I want to make a label that's text changes from "Loading" -> "Loading." ->"Loading.." -> "Loading..." dynamically and for as long as that label exists.
So I just created a label and added a function that I call called animateDots that just keeps calling itself. I had it done using UIView.animateWithDuration() and every completion block calls another animateWithDuration() until it just calls animateDots() and so on. But that didn't work because the text in a UILabel isn't animatable so it just animates all four labels really fast. I want it to be slow.
I tried UIView.preformWithoutAnimation and I also tried UIView.beginAnimations but I can't recall animateDots() without causing the app to crash. I have no idea what else to try
Edit: Here's how I solved it thanks to #7vikram7 's suggestion.
I created the timer right after I initialize the label, and the timer repeats. Every time the timer finishes a loop, it runs a selector, in this case animateDots, which changes the text. In Code:
Add this whenever you want to start the animation process:
loading = UILabel(frame: CGRectMake(0,0,80,50))
loading.text = "Loading"
let timer = NSTimer.scheduledTimerWithTimeInterval(0.5, target: self, selector:
#selector(LoadingCell.animateDots), userInfo: nil, repeats: true)
timer.fire()
Then add this function:
func animateDots() {
switch (loading.text!) {
case "Loading...":
loading.text = "Loading"
case "Loading":
loading.text = "Loading."
case "Loading.":
loading.text = "Loading.."
case "Loading..":
loading.text = "Loading..."
default:
loading.text = "Loading"
}
}
You can use NSTimer. Schedule a timer with interval of 2 or 3 seconds which repeats.
https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSTimer_Class/
Copy and past into your project and change value of timer and seconds
Start timer when you want to animation of text and stop when is not in use
NSTimer *myticker = [NSTimer scheduledTimerWithTimeInterval:(set your time) target:self selector:#selector(showActivity) userInfo:nil repeats:YES];
-(void)showActivity {
second=second-0.5; // set your second
if (second <= 0) {
[myticker invalidate];
}
if (second >= 5) {
if ([connectingLabel.text isEqualToString:#"Connecting."]) {
connectingLabel.text = #"Connecting..";
}else if ([connectingLabel.text isEqualToString:#"Connecting.."]) {
connectingLabel.text = #"Connecting...";
}else if ([connectingLabel.text isEqualToString:#"Connecting..."]) {
connectingLabel.text = #"Connecting.";
}else{
connectingLabel.text = #"Connecting.";
}
}else{
connectingLabel.text = #"";
}
}
Swift 5 Version of Wos answer
var myticker : Timer?
func LabelAnimating() {
myticker = Timer.scheduledTimer(timeInterval: 0.5, target: self, selector: #selector(showLoading), userInfo: nil, repeats: true)
}
#objc func showLoading() {
if findingTripsLbl.text == "Connecting." {
findingTripsLbl.text = "Connecting.."
} else if findingTripsLbl.text == "Connecting.." {
findingTripsLbl.text = "Connecting..."
} else if findingTripsLbl.text == "Connecting..." {
findingTripsLbl.text = "Connecting."
} else {
findingTripsLbl.text = "Connecting."
}}
func StopLoading() {
myticker?.invalidate()
}
You can also create 4 images like that and you can set the animation for uiimageview. It gives the same result as you want.
MarqueeLabel can help you achieve this with little modification. Either you make your Loading text a different label and make your DOTS text a MarqueeLabel or you completely make all three dots different labels hiding and unhiding them respectively. The latter is a very tedious method and is highly unrecommended, hence use first.
pod MarqueeLabel
MarqueeLabel provides this feature. Just set the class name of your label to MarqueeLabel as:
#IBOutlet weak var lblLocation: MarqueeLabel!
Set the properties according to your requirement:
Duration
FadeLength
MarqueeType
Related
I am making an app where the user can have multiple timers going at once and see them in a list view.
I am aware that there are 2 main options for working out time:
Subtract the date started from current date (current date-start date)
OR
Use an NSTimer and take away 1 second every second from each active timer.
I have previously been using the latter, but having looked around the internet I am starting to think that the data one may be better.
Please could you let me know which you think is best to use, and if you chose the first one (dates), please could you provide some sample code on how to use it.
