Call extension function IOS Swift - ios

How can I call extension function, so that the button is encouraged to call the view.
I made a UiButton Extension with a function to animate a button, and everything works, but only if I call it from:
#IBAction func botonVuelta(_ sender: UIButton) {
sender.pulsarAnimacion()
}
but if you called it from viewDidLoad it doesn’t work:
override func viewDidLoad() {
super.viewDidLoad()
botones.layer.cornerRadius = 20
botones.pulsarAnimacion()
}
I’d appreciate it if you could give me a solution,
I thank you in advance

viewDidLoad is a very early place to animate a view , try inside
override func viewDidAppear(_ animated:bool) {
super.viewDidAppear(animated)
botones.pulsarAnimacion()
}

Related

how to hide keyboard on text view to return in swift3 [duplicate]

I am using UITextfied while clicking on textfied keyboard appear but when i pressed the return key, keyboard is not disappearing. I used the following code:
func textFieldShouldReturn(textField: UITextField!) -> Bool // called when 'return' key pressed. return NO to ignore.
{
return true;
}
the method resignfirstresponder is not getting in function.
You can make the app dismiss the keyboard using the following function
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
self.view.endEditing(true)
return false
}
Here is a full example to better illustrate that:
//
// ViewController.swift
//
//
import UIKit
class ViewController: UIViewController, UITextFieldDelegate {
#IBOutlet var myTextField : UITextField
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.myTextField.delegate = self
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
self.view.endEditing(true)
return false
}
}
Code source: http://www.snip2code.com/Snippet/85930/swift-delegate-sample
The return true part of this only tells the text field whether or not it is allowed to return.
You have to manually tell the text field to dismiss the keyboard (or what ever its first responder is), and this is done with resignFirstResponder(), like so:
// Called on 'Return' pressed. Return false to ignore.
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
No Delegate Needed
You can create an action outlet from the UITextField for the "Primary Action Triggered" and resign first responder on the sender parameter passed in:
#IBAction func done(_ sender: UITextField) {
sender.resignFirstResponder()
}
Super simple.
(Thanks to Scott Smith's 60-second video for tipping me off about this: https://youtu.be/v6GrnVQy7iA)
Add UITextFieldDelegate to the class declaration:
class ViewController: UIViewController, UITextFieldDelegate
Connect the textfield or write it programmatically
#IBOutlet weak var userText: UITextField!
set your view controller as the text fields delegate in view did load:
override func viewDidLoad() {
super.viewDidLoad()
self.userText.delegate = self
}
Add the following function
func textFieldShouldReturn(userText: UITextField!) -> Bool {
userText.resignFirstResponder()
return true;
}
with all this your keyboard will begin to dismiss by touching outside the textfield aswell as by pressing return key.
I hate to add the same function to every UIViewController.
By extending UIViewController to support UITextFieldDelegate, you can provide a default behavior of "return pressed".
extension UIViewController: UITextFieldDelegate{
public func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true;
}
}
When you create new UIViewController and UITextField, all you have to do is to write one line code in your UIViewController.
override func viewDidLoad() {
super.viewDidLoad()
textField.delegate = self
}
You can even omit this one line code by hooking delegate in Main.storyboard. (Using "ctrl" and drag from UITextField to UIViewController)
Simple Swift 3 Solution:
Add this function to your view controllers that feature a text field:
#IBAction func textField(_ sender: AnyObject) {
self.view.endEditing(true);
}
Then open up your assistant editor and ensure both your Main.storyboard is on one side of your view and the desired view controller.swift file is on the other. Click on a text field and then select from the right hand side utilities panel 'Show the Connection Inspector' tab. Control drag from the 'Did End on Exit' to the above function in your swift file. Repeat for any other textfield in that scene and link to the same function.
#RSC
for me the critical addition in Xcode Version 6.2 (6C86e) is in override func viewDidLoad()
self.input.delegate = self;
Tried getting it to work with the return key for hours till I found your post, RSC. Thank you!
Also, if you want to hide the keyboard if you touch anywhere else on the screen:
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
self.view.endEditing(true);
}
To get automatic keyboard dismissal, I put this code inside one of the methods of my custom text field's class:
textField.addTarget(nil, action:"firstResponderAction:", forControlEvents:.EditingDidEndOnExit)
Substitute your outlet's name for textField.
Another way of doing this which mostly uses the storyboard and easily allows you to have multiple text fields is:
#IBAction func resignKeyboard(sender: AnyObject) {
sender.resignFirstResponder()
}
Connect all your text fields for that view controller to that action on the Did End On Exit event of each field.
Here's the Swift 3.0 update to peacetype's comment:
textField.addTarget(nil, action:Selector(("firstResponderAction:")), for:.editingDidEndOnExit)
I would sugest to init the Class from RSC:
import Foundation
import UIKit
// Don't forget the delegate!
class ViewController: UIViewController, UITextFieldDelegate {
required init(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
#IBOutlet var myTextField : UITextField?
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.myTextField.delegate = self;
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func textFieldShouldReturn(textField: UITextField!) -> Bool {
self.view.endEditing(true);
return false;
}
}
When the user taps the Done button on the text keyboard, a Did End On Exit event will be generated; at that time, we need to tell the text field to give up control so that the keyboard will go away. In order to do that, we need to add an action method to our controller class.
Select ViewController.swift add the following action method:
#IBAction func textFieldDoneEditing(sender: UITextField) {
sender.resignFirstResponder()}
Select Main.storyboard in the Project Navigator and bring up the connections inspector. Drag from the circle next to Did End On Exit to the yellow View Controller icon in the storyboard and let go. A small pop-up menu will appear containing the name of a single action, the one we just added. Click the textFieldDoneEditing action to select it and that's it.
Swift 3
Add this code below to your VC
//hide keyboard when user tapps on return key on the keyboard
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
self.view.endEditing(true);
return false;
}
Works for me
override func viewDidLoad() {
super.viewDidLoad()
let tap = UITapGestureRecognizer(target: self, action: #selector(handleScreenTap(sender:)))
self.view.addGestureRecognizer(tap)}
then you use this function
func handleScreenTap(sender: UITapGestureRecognizer) {
self.view.endEditing(true)
}
Swift
Using optional function from UITextFieldDelegate.
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.endEditing(false)
}
false means that field can be ask to resign. true – force resign.
Make sure that your textField delegate is set to the view controller from which you are writing your textfield related code in.
self.textField.delegate = self
you can put this anywhere but not in a UIButton
func TextFieldEndEditing(text fiend name: UITextField!) -> Bool
{
return (false)
}
then you can put this code in a button(also for example):
self.view.endEditing(true)
this worked for me
In the view controller you are using:
//suppose you are using the textfield label as this
#IBOutlet weak var emailLabel: UITextField!
#IBOutlet weak var passwordLabel: UITextField!
//then your viewdidload should have the code like this
override func viewDidLoad() {
super.viewDidLoad()
self.emailLabel.delegate = self
self.passwordLabel.delegate = self
}
//then you should implement the func named textFieldShouldReturn
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
// -- then, further if you want to close the keyboard when pressed somewhere else on the screen you can implement the following method too:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
self.view.endEditing(true);
}
you should connect the UITextfied with a delegate of view controller to make this function called
All in One Hide Keyboard and Move View on Keyboard Open: Swift 5
override func viewDidLoad() {
super.viewDidLoad()
let tap = UITapGestureRecognizer(target: self, action: #selector(taped))
view.addGestureRecognizer(tap)
NotificationCenter.default.addObserver(self, selector: #selector(KeyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(KeyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(true)
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
}
#objc func taped(){
self.view.endEditing(true)
}
#objc func KeyboardWillShow(sender: NSNotification){
let keyboardSize : CGSize = ((sender.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue.size)!
if self.view.frame.origin.y == 0{
self.view.frame.origin.y -= keyboardSize.height
}
}
#objc func KeyboardWillHide(sender : NSNotification){
let keyboardSize : CGSize = ((sender.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.size)!
if self.view.frame.origin.y != 0{
self.view.frame.origin.y += keyboardSize.height
}
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}

