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# init(timeInterval:invocation:repeats:)

Initializes a timer object with the specified invocation object.

```
init(timeInterval ti: TimeInterval, invocation: NSInvocation, repeats yesOrNo: Bool)
```

## Parameters

`ti`

The number of seconds between firings of the timer. If `ti` is less than or equal to `0.0`, this method chooses the nonnegative value of `0.0001` seconds instead.

`invocation`

The invocation to use when the timer fires. The timer instructs the invocation object to maintain a strong reference to its arguments.

`yesOrNo`

If <doc://com.apple.documentation/documentation/Swift/true>, the timer will repeatedly reschedule itself until invalidated. If <doc://com.apple.documentation/documentation/Swift/false>, the timer will be invalidated after it fires.

## Return Value

A new `NSTimer` object, configured according to the specified parameters.

## Discussion

You must add the new timer to a run loop, using [`add(_:forMode:)`](/documentation/Foundation/RunLoop/add(_:forMode:)-392ag). Then, after `ti` have elapsed, the timer fires, invoking `invocation`. (If the timer is configured to repeat, there is no need to subsequently re-add the timer to the run loop.)

---

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