You can Use an NSTimer and take away 1 second every second from each active timer. You can use this class.
class CustomTimer {
typealias Update = (Int)->Void
var timer:Timer?
var count: Int = 0
var update: Update?
init(update:#escaping Update){
self.update = update
}
func start(){
timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(timerUpdate), userInfo: nil, repeats: true)
}
func stop(){
if let timer = timer {
timer.invalidate()
}
}
/**
* This method must be in the public or scope
*/
#objc func timerUpdate() {
count += 1;
if let update = update {
update(count)
}
}
}
To use multiple timer you can create multiple instance of CustomTimer, Example Code:
let timer1 = CustomTimer { (seconds) in
// do whatever you want
}
timer1.start()
let timer2 = CustomTimer { (seconds) in
// do whatever you want
}
timer2.start()
NOTE:
timerUpdate method will be called exactly at 1 second interval. to keep some space for function execution we can set interval to 0.9 or 0.95 according to time taken by execution.
You use both. You have one Timer that repeats every second. The handler for the Timer then iterates through your list of start dates for each of the user's timers and you update the display for each based on the current date.
I'm looking for a way to exit a function without using guard. After extensive searching, I cannot find a way to exit a function and call the next at the same time when a button it pressed.
The button calls a repeat using a selector:
#IBAction func BottomLeft(sender: AnyObject) {
NSTimer.scheduledTimerWithTimeInterval(NSTimeInterval(0.01), target: self, selector: "bottomLeftMovement", userInfo: nil, repeats: true)
}
This is when the code button is pressed, and the ball will follow this movement:
func bottomLeftMovement() {
Ballx = Ballx - 0.6125
Bally = Bally + 1.2
self.Ball.center.x = Ballx
self.Ball.center.y = Bally
}
I am looking to make it so that when a different button is pressed, that this function will be exited and the corresponding one will be called.
I cannot hard program into the first function, as it is an interchangeable thing, as opposed to a function chain.
Any help would be much appreciated.
What your code is doing is creating a new timer every time you tap on the button. This is not the correct way to do this. I'd recommend you do some research/reading on game development.
But basically, if you're gonna do things this way (which again, is not a good thing (tm)). You need to keep track of your timer in a property, and invalidate it (to stop it). Read about timers too (https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSTimer_Class/)
So, in short:
- don't do this
- if you must, track your timer in a property
- invalidate() your timer and start a new one as required
Note: Track and invalidate the timer like this:
(note I'm doing this from memory, not tested, but something along the lines of...)
class someClass {
var myTimer = NSTimer?
func myFunction() {
if let timer = myTimer {
timer.invalidate()
}
timer = NSTimer(...
I have a UILabel in my app which display chat messages. These chat messages are hardcoded as an array of strings. What i need is to display these messages one by one on a UILabel but i need to have a certain 2 second delay between switching messages as user need to read each message.
What i have implemented is the following code:
for chatText in chatDialogue{
dispatch_async(dispatch_get_main_queue(), {
chatLabel.text=chatText as? String
})
println(chatText)
NSThread .sleepForTimeInterval(2)
}
here we have an array of chatDialogues
["Hello","How are you?","Can you say DIAS","Wait Please"]
Now i need these to be displayed on the same label but with a say delay between changing messages.
The above implementation when executed showed only the last message on the loop.
Set up a NSTimer which fires every 2 seconds and stops when reaching the last text:
// instance variables
let chatDialoges = ["Hello","How are you?","Can you say DIAS","Wait Please"]
var textIndex = 0
var timer: NSTimer?
// ...
// somewhere where the timer should start
self.timer = NSTimer.scheduledTimerWithTimeInterval(2, target: self, selector: "update", userInfo: nil, repeats: true)
//
func update() {
self.textLabel++
if self.textLabel == chatDialoges.count {
self.timer?.invalidate()
return
}
chatLabel.text = chatDialoges[self.textIndex]
}
I have a strange problem with my countdown timer. It fires off normally when my start button is hit, and is reinstantiated correctly when I close the app and relaunch it again. However, when I select a different tab and stay there for a while, it stops counting down, then resumes counting down from where it left off when I show the countdown tab again.
For example, if the timer is now at 00:28:00 (format is HH:MM:SS), select some other tab, stay there for 5 minutes, and then go back to the timer tab, it's only at the 27:52 mark. When I close the app (double tap the home button, swipe up my app) and reopen it, it starts off at a more reasonable 22:50 mark.
