to signal: Segmentation fault: 11
This is the Code I've used:
var TimerBeacon = Timer.scheduledTimer(timeInterval: 1, target: self,
selector: Selector(("Timer")), userInfo: nil, repeats: true)
func Timer() {
//here is the label to refresh
}
I hope someone could help me :)
It looks like your code isn't updated for Swift 3, and could use some better naming conventions.
Create the timer:
let timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(update), userInfo: nil, repeats: true)
This is the function that the timer will call every second:
func update() {
// here is the label to refresh
}
When you want to stop the timer, call invalidate():
timer.invalidate()
You can achieve the same without timer. Use the following code
var iteration = 0
func updateLabel() {
iteration = iteration == Int.max ? 0 : (iteration + 1)
DispatchQueue.main.asyncAfter(deadline: .now() + 1, execute: {
self.label.text = "\(self.iteration)"
self.updateLabel()
})
}
}
Note that I have taken iteration just for example. You can update the label the way you want.
I want to call the method func adjustmentBestSongBpmHeartRate() every 1.1 second. I used Timer, but it doesn't work. I have read the document and found a lot of sample code, it still does work! Is there anything I missed?
timer = Timer.scheduledTimer(timeInterval: 1.1, target: self, selector: #selector(self.adjustmentBestSongBpmHeartRate), userInfo: nil, repeats: false)
timer.fire()
func adjustmentBestSongBpmHeartRate() {
print("frr")
}
I found that creating the timer in an OperationQueue Operation did not work. I assume this is because there is no runloop.
Therefore, the following code fixed my problem:
DispatchQueue.main.async {
// timer needs a runloop?
self.timeoutTimer = Timer.scheduledTimer(timeInterval: self.timeout, target: self, selector: #selector(self.onTimeout(_:)), userInfo: nil, repeats: false)
}
Timer methods with a selector are supposed to have one parameter: The timer itself. Thus your code should really look like this: 1
Timer.scheduledTimer(timeInterval: 1.1,
target: self,
selector: #selector(self.adjustmentBestSongBpmHeartRate(_:),
userInfo: nil,
repeats: false)
#objc func adjustmentBestSongBpmHeartRate(_ timer: Timer) {
print("frr")
}
Note that if your app only runs on iOS >= 10, you can use the new method that takes a block to invoke rather than a target/selector. Much cleaner and more type-safe:
class func scheduledTimer(withTimeInterval interval: TimeInterval,
repeats: Bool,
block: #escaping (Timer) -> Void) -> Timer
That code would look like this:
timer = Timer.scheduledTimer(withTimeInterval: 1.1,
repeats: false) {
timer in
//Put the code that be called by the timer here.
print("frr")
}
Note that if your timer block/closure needs access to instance variables from your class you have to take special care with self. Here's a good pattern for that sort of code:
timer = Timer.scheduledTimer(withTimeInterval: 1.1,
repeats: false) {
//"[weak self]" creates a "capture group" for timer
[weak self] timer in
//Add a guard statement to bail out of the timer code
//if the object has been freed.
guard let strongSelf = self else {
return
}
//Put the code that be called by the timer here.
print(strongSelf.someProperty)
strongSelf.someOtherProperty = someValue
}
Edit (updated 15 December)
1: I should add that the method you use in the selector has to use Objective-C dynamic dispatch. In Swift 4 and later, the individual methods you reference must be tagged with the #objc tag. In previous versions of Swift you could also declare the entire class that defines the selector with the #objc qualifier, or you could make the class that defined the selector a subclass of NSObject or any class that inherits from NSOBject. (It's quite common to define the method the timer calls inside a UIViewController, which is a subclass of NSObject, so it used to "just work".
Swift 3
In my case it worked after I added to my method the #obj prefix
Class TestClass {
private var timer: Timer?
func start() {
guard timer == nil else { return }
timer = Timer.scheduledTimer(timeInterval: 60, target: self, selector: #selector(handleMyFunction), userInfo: nil, repeats: false)
}
func stop() {
guard timer != nil else { return }
timer?.invalidate()
timer = nil
}
#objc func handleMyFunction() {
// Code here
}
}
Try this -
if #available(iOS 10.0, *) {
self.timer = Timer.scheduledTimer(withTimeInterval: 0.2, repeats: false, block: { _ in
self.update()
})
} else {
self.timer = Timer.scheduledTimer(timeInterval: 0.2, target: self, selector: #selector(self.update), userInfo: nil, repeats: false)
}
Mostly the problem must have been because of iOS version of mobile.
