C & iOS goal: starting a timer? NSTimer / Thread / NSDate / etc

Question

I am working on my first iOS application and launched the first error, I could not find a good answer.

Problem: I have a custom UIGestureRecognizer and it is all connected correctly, and I can run the code for every click in @selector after recognition. It was good for most things, but a little too much for others.

My goal: to make a timer that starts at a given interval to start the logic, and be able to cancel it at the time of canceling orders.

Why I ask here: there are many opportunities for solutions, but none of them stand out best. So far it’s like

• performSelector (and some variations of this)
• NSThread
• NSTimer
• NSDate
• Operation Queues
• I think I found others ...

Of all the studies, some form of threading seems like a route for transition, but I'm at a loss what works best for this situation.

Implementation example: a NSPoint is taken every 0.10 seconds, and the distance between the previous and current point is taken. [Taking the distance between each point yielded very dirty results].

Relevant Code:

 - (void)viewDidLoad { CUIVerticalSwipeHold *vSwipe = [[CUIVerticalSwipeHold alloc] initWithTarget:self action:@selector(touchHoldMove:)]; [self.view addGestureRecognizer:vSwipe]; [vSwipe requireGestureRecognizerToFail:doubleTap]; } ... - (IBAction)touchHoldMove:(UIGestureRecognizer *)sender { if (sender.state == UIGestureRecognizerStateEnded) { } if (sender.state == UIGestureRecognizerStateBegan) { } //other stuff to do goes here } 

Answer 1

Use NSTimer

Set it up like this:

  theTimer = [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(yourMethodThatYouWantRunEachTimeTheTimerFires) userInfo:nil repeats:YES]; 

Then, when you want to undo it, do something like this:

  if ([theTimer isValid]) { [theTimer invalidate]; } 

Note that in the example above, you need to declare an instance of "theTimer" NSTimer, where it will be available for both methods. In the above example, “0.5” means that the timer will fire twice a second. Adjust if necessary.

Answer 2

For completeness, I add my latest implementation here (not sure if this is the way to do this, but here goes)

.h

 @interface { NSTimer *myTimer; } @property (nonatomic, retain) NSTimer *myTimer; 

.m

 @synthesize myTimer; ------------------------------------------- - (void)viewDidLoad { //Relevant snipet CUIVerticalSwipeHold *vSwipe = [[CUIVerticalSwipeHold alloc] initWithTarget:self action:@selector(touchHoldMove:)]; [self.view addGestureRecognizer:vSwipe]; [vSwipe requireGestureRecognizerToFail:doubleTap]; } ------------------------------------------- - (IBAction)touchHoldMove:(UIGestureRecognizer *)sender { if (sender.state == UIGestureRecognizerStateEnded) { //Cancel the timer when the gesture ends if ([myTimer isValid]) { [myTimer invalidate]; } } } if (sender.state == UIGestureRecognizerStateBegan) { //starting the timer when the gesture begins myTimer = [NSTimer scheduledTimerWithTimeInterval:someTimeIncrement target:self selector:@selector(someSelector) userInfo:nil repeats:YES]; } }