I've posted the relevant code from the class to show how I'm setting up the timer, but a summary of what it does:
I have plus (+) and minus (-) buttons somewhere that, when tapped, call recalculate().
recalculate() fires off a CalculateOperation.
A CalculateOperation computes for the starting HH:MM:ss based on the addition/removal of a new record. The successBlock of a CalculateOperation executes in the main thread.
A CalculateOperation creates the NSTimer in the successBlock if the countdownTimer hasn't been created yet.
The NSTimer executes decayCalculation() every 1 second. It reduces the calculation.timer by 1 second by calling tick().
Code:
class CalculatorViewController: MQLoadableViewController {
let calculationQueue: NSOperationQueue // Initialized in init()
var calculation: Calculation?
var countdownTimer: NSTimer?
func recalculate() {
if let profile = AppState.sharedState.currentProfile {
// Cancel all calculation operations.
self.calculationQueue.cancelAllOperations()
let calculateOperation = self.createCalculateOperation(profile)
self.calculationQueue.addOperation(calculateOperation)
}
}
func decayCalculation() {
if let calculation = self.calculation {
// tick() subtracts 1 second from the timer and adjusts the
// hours and minutes accordingly. Returns true when the timer
// goes down to 00:00:00.
let timerFinished = calculation.timer.tick()
// Pass the calculation object to update the timer label
// and other things.
if let mainView = self.primaryView as? CalculatorView {
mainView.calculation = calculation
}
// Invalidate the timer when it hits 00:00:00.
if timerFinished == true {
if let countdownTimer = self.countdownTimer {
countdownTimer.invalidate()
}
}
}
}
func createCalculateOperation(profile: Profile) -> CalculateOperation {
let calculateOperation = CalculateOperation(profile: profile)
calculateOperation.successBlock = {[unowned self] result in
if let calculation = result as? Calculation {
self.calculation = calculation
/* Hide the loading screen, show the calculation results, etc. */
// Create the NSTimer.
if self.countdownTimer == nil {
self.countdownTimer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("decayCalculation"), userInfo: nil, repeats: true)
}
}
}
return calculateOperation
}
}
Well, if I leave the app in some other tab and not touch the phone for a while, it eventually goes to sleep, the app resigns active, and enters the background, which stops the timer.
The solution was to set my view controller as a listener to the UIApplicationWillEnterForegroundNotification and call recalculate to correct my timer's countdown value.
Newbie to IOS programming - learning through Swift. I'm writing a simple "slot machine / dice game".
I'm trying to show the user a flashing sequence of rolls before the "actual" roll appears.
func doFancyDiceRoll() {
for x in 1...100 {
Die1.image = PipsImg[RollOne()]
Die2.image = PipsImg[RollOne()]
Die3.image = PipsImg[RollOne()]
}
}
Die1, etc., are defined as generic UIImage views.
In any case, I'm not seeing the 100x iterations, just the images at the end of the loop. I'm assuming that either it redraws "too fast" or that IOS is trying to be smart, and only draws the last images so as to conserve resources.
I'll wildly guess that I need to either implement some kind of delay here, or, IOS needs to be told to explicitly draw out my images, and not try to outthink my intent.
For the delay, I've seen something about NSTimer, but nothing I saw seems to simply say something like "pause for .05" second, and the whole construct was unclear as they were ObjC examples/conversions.
(Note: I've simplified things here --- normally, I would store the value of RollOne() so I can use it later. I also would like to make an array (or collection?) like Die[1].image, but that is another question.)
========== Edit =======
OK, so I'm following up with more of my original code, merged in with that of #doctordoder so we can discuss a bit better. Hopefully that is kosher. (If this appended question is too long, please advise me on the best way to post a lengthy follow-up directly.)
import UIKit
class ViewController: UIViewController {
//( stripping out stuff unneeded for discussion )
// refers to same label below - works but kosher??
#IBOutlet var btnRoll_x: UIView
#IBAction func btnRoll(sender: AnyObject) {
triggerRoll()
}
var timer : NSTimer? = nil
var rolls : Int = 0
func triggerRoll() {
//hiding is bad UI, but until i know how to "disable & dim"
btnRoll_x.hidden = true
timer = NSTimer.scheduledTimerWithTimeInterval(0.10, target: self, selector: "doFancyDiceRoll", userInfo: nil, repeats: true);
}
func doFancyDiceRoll() {
Die1.image = PipsImg[randomInt(6)]
Die2.image = PipsImg[randomInt(6)]
Die3.image = PipsImg[randomInt(6)]
if (++rolls > 10)
{
timer?.invalidate()
timer = nil
rolls = 0 // DCB added this presumed missing line
btnRoll_x.hidden = false //again, need to do this better
}
}
}
Hopefully, my implementation of the code is what would have been intended. I made some minor adjustments for (hopeful) clarity.