How to use function to call button instead of pressing it (swift3)

I want to be able to call function start within function use without hitting the action button for start. I know simple thing to do is just put print("a") in use. But I am using this as a simple example because I have a more complex problem in mind.
#IBAction func start(_ sender: Any) {
print("a")}
fun use() {
}
viewdidload() {
use()
}
Consider refactoring your functions. Instead of putting the button action code directly inside of the #IBAction function, put it in a separate function. This way, you can call this code from multiple places.
Here is one solution:
#IBAction func start(_ sender: Any) {
startAction()
}
func startAction() {
print("a")
}
func use() {
startAction()
// anything else
}
override func viewDidLoad() {
use()
}
Create an IBOutlet for your button:
#IBOutlet weak var button: UIButton!
Then simply, use this code to trigger its action:
button.sendActions(for: .touchUpInside)

Why viewDidLayoutSubviews is called twice only on first run?

It's driving me crazy this. Only on first run the viewDidLayoutSubviews is called twice.
Here is the code I'm using:
class CICViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
func addQLabel(qLabel: UILabel, questionString: String, bgrLabel: UILabel) {// some code goes here
}
func makeRoundQButtons(qButtons:[UIButton]) {
// some code goes here
}
func addArrows(numberOfArrows:Int, buttonCurAngle:Double) {//some code goes here
}
func animateButtons(qButtons:[UIButton], buttonCurAngle:Double) {
// some code goes here
}
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
}
func backTapped(sender: UIBarButtonItem) {
navigationController?.popViewControllerAnimated(false)
//some code goes here
}
func restartTapped(sender: UIBarButtonItem) {
navigationController?.popToRootViewControllerAnimated(false)
//some code goes here
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
And in my ViewController I call this :
class OneViewController: CICViewController {
override func viewDidLoad() {
super.viewDidLoad()
//some code goes here
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
print("viewDidLayoutSubviews")
self.makeRoundQButtons(qButtons)
self.animateButtons(qButtons, buttonCurAngle: 2.0)
}
override func viewDidAppear(animated: Bool) {
//nothing goes here
}
}
There is no guarantee as for how many times viewDidLayoutSubviews will be called.
You can find a great discussion in this Stack Overflow post:
When is layoutSubviews called?
I found this article useful. A summary from what it says:
init does not cause layoutSubviews to be called (duh)
addSubview causes layoutSubviews to be called on the view being added, the view it’s being added to (target view), and all the subviews of the target view
setFrame intelligently calls layoutSubviews on the view having it’s frame set only if the size parameter of the frame is different
scrolling a UIScrollView causes layoutSubviews to be called on the scrollView, and it’s superview
rotating a device only calls layoutSubview on the parent view (the responding viewControllers primary view)
removeFromSuperview – layoutSubviews is called on superview only (not show in table)

Need to call super constructor for lifecycle methods in Swift

I've been coding for some years now, and I'm very used to always calling a method's super constructor when overriding it. But recently I've been wondering if it's always necessary... I get that when you override an initialiser you should call super.init(). But in Swift and iOS development, if you override a UIViewController lifecycle method like viewDidLoad() and forget to call super.viewDidLoad(), the compiler dosen't produce any warning or error and the code seems to be compiling fine. So I was wondering if the call is somehow build into the SDK, and if it's even necessary to make (with in mind that we want to make the code as efficient and correct as possible)?
I think you may look here a nice answer.
Apple doesn't restrict you to call super.viewDidLoad(), but it won't be safe to use some view cycle methods and variable before it's call. If you want first to init your own vars or properties for example - I think, it won't be a problem.
Yes, you should always call super.
Here is what I do alwyas
// MARK: - Controller life cycle stack
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
override func viewWillAppear(animated: Bool)
{
super.viewWillAppear(animated)
setupNavigationBar()
}
override func viewDidAppear(animated: Bool)
{
super.viewDidAppear(animated)
}
So, after a while I experienced first hand what might happen if I did not always call super:
Let's say you have two viewControllers
class ViewControllerA: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
self.doSomethingImportant()
}
}
class ViewControllerB: ViewControllerA {
override func viewDidLoad() {
self.doSomethingLessImportant()
}
}
Now you expect that when you push to ViewControllerA it'll call doSomethingImportant(), but in most cases that will not happen, because you forgot to call super.viewDidLoad() in ViewControllerA.

How to hide keyboard in swift on pressing return key?

I am using UITextfied while clicking on textfied keyboard appear but when i pressed the return key, keyboard is not disappearing. I used the following code:
func textFieldShouldReturn(textField: UITextField!) -> Bool // called when 'return' key pressed. return NO to ignore.
{
return true;
}
the method resignfirstresponder is not getting in function.
You can make the app dismiss the keyboard using the following function
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
self.view.endEditing(true)
return false
}
Here is a full example to better illustrate that:
//
// ViewController.swift
//
//
import UIKit
class ViewController: UIViewController, UITextFieldDelegate {
#IBOutlet var myTextField : UITextField
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.myTextField.delegate = self
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
self.view.endEditing(true)
return false
}
}
Code source: http://www.snip2code.com/Snippet/85930/swift-delegate-sample
The return true part of this only tells the text field whether or not it is allowed to return.
You have to manually tell the text field to dismiss the keyboard (or what ever its first responder is), and this is done with resignFirstResponder(), like so:
// Called on 'Return' pressed. Return false to ignore.
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
No Delegate Needed
You can create an action outlet from the UITextField for the "Primary Action Triggered" and resign first responder on the sender parameter passed in:
#IBAction func done(_ sender: UITextField) {
sender.resignFirstResponder()
}
Super simple.
(Thanks to Scott Smith's 60-second video for tipping me off about this: https://youtu.be/v6GrnVQy7iA)
Add UITextFieldDelegate to the class declaration:
class ViewController: UIViewController, UITextFieldDelegate
Connect the textfield or write it programmatically
#IBOutlet weak var userText: UITextField!
set your view controller as the text fields delegate in view did load:
override func viewDidLoad() {
super.viewDidLoad()
self.userText.delegate = self
}
Add the following function
func textFieldShouldReturn(userText: UITextField!) -> Bool {
userText.resignFirstResponder()
return true;
}
with all this your keyboard will begin to dismiss by touching outside the textfield aswell as by pressing return key.
I hate to add the same function to every UIViewController.
By extending UIViewController to support UITextFieldDelegate, you can provide a default behavior of "return pressed".
extension UIViewController: UITextFieldDelegate{
public func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true;
}
}
When you create new UIViewController and UITextField, all you have to do is to write one line code in your UIViewController.
override func viewDidLoad() {
super.viewDidLoad()
textField.delegate = self
}
You can even omit this one line code by hooking delegate in Main.storyboard. (Using "ctrl" and drag from UITextField to UIViewController)
Simple Swift 3 Solution:
Add this function to your view controllers that feature a text field:
#IBAction func textField(_ sender: AnyObject) {
self.view.endEditing(true);
}
Then open up your assistant editor and ensure both your Main.storyboard is on one side of your view and the desired view controller.swift file is on the other. Click on a text field and then select from the right hand side utilities panel 'Show the Connection Inspector' tab. Control drag from the 'Did End on Exit' to the above function in your swift file. Repeat for any other textfield in that scene and link to the same function.
#RSC
for me the critical addition in Xcode Version 6.2 (6C86e) is in override func viewDidLoad()
self.input.delegate = self;
Tried getting it to work with the return key for hours till I found your post, RSC. Thank you!
Also, if you want to hide the keyboard if you touch anywhere else on the screen:
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
self.view.endEditing(true);
}
To get automatic keyboard dismissal, I put this code inside one of the methods of my custom text field's class:
textField.addTarget(nil, action:"firstResponderAction:", forControlEvents:.EditingDidEndOnExit)
Substitute your outlet's name for textField.
Another way of doing this which mostly uses the storyboard and easily allows you to have multiple text fields is:
#IBAction func resignKeyboard(sender: AnyObject) {
sender.resignFirstResponder()
}
Connect all your text fields for that view controller to that action on the Did End On Exit event of each field.
Here's the Swift 3.0 update to peacetype's comment:
textField.addTarget(nil, action:Selector(("firstResponderAction:")), for:.editingDidEndOnExit)
I would sugest to init the Class from RSC:
import Foundation
import UIKit
// Don't forget the delegate!
class ViewController: UIViewController, UITextFieldDelegate {
required init(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
#IBOutlet var myTextField : UITextField?
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.myTextField.delegate = self;
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func textFieldShouldReturn(textField: UITextField!) -> Bool {
self.view.endEditing(true);
return false;
}
}
When the user taps the Done button on the text keyboard, a Did End On Exit event will be generated; at that time, we need to tell the text field to give up control so that the keyboard will go away. In order to do that, we need to add an action method to our controller class.
Select ViewController.swift add the following action method:
#IBAction func textFieldDoneEditing(sender: UITextField) {
sender.resignFirstResponder()}
Select Main.storyboard in the Project Navigator and bring up the connections inspector. Drag from the circle next to Did End On Exit to the yellow View Controller icon in the storyboard and let go. A small pop-up menu will appear containing the name of a single action, the one we just added. Click the textFieldDoneEditing action to select it and that's it.
Swift 3
Add this code below to your VC
//hide keyboard when user tapps on return key on the keyboard
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
self.view.endEditing(true);
return false;
}
Works for me
override func viewDidLoad() {
super.viewDidLoad()
let tap = UITapGestureRecognizer(target: self, action: #selector(handleScreenTap(sender:)))
self.view.addGestureRecognizer(tap)}
then you use this function
func handleScreenTap(sender: UITapGestureRecognizer) {
self.view.endEditing(true)
}
Swift
Using optional function from UITextFieldDelegate.
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.endEditing(false)
}
false means that field can be ask to resign. true – force resign.
Make sure that your textField delegate is set to the view controller from which you are writing your textfield related code in.
self.textField.delegate = self
you can put this anywhere but not in a UIButton
func TextFieldEndEditing(text fiend name: UITextField!) -> Bool
{
return (false)
}
then you can put this code in a button(also for example):
self.view.endEditing(true)
this worked for me
In the view controller you are using:
//suppose you are using the textfield label as this
#IBOutlet weak var emailLabel: UITextField!
#IBOutlet weak var passwordLabel: UITextField!
//then your viewdidload should have the code like this
override func viewDidLoad() {
super.viewDidLoad()
self.emailLabel.delegate = self
self.passwordLabel.delegate = self
}
//then you should implement the func named textFieldShouldReturn
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
// -- then, further if you want to close the keyboard when pressed somewhere else on the screen you can implement the following method too:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
self.view.endEditing(true);
}
you should connect the UITextfied with a delegate of view controller to make this function called
All in One Hide Keyboard and Move View on Keyboard Open: Swift 5
override func viewDidLoad() {
super.viewDidLoad()
let tap = UITapGestureRecognizer(target: self, action: #selector(taped))
view.addGestureRecognizer(tap)
NotificationCenter.default.addObserver(self, selector: #selector(KeyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(KeyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(true)
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
}
#objc func taped(){
self.view.endEditing(true)
}
#objc func KeyboardWillShow(sender: NSNotification){
let keyboardSize : CGSize = ((sender.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue.size)!
if self.view.frame.origin.y == 0{
self.view.frame.origin.y -= keyboardSize.height
}
}
#objc func KeyboardWillHide(sender : NSNotification){
let keyboardSize : CGSize = ((sender.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.size)!
if self.view.frame.origin.y != 0{
self.view.frame.origin.y += keyboardSize.height
}
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}

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