Swift 5, Swift 4 Simple way only call with Dispatch Queue Async
DispatchQueue.main.async
{
self.andicator.stopAnimating()
self.bgv.isHidden = true
Timer.scheduledTimer(withTimeInterval: 1.0, repeats: false, block: { _ in
obj.showAlert(title: "Successfully!", message: "Video save successfully to Library directory.", viewController: self)
})
}
I have solved the question asked by myself.
I'm using apple watch to control my iphone app.
I try to press a button on apple watch to present a new viewcontroller on iphone.
When I write Timer in override func viewDidLoad(), Timer doesn't work. I move Timer to override func viewWillAppear() it works.
I think maybe there's something wrong with controlling by apple watch
I found that if you try to initialize the timer directly at the class-level, it won't work if you're targeting a selector in that same class. When it fires, it can't find the selector.
To get around this, I only initialize the timer after the object containing the selector has been initialized. If it's in the same class, put the initialization code in the ViewDidLoad or similar. Just not in the initializer. Then it will work. No dispatch queue needed.
Also, you do not need to use a selector that accepts the timer as a parameter. You can, but contrary to the answer with a ton of votes, that's not actually true, or more specifically, it works fine for me without it, just as you have it without it.
By the way, I think the reason the dispatch queue worked is because you're forcing the timer to be created after the object was initializing, confirming my above statement.
let timer:Timer?
override func viewDidLoad(){
super.viewDidLoad()
timer = Timer.scheduledTimer(timeInterval: 1.1, target: self, selector: #selector(adjustmentBestSongBpmHeartRate), userInfo: nil, repeats: false)
timer.fire()
}
func adjustmentBestSongBpmHeartRate() {
print("frr")
}
Note: This is code typed from memory, not copied from Xcode so it may not compile, but hopefully you get the idea.
Swift3
var timer = Timer()
timer = Timer.scheduledTimer(timeInterval: 5, target: self, selector: #selector(self.compruebaConexion), userInfo: nil, repeats: true)
my two cents.
I read about "didLoad" and when invoking it.
so we can use a delay:
class ViewController: UIViewController {
var timer: Timer?
override func viewDidLoad() {
super.viewDidLoad()
startTimer()
}
final func killTimer(){
self.timer?.invalidate()
self.timer = nil
}
final private func startTimer() {
// make it re-entrant:
// if timer is running, kill it and start from scratch
self.killTimer()
let fire = Date().addingTimeInterval(1)
let deltaT : TimeInterval = 1.0
self.timer = Timer(fire: fire, interval: deltaT, repeats: true, block: { (t: Timer) in
print("hello")
})
RunLoop.main.add(self.timer!, forMode: RunLoopMode.commonModes)
}
How can I iterate a for loop overtime in swift? A typical loop will execute immediately as fast as possible. However, I would like to expand the time in which the loop occurs.
Say I have the following loop:
for var i = 0; i < 4; i+=1{
print(i)
}
And I wanted this loop to occur over a span of 1 second, each iteration taking 0.25 seconds. How could I do this? Thanks for any help
You might want to create a Timer like this:
timer = NSTimer.scheduledTimerWithTimeInterval(0.25, target: self, selector: #selector(MyClass.tic), userInfo: nil, repeats: true)
time.fire() //first time
this timer will call the function selected with #selector when it fires, and will fire every 0.25 secondes (first parameter) until you invalidate it. So when you have ended your loops you can
call timer.invalidate()
tic() is a function you can define, and can have any name you want:
func tic() {
numberOfTimeFired = numberOfTimeFired + 1
print(numberOfTimeFired)
}
In Swift 3 the timer declaration would be:
timer = Timer.scheduledTimer(timeInterval: 0.25, target: self, selector: #selector(MyClass.tic), userInfo: nil, repeats: true)
I have this problem for a few days now and I don't get what I am doing wrong.
My application is basically just creating some timers. I need to stop them and create new ones. But at the moment stopping them doesn't work.
self.timer = NSTimer.scheduledTimerWithTimeInterval(timeInterval, target:self, selector: "timerDidEnd:", userInfo: "Notification fired", repeats: false)
That's my timer
func timerDidEnd(timer:NSTimer){
createUnrepeatedAlarmWithUpdateInterval()
}
Because my timer didn't want to stop I am currently using the unrepeated timer and start it myself after it stopped.
func stopAlarm() {
if self.timer != nil {
self.timer!.invalidate()
}
self.timer = nil
self.timer = NSTimer()
}
And that's how I stop my timer.
alarmManager.stopAlarm()
alarmManager.createUnrepeatedAlarmWithUpdateInterval()
I call the stopAlarm() function before creating a new timer.
I really don't know what I am doing wrong so I appreciate every answer :)
class AlarmManager: ViewController{
private var timer : NSTimer?
private var unrepeatedTimer : NSTimer?
private let notificationManager = NotificationManager()
private var current = NSThread()
private let settingsViewController = SettingsViewController()
func createRepeatedAlarmWithUpdateInterval(){
var timeInterval:NSTimeInterval = settingsViewController.getUpdateIntervalSettings()
if timer == nil{
timer = NSTimer.scheduledTimerWithTimeInterval(timeInterval,
target: self,
selector: "repeatedTimerDidEnd:",
userInfo: "Notification fired",
repeats: true)
}
}
func repeatedTimerDidEnd(repeatedTimer:NSTimer){
ConnectionManager.sharedInstance.loadTrainings(settingsViewController.getServerSettings())
createUnrepeatedAlarm(10)
}
func createUnrepeatedAlarm(timeInterval:Double){
unrepeatedTimer = NSTimer.scheduledTimerWithTimeInterval(timeInterval,
target: self,
selector: "unrepeatedTimerDidEnd:",
userInfo: "Notification fired",
repeats: false)
}
func unrepeatedTimerDidEnd(unrepeatedTimer:NSTimer){
notificationManager.createNotification(self, reminderType: NotificationManager.ITEMRATINGREMINDER)
notificationManager.createNotification(self, reminderType: NotificationManager.ITEMREMINDER)
print("UnrepeatedAlarm ended")
}
func stopAlarm(){
print("StopAlarm triggered")
if (timer != nil)
{
print("stoptimer executed")
timer!.invalidate()
timer = nil
}
if (unrepeatedTimer != nil)
{
unrepeatedTimer!.invalidate()
unrepeatedTimer = nil
}
}
}
Thats the whole code of this class. Maybe that helps :D
The usual way to start and stop a timer safely is
var timer : Timer?
func startTimer()
{
if timer == nil {
timer = Timer.scheduledTimer(timeInterval: timeInterval, target: self, selector: #selector(timerFired), userInfo: nil, repeats: true)
}
}
func stopTimer()
{
timer?.invalidate()
timer = nil
}
startTimer() starts the timer only if it's nil and stopTimer() stops it only if it's not nil.
You have only to take care of stopping the timer before creating/starting a new one.
Make sure you're calling invalidate on the same thread as the timer.
From the documentation:
Special Considerations
You must send this message from the thread on which the timer was installed. If you send this message from another thread, the input source associated with the timer may not be removed from its run loop, which could prevent the thread from exiting properly.
https://developer.apple.com/documentation/foundation/nstimer/1415405-invalidate?language=objc
Something that's not really covered by the previous answers is that you should be careful your timer isn't scheduled multiple times.
If you schedule a timer multiple times without first invalidating it, it'll end up scheduled on multiple run loops, and invalidating it then becomes nigh impossible.
For me, it happened when calling my scheduleTimer() function in separate functions in my view controller's life cycle (viewWillAppear, viewDidAppear, ...)
So in short, if you aren't sure (or you cannot guarantee) your Timer is only scheduled once, just always invalidate it first.
I have tried every possible solution found but not able to resolve that at the end I have set repeat "false" while initialising timer like below
self.timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(viewcontroller.methodname), userInfo: nil, repeats: false)
And need to add above line in my selector method for whatever the condition for which I wanted to repeat the time.
For example:-
My requirement is I want to repeatedly call some method until one condition satisfied. So instead of adding repeats true I set it false as repeat true does not invalidate timer in my case.
I have added below in my viewdidload method
self.timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(viewcontroller.method), userInfo: nil, repeats: false)
in selector function I added below code
#objc func method{
if condition not matched{
self.timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(viewcontroller.method), userInfo: nil, repeats: false)
}
else{
// once you are here your timer invalidate automatically
}
}
Hope this will solve your problem
For Swift 5 Xcode 12.4 there is example to use timer:
class MyController: UIViewController {
private id: Float;
func setValue(_ value: Float, withAnimation: Bool) {
let step: Float = value / 200
var current: Float = withAnimation ? 0.0 : value
let _ = Timer.scheduledTimer(withTimeInterval: 0.01, repeats: withAnimation) { timer in
DispatchQueue.main.async {
self.id = current
current += step
if current > value || withAnimation == false {
self.id = current
timer.invalidate()
}
}
}
}
}