Good news is I have working code. I have just enough understanding to get in place, but I'm fuzzy on some details.
Here is what I (think I) know...
We declare an NSTImer object, and a roll counter at the main level of the class. I note that in my original version, I had the roll counter scoped within the rolling function itself. Took me a while to understand why it could not live in the DiceRoll loop itself, but now I do. I'm going to express it poorly, but since the timer is going to call DiceRoll multiple instances, it needs to live outside the function.
The button btnRoll gets touched, and invokes triggerRoll().
To prevent the user from touching the button while we are in progress, which put us into a state where the roll counter never got to zero, I hide the button. (I'll figure how to properly put in in disabled state later.)
The timer is set. It fires every .1 second (within limits), and is set to repeat. (until .invalidate ). And it "calls" the function doFancyDiceRoll via the selector: attribute.
So, the big change as previously noted is that doFancy..Roll() no longer loops. It excites a single instance up updating the images. It checks the counter, and if we reach the limit, we kill the timer, which stops the timer (invalidate). (And I unhide the button, making it available again.)
So, a few things I am concerned/wondering about: I get the value of timers for other things that need to happen periodically (take health away every second, check a GPS position every 10 seconds, etc.). It's seems a odd construct to force a screen refresh.
Frankly, I would have expected to see see something like this:
func doFancyDiceRoll() {
for x in 1...100 {
Die1.image = PipsImg[RollOne()] // and 2 and 3 of course.....
VIewController.forceRedraw <<=== something like this, or maybe
ViewController.wait(.05) <<== this?? I dunno ;-)
}
}
instead we end up with about 20 extra lines or so. I'd be interested in knowing if there other approaches that could work keeping the loop intact.
Anyway, assuming this is the one true way to go, I guess my followup to this is how do I pass parameters, since this is not a "real" function call. Trying
selector: "doFancyDiceRoll(40)"
was not objected to by the IDE, but failed in execution.
I had exactly same problem back in days, entire loop is finished before the view is refreshed as #doctordoder mentioned. Solved with using NSTimer
var rollCount = 0
let arrayOfImages = ["image01", "image02", "image03"]
var timer = NSTimer.scheduledTimerWithTimeInterval(0.1, target: self, selector: Selector("doFancyDiceRoll"), userInfo: nil, repeats: true)
func doFancyDiceRoll() {
if rollCount == 100 {
timer.invalidate
rollCount = 0
{
else {
//get images from array arrayOfImages[rollCount]
rollCount++
}
}
there could be typos, since I have no Xcode right now.
I have basically the same answer as above :(, but I thought I'd post it anyway.
var timer : NSTimer? = nil
var rolls : Int = 0
func doFancyDiceRoll() {
timer = NSTimer.scheduledTimerWithTimeInterval(0.10, target: self, selector: "roll", userInfo: nil, repeats: true);
}
func roll() {
println("rolling")
Die1.image = PipsImg[RollOne()]
Die2.image = PipsImg[RollOne()]
Die3.image = PipsImg[RollOne()]
if (++rolls > 100)
{
timer?.invalidate()
timer = nil
}
}
Rather than NSTimer and invalidating, you can use dispatch_after to do the work for you.
func rollDice(howManyTimes: Int) {
die1.image = PipsImg[RollOne()]
die2.image = PipsImg[RollOne()]
die3.image = PipsImg[RollOne()]
if howManyTimes > 0 {
let delayTime = dispatch_time(DISPATCH_TIME_NOW, Int64(Double(NSEC_PER_SEC) / 10.0))
dispatch_after(delayTime, dispatch_get_main_queue()) {
self.rollDice(howManyTimes - 1)
}
}
}
This will run the code for the number of times specified, delaying each time by 0.1 seconds. It works like this: First it sets the images on each die, then, if there are more iterations, it does a dispatch_after to call itself with rollDice(howManyTimes - 1)
With this, you don't need to maintain a NSTimer and it is pretty self contained.