Fire method periodically at UITextField

Question

I try to use search controller on my tableview on this link. If user pause typing on the searchbar for 0.3 sec then it will fire fetch method.

I know how to fire method on every change in search bar using updateSearchResultsForSearchController, but it wasn't I want. Then I use search bar delegate searchBarSearchButtonClicked, but it fired only when search button on keyboard was pressed.

What I want is fire a method like when user stop typing for 0.3 sec. Is there any way to do this? Or am I going wrong with the concept of using search controller + fetch data?

Any help would be appreciated.

Answer 1

You can use an NSTimer to achieve this functionality. Simply start or restart the timer in updateSearchResultsForSearchController. Once the user stops typing long enough for the timer to fire, you can perform the search:

var searchTimer: NSTimer?

func updateSearchResultsForSearchController(searchController: UISearchController) {

    self.searchTimer?.invalidate()
    self.searchTimer = NSTimer.scheduledTimerWithTimeInterval(0.3,
                                                              target: self,
                                                              selector: #selector(ViewController.searchTimerExpired),
                                                              userInfo: nil,
                                                              repeats: false)
    }
}

@objc func searchTimerExpired() {
    self.searchTimer = nil

    // Do your search
}