Detect if "delete" button on iOS keyboard is pressed in empty UISearchBar - ios

Question

I am wondering if there is a way to detect when user press delete button or try to erase character in UISearchBar? I searched for quite a bit on Google and I tried couple of solutions where one put a whiteSpaceCharacter in the empty UITextField and the other use shouldChangeTextInRange delegate to do.
The one with empty space, the user can somehow know that there is a space there by just press hold and highlight the space so I think that was not a very good solution.
The one that use shouldChangeTextInRange does not work when the search bar is empty.
Another thing to note is that majority of the solutions I found was in Objective C and it would be great if there are some way I can do this in Swift. Or would be great if anyone can point me to the right path.

Answer 1

Don't know why you would wan't do delete when the searchBar is empty, but you can do it like this:
import UIKit
class ViewController: UIViewController, UISearchBarDelegate{
private var search : UISearchBar!
override func viewDidLoad() {
super.viewDidLoad()
search = UISearchBar()
search.frame = CGRectMake(0, 0, 200, 200)
search.delegate = self
self.view.addSubview(search)
}
func searchBar(searchBar: UISearchBar, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
let char = text.cStringUsingEncoding(NSUTF8StringEncoding)!
let isBackSpace = strcmp(char, "\\b")
if (isBackSpace == -92) {
print("Backspace was pressed")
}
return true
}
func searchBar(searchBar: UISearchBar, textDidChange searchText: String) {
if searchText == "" {
search.text = " "
}
}
}
This takes use of the UISearchBarDelegate, and finds out if backspace is pressed, via the shouldChangeTextInRange function. If the string is empty, it reapplies a whitespace to make it continuously deletable. It's kinda tacky, but the only way I know of to do it, as it doesen't register when the field is empty otherwise.
Hope it's of any use.