Invalidating a nstimer
Create a new Single View Application in your Xcode. Now, in the project Navigation, the left hand pane in Xcode, click Main. This will present to you a view controller where we will add elements for our Swift Timer.
If you check Is Valid function C , it tells you This does not indicate that there is an active timer that this handle references, but rather that it once referenced a valid timer. This does not indicate that there is an active timer that this handle references, but rather that it once referenced a valid timer. But it is not and I get "true false" Active means the Handle has received a timer (same as your definition of valid) but not executed yet.
Inside this code there are a few things that we have written in capitals; TIME_INCREMENT, FUNCTION, BOOL. Here is what they do: What we have done here is told the NSTimer() that we are going to run this every 1 second.