ios - The number of digits on textField -

i'm working on app , need on uitextfield.

i want make number of digits appear specific (e.g. 3) knowing numbers shown on uitextfield value of slider between range of 1 0 (i need range,) numbers between them (0.5 , 0.6 ...).

the numbers getting 6 digits (0.123456) , show less that.

i have tried funcion after added uitextfielddelegate:

func textfield(textfield: uitextfield, shouldchangecharactersinrange range: nsrange, replacementstring string: string) -> bool { ... } 

but it's not working. got 1 use function:

@ibaction func testfield(sender: uitextfield) {     let thelength = sender.text!.characters.count     if thelength = >= 3 {         let therange = range(start: sender.text!.startindex, end: sender.text!.startindex.advancedby(3))         var newdi = sender.text!.substringwithrange(therange)         sender.text = newdi     } }  

also nothing changed.

note: have more uitextfields fix.

use this.

textfield.text = string(format: "%0.1f", slider.value)