Swift: Cannot click button in subview - ios

I have a ViewController, LockScreenVC, and am adding a UIView to it.
In that UIView, I am adding a UIButton. The button shows up, but I cannot click the button. If I add the button instead to the LockScreenVC, I can click the button - but it is no longer part of the UIView.
I've tried setting isUserInteractionEnabled to true, but that has not done anything.
import UIKit
class LockScreenVC: UIViewController {
lazy var detailContainer : UIView = {
let v = UIView();
v.backgroundColor = UIColor.black.withAlphaComponent(0.2)
return v
}()
lazy var detailButton: UIButton = {
let btn = UIButton(frame: CGRect(x: 10, y: 10, width: 300, height: 150))
btn.setTitle("Click Me", for: .normal)
return btn
}()
override func viewDidLoad() {
super.viewDidLoad()
detailButton.addTarget(self, action: #selector(onDetailButtonPressed), for: .touchUpInside)
detailContainer.addSubview(detailButton)
detailContainer.isUserInteractionEnabled = true
view.addSubview(detailContainer)
}
#objc func onDetailButtonPressed() {
print("You pressed the button!")
}
}

Your detailContainer has zero frame. Please set frame for it

Related

Create UIButton on top layer UITableViewController like as AirBnB

How to create UIButton in UITableViewController like as AirBnB map.
Highlighted in red in screenshot.
It's quite easy actually, just create the table view as you always do (either storyboard or code) then create the button, position it correctly, set constraints and make sure it's not a subview of the table view but the view that contains the table view.
Since you didn't specify whether you use the storyboard or not, I did use it for the example below.
See this extremely simple demo I've just created:
This is the view hierarchy:
And these are the constraints for the button:
Create a button first and then then override the function scrollViewDidScroll():
import UIKit
class YourTableViewController: UITableViewController {
private let button = UIButton(type: UIButton.ButtonType.custom) as UIButton
override func viewDidLoad() {
let image = UIImage(named: "Image.png")
button.frame = CGRect(x: yourXpos, y: yourYPos, width: 60, height: 60)
button.setImage(image, for: .normal)
button.clipsToBounds = true
button.layer.cornerRadius = 30
button.addTarget(self, action: #selector(buttonClicked(_:)), for:.touchUpInside)
areaOfTableView.addSubview(button)
}
override func scrollViewDidScroll(_ scrollView: UIScrollView) {
let offset = self.areaOfTableView.contentOffset.y
button.frame = CGRect(x: yourXpos, y: offset + yourYpos, width: btn.frame.size.width, height: btn.frame.size.height)
}
#objc private func buttonClicked(_ button: UIButton) {
// Action when you tapped the button
}
}

Trying to call a navigation bar function in another class pragmatically

I created a navigation bar which I'm trying to call in another view controller. I set it up by calling the methods which I separated into left, center and right buttons. In my other controller I call the navbarcontroller and try and call the method for which i setup the navigation toolbar. Nothing happens, however there is no crash.
import UIKit
class NavBarController : UIViewController{
var screenSize: CGRect!
override func viewDidLoad() {
super.viewDidLoad()
setupNavigationBarItems()
setupToolBarItems()
self.navigationController?.isToolbarHidden = false
self.view!.backgroundColor = .white
}
and my method for the navigation bar is this
func setupNavigationBarItems() {
setupCenterNavButton()
setupLeftNavButton()
setupRightNavButton()
}
func showCalendarController() {
let navController = CalendarController()
self.present(navController, animated: true, completion: nil)
} //connect bottom bar buttons to controller
func showEventsController() {
let navController = EventsController()
self.present(navController, animated: true, completion: nil)
} //connect bottom bar buttons to controller
func setupNavigationBarItems() {
setupCenterNavButton()
setupLeftNavButton()
setupRightNavButton()
} // top bar button setup
private func setupCenterNavButton() {
let buttonFrame = UIView(frame: CGRect(x: 0, y: 0, width: 165,
height: 20))
mainFeedButton.frame = CGRect(x: 0,y: 0, width: 80,height: 20) as
CGRect
mainFeedButton.backgroundColor = UIColor.blue
peekFeedButton.frame = CGRect(x: 85,y: 0, width: 80,height: 20) as
CGRect
peekFeedButton.backgroundColor = UIColor.blue
buttonFrame.addSubview(mainFeedButton)
buttonFrame.addSubview(peekFeedButton)
navigationItem.titleView = buttonFrame
} //center bar buttons / action setup
private func setupLeftNavButton() {
navigationItem.leftBarButtonItem = UIBarButtonItem(customView:
favoriteButton)
}// left bar buttons / action setup
private func setupRightNavButton() {
navigationItem.rightBarButtonItem = UIBarButtonItem(customView:
moreButton)
} //right bar buttons / action setup
lazy var mainFeedButton: UIButton! = {
let button = UIButton(type: .custom) // button type
button.setTitle("Main",for: .normal) //button title
button.sizeToFit() // size button to fit the title
var frame = button.frame //create frame to manipulate the body
button.frame = CGRect(x: 0, y: 0, width: 100, height: 40)
button.addTarget(self, action:
#selector(self.showMainFeedController),
for: .touchUpInside)
return button
}() //mainFeed button connected to Feed Controller
lazy var peekFeedButton: UIButton! = {
let button = UIButton(type: .custom) //button type
button.setTitle("Spy",for: .normal) //button title
button.sizeToFit() // size button to fit the title
var frame = button.frame //create frame to manipulate the body
button.frame = CGRect(x: 20, y: 0, width: 100, height: 40)
button.addTarget(self, action:
#selector(self.showSpyFeedController),
for: .touchUpInside)
return button
}()//peekFeed button frame and action setup
lazy var favoriteButton: UIButton! = {
let button = UIButton(type: .system) //default button with blue
text
button.setImage(#imageLiteral(resourceName:
"star").withRenderingMode(.alwaysOriginal), for: .normal)
button.contentMode = .scaleAspectFit
button.frame = CGRect(x: 0, y: 0, width: 24, height: 24)
button.addTarget(self, action: #selector(favoriteButton_tapped),
for: .touchUpInside)
return button
}() //favorites button frame and action setup
lazy var moreButton: UIButton! = {
let button = UIButton(type: .system) //default button with blue
text
button.setImage(#imageLiteral(resourceName:
"more").withRenderingMode(.alwaysOriginal), for: .normal)
button.contentMode = .scaleAspectFit
button.frame = CGRect(x: 0, y: 0, width: 24, height: 24)
button.addTarget(self, action: #selector(moreButton_tapped),
for: .touchUpInside)
return button
}() //more button frame and action setup
func showMainFeedController() {
let navController = MainFeedController()
self.present(navController, animated: true, completion: nil)
} //mainFeed button connected to Feed Controller
func showSpyFeedController() {
let navController = SpyFeedController()
self.present(navController, animated: true, completion: nil)
}//peekFeed button connected to SpyFeedController
func favoriteButton_tapped(sender: UIButton) {
print("You touched this!")
}
func moreButton_tapped(sender: UIButton) {
print("You touched this!")
}
}
I then try and call the function by setupNavigationBarItems() like this
import UIKit
class EventsController: UIViewController{
override func viewDidLoad() {
super.viewDidLoad()
let navbar = NavBarController()
navbar.setupNavigationBarItems()
self.navigationController?.isToolbarHidden = false
self.view.backgroundColor = .white
}
}
I'm not sure if this a valid way. I'm still kinda new to all of this.
It's not clear what you expect to happen, but here's what does happen:
let navbar = NavBarController()
A completely new NavBarController object is created.
navbar.setupNavigationBarItems()
That NavBarController object's setupNavigationBarItems is called.
self.navigationController?.isToolbarHidden = false
self.view.backgroundColor = .white
Your code comes to an end. navbar was a local variable, so the NavBarController object vanishes in a puff of smoke. The end. This object was created and configured to no purpose.
I remember my first month in iOS way back 2015 :D, didn't have any knowledge in OOP, I didn't know too how to pass a data to another screen or class.
Anyways, you DO NOT create a new instance of your NavBarController class in your EventsController. If you want to talk to your NavBarController from your EventsController, then you will need a reference that is currently alive. You can also use delegate (search for that later).
So before you show or present your EventsController from your NavBarController, pass your current NavBarController instance to the next screen which is EventsController. BUT FIRST, you need to declare a variable in your EventsController, correct? :)
Declare a variable with a type of NavBarController inside your EventsController class, like so:
var navBarController: NavBarController!
Then in this piece of code of yours, pass your self (the NavBarController instance) to the EventsController class before showing or presenting, take note that you mistakenly gave a wrong name to your EventsController new instance, so I renamed it:
func showEventsController() {
let eventsController = EventsController()
eventsController.navBarController = self // THIS :)
self.present(eventsController, animated: true, completion: nil)
}
Lastly, instead of this:
let navbar = NavBarController()
navbar.setupNavigationBarItems()
Make use of your declared variable, like so:
self.navBarController.navbar.setupNavigationBarItems()
Hope this helps! :)

How can I get events to my (sub) UIView?

I'm new to Swift and have a hard time understand the event flow. The code below can be run directly in an xcode playground. I have a white UIView in the background. This view has a brown button and a red view as sub-views. Click on them and the events are logged in the controller, just as expected.
But the controller of this white view also adds another view, that has it's own controller class (SubviewController). SubviewController is green and has a blue subview with a black button. Question is... why don't I get any logs from the green, blue and black views/buttons?
import Foundation
import UIKit
import PlaygroundSupport
class TestViewController : UIViewController {
let playButton: UIButton = {
let playButton = UIButton(frame: CGRect(x: 155, y: 135, width: 160, height: 40))
playButton.setTitle("BROWN BUTTON", for: .normal)
playButton.backgroundColor = UIColor.brown
return playButton
}()
override func loadView() {
let viewWhite = UIView()
viewWhite.backgroundColor = UIColor.white
let viewRed = UIView()
viewRed.backgroundColor = UIColor.red
viewRed.frame = CGRect(x: 20, y: 20, width: 40, height: 10)
viewRed.clipsToBounds = true
let recognizer2 = UITapGestureRecognizer(target: self, action: #selector (self.handleTapRed(_:)))
viewRed.addGestureRecognizer(recognizer2)
let recognizer = UITapGestureRecognizer(target: self, action: #selector (self.handleTap(_:)))
viewWhite.addGestureRecognizer(recognizer)
playButton.addTarget(self, action: #selector (self.action) , for: .touchUpInside)
let catList = SubviewController()
viewWhite.addSubview(catList.view)
viewWhite.addSubview(playButton)
viewWhite.addSubview(viewRed)
self.view = viewWhite
}
func action() {
print("Brown button tapped")
}
func handleTap(_ sender:UITapGestureRecognizer){
print("WHITE VIEW (background view) TAPPED")
}
func handleTapRed(_ sender:UITapGestureRecognizer){
print("RED VIEW TAPPED")
}
}
class SubviewController: UIViewController {
let buttonBlack: UIButton = {
let button = UIButton(frame: CGRect(x: 40, y: 10, width: 170, height: 20))
button.backgroundColor = UIColor.black
button.setTitle("BLACK BUTTON", for: .normal)
return button
}()
let viewBlue: UIView = {
let v = UIView()
v.backgroundColor = UIColor.blue
v.frame = CGRect(x: 20, y: 40, width: 240, height: 60)
v.clipsToBounds = true
return v
}()
override func loadView() {
super.loadView()
self.view.backgroundColor = UIColor.green
buttonBlack.addTarget(self, action: #selector (self.blackKlick) , for: .touchUpInside)
self.view.addSubview(viewBlue)
self.view.frame = CGRect(x: 0, y: 40, width: 240, height: 60)
self.view.clipsToBounds = true
self.view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector (self.handleTapGreen(_:))))
viewBlue.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector (self.handleTapBlue(_:))))
viewBlue.addSubview(buttonBlack)
}
func blackKlick() {
print("Black button tapped")
}
func handleTapBlue(_ sender:UITapGestureRecognizer){
print("BLUE VIEW TAPPED")
}
func handleTapGreen(_ sender:UITapGestureRecognizer){
print("GREEN VIEW TAPPED")
}
}
PlaygroundPage.current.liveView = TestViewController()
Thanks for any help!
This line in your current code:
let catList = SubviewController()
creates a local instance of SubvieController. As soon as you exit the loadView() func, that instance is gone.
So, you need a class-level variable to keep that instance around. Add this line:
class TestViewController : UIViewController {
var catList: SubviewController!
and then remove the let from the instantiation line in loadView():
catList = SubviewController()

Swift: Calling UIButton press from another class

I have my ViewController.class and a Menu.class
In the Menu.class I create and setup all the buttons and in the ViewController.class I add the Menu to the view. When I run the code everything is shown on the screen but I am not able to press the button.
This is how my ViewController looks like:
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let menu = Menu()
menu.setupView(controller: self, width: 600, height: 120)
self.view.addSubview(menu)
// Do any additional setup after loading the view, typically from a nib.
}
}
And this is my Menu:
import Foundation
import UIKit
class Menu: UIView{
func setupView(controller: ViewController, width: CGFloat, height: CGFloat){
let newGame = UIButton(frame: CGRect(x: controller.view.center.x, y: 300, width: width, height: height))
newGame.center = CGPoint(x: controller.view.center.x, y: 300)
newGame.setTitle("New Game", for: .normal)
newGame.backgroundColor = UIColor.gray
newGame.titleLabel?.font = UIFont(name: "Helvetica", size: 42)
newGame.setTitleColor(UIColor.black, for: .normal)
newGame.addTarget(self, action: #selector(Menu.newGame), for: .touchUpInside)
self.addSubview(newGame)
}
func newGame(){
print("New Game")
}
}
What is my mistake. Do I need to do more initializing so it is able to detect a press?
This is how you should do it. Repeat the operation for buttonTwo and label. Setup the view in viewDidLoad() and setup the frames in viewDidLayoutSubviews.
If you subclass any UIView you should setup the frames in layoutSubviews()
If you want to display a tableView when you click on newGame then create a new UIViewController. Add a UITableView in it, the same way you did add Button and Label in ViewController
import UIKit
class ViewController: UIViewController {
let buttonOne = UIButton()
let buttonTwo = UIButton()
let label = UILabel()
override func viewDidLoad() {
super.viewDidLoad()
buttonOne.backgroundColor = UIColor.gray
buttonOne.setTitle("New Game", for: .normal)
buttonOne.titleLabel?.font = UIFont(name: "Helvetica", size: 42)
buttonOne.setTitleColor(UIColor.black, for: .normal)
buttonOne.addTarget(self, action: #selector(newGame), for: .touchUpInside)
view.addSubview(buttonOne)
view.addSubview(buttonTwo)
view.addSubview(label)
}
override func viewDidLayoutSubviews() {
buttonOne.frame = CGRect(x: 0, y: 300, width: 600, height: 120)
buttonOne.center.x = self.view.center.x
}
func newGame(sender: UIButton?) {
print("New Game")
}
}

Anchor the bottom of my tableview to the top of my container view

I was searching about how can I anchor the bottom of my tableview to the top of my container view, which is in the bottom of my view, so when I press the textfield, the container view shows up, which has a textfield and a button. But how can I see the bottom of my tableview while I'm writing a message in the container view? Something like scroll automatically to the bottom of the tableview when the container with the textfield and the button shows up, so I can see the last cells.
Here is the code of the container view:
lazy var inputTextField: UITextField = {
let