iOS force UITextfield to use system number keyboard

Question

I set UITextField.UIKeyboardType is Number, but user can use other company's Keyboard; user can tap "返回"button, and the keyboard changed KeyboardType. KeyboardTypeChanged I want force pop system number keyboard. SystemNumberKeyboard

score 1 · Answer 1 · answered Aug 09 '16 at 12:03

1

You can use UITextField delegate for restricting only number input:

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {

  let numbersOnly = NSCharacterSet(charactersInString:"0123456789").invertedSet
  let compSepByCharInSet = string.componentsSeparatedByCharactersInSet(numbersOnly)
  let numberFiltered = compSepByCharInSet.joinWithSeparator("")
  return string == numberFiltered

}

answered Aug 09 '16 at 12:03

MCMatan

8,623
6
46
85

Does this take into account that user might have copied text from somewhere tried to paste it into the textfield which is meant to only take numbers as input? – Yash Tamakuwala Aug 09 '16 at 14:39
Yes, try it your self (: – MCMatan Aug 09 '16 at 15:15
@user5814049 did it work for you? – MCMatan Aug 19 '16 at 12:13
I hadn't tried it. But now that I did, I couldn't make it work. – Yash Tamakuwala Aug 19 '16 at 13:07
Did you set the view/viewController with "shouldChangeCharactersInRange" function as the delegate of the TextFiled? – MCMatan Aug 19 '16 at 13:14
I did - class ViewController: UIViewController, UITextFieldDelegate. and copy pasted the above function. Did I miss something? – Yash Tamakuwala Aug 19 '16 at 13:21
@YashTamakuwala You should still set the delegate as your view, by "self.textField.delegate = self" – MCMatan Aug 19 '16 at 13:22
@YashTamakuwala If it works, please accept my answer. – MCMatan Aug 19 '16 at 14:38

score 0 · Answer 2 · answered Aug 10 '16 at 04:49

In Objective-C you can do it like this by implementing UITextfield delegate method. Textfield will only allows number to be entered.

-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {

NSCharacterSet *CS = [[NSCharacterSet characterSetWithCharactersInString:@"0123456789"] invertedSet];

NSString *filtered=[[string componentsSeparatedByCharactersInSet:CS] componentsJoinedByString:@""];

return [string isEqualToString:filtered];

}

iOS force UITextfield to use system number keyboard

2 Answers2