In this article we will learn how to set maximum character length to a UITextField and UITextView.

We go through each one separately.

UITextField:

First add UITextField to the view and conform to UITextFieldDelegate.

Next add the following delegate method for setting up the maximum limit:

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
    let currentText = textField.text ?? ""
    guard let stringRange = Range(range, in: currentText) else { return false }
    let updatedText = currentText.replacingCharacters(in: stringRange, with: string)
    return updatedText.count <= 10 // Change limit based on your requirement.
} 

Above example is for, if user asked to enter his/her mobile number, assume maximum length as 10.

Download the sample project from the bottom of this article.

UITextView:

Add UITextView to the view and conform to UITextViewDelegate.

Next add the following delegate method for setting the maximum limit:

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
    let currentText = textView.text ?? ""
    guard let stringRange = Range(range, in: currentText) else { return false }
    let updatedText = currentText.replacingCharacters(in: stringRange, with: text)
    return updatedText.count <= 50 // Change limit based on your requirement.
}

Above example is for, if user asked to enter about his/her, assume maximum limit here 50 characters.

Download sample project with example :

Swift provides default placeholder property to UITextField but not to UITextView.

So if you need a multi-line editable text view, you don’t get a pretty placeholder. Here you will learn how to add placeholder text to UItextView.


Here we will show step by step:

Step 1:

import UIKit

extension UITextView: UITextViewDelegate {
// Code
}

Step 2:

Here we are going to add label as subview in order to show placeholder text. No worries it's quite simple.

Add the following code inside the extension:

override open var bounds: CGRect {
    didSet {
        self.resizePlaceholder()
    }
}

public var placeholder: String? {
    get {
        var placeholderText: String?
        
        if let placeholderLbl = self.viewWithTag(50) as? UILabel {
            placeholderText = placeholderLbl.text
        }
        
        return placeholderText
    }
    set {
        if let placeholderLbl = self.viewWithTag(50) as! UILabel? {
            placeholderLbl.text = newValue
            placeholderLbl.sizeToFit()
        } else {
            self.addPlaceholder(newValue!)
        }
    }
}

public func textViewDidChange(_ textView: UITextView) {
    if let placeholderLbl = self.viewWithTag(50) as? UILabel {
        placeholderLbl.isHidden = self.text.characters.count > 0
    }
}

private func resizePlaceholder() {
    if let placeholderLbl = self.viewWithTag(50) as! UILabel? {
        let x = self.textContainer.lineFragmentPadding
        let y = self.textContainerInset.top - 2
        let width = self.frame.width - (x * 2)
        let height = placeholderLbl.frame.height
        
        placeholderLbl.frame = CGRect(x: x, y: y, width: width, height: height)
    }
}

private func addPlaceholder(_ placeholderText: String) {
    let placeholderLbl = UILabel()
    
    placeholderLbl.text = placeholderText
    placeholderLbl.sizeToFit()
    
    placeholderLbl.font = self.font
    placeholderLbl.textColor = UIColor.lightGray
    placeholderLbl.tag = 50
    
    placeholderLbl.isHidden = self.text.characters.count > 0
    
    self.addSubview(placeholderLbl)
    self.resizePlaceholder()
    self.delegate = self
}

Above code will work in both orientations.

Step 3:

Here we will show how to use.

Simply add placeholder to UITextView as below:

let textView = UITextView()
textView.placeholder = "Start typing here"

Get the full code here.

Adding UITextField to alertview became easy from swift 3 by using UIAlertController.

Here we will show step by step.

Step 1:

First create UIAlertController object with title and message as follow:

let alertVC = UIAlertController(title: "Enter credentials", message: "Provide Email & Password", preferredStyle: .alert)

Step 2:

Next add UITextField's to alertVC using addTextField() method as follow:

alertVC.addTextField { (textField) in
    textField.placeholder = "Email"
}
alertVC.addTextField { (textField) in
    textField.placeholder = "Password"
    textField.isSecureTextEntry = true
}

Step 3:

Then add the UIAlertAction with title and completion handler as follow:

let submitAction = UIAlertAction(title: "Submit", style: .default, handler: {
    (alert) -> Void in
    
    let emailTextField = alertVC.textFields![0] as UITextField
    let passwordTextField = alertVC.textFields![1] as UITextField
    
    print("Email -- \(emailTextField.text!), Password -- \(passwordTextField.text!)")
})

Step 4:

Finally add the UIAlertAction to alertVC and present alertVC as follow:

alertVC.addAction(submitAction)
alertVC.view.tintColor = UIColor.black
present(alertVC, animated: true)

The final output will looks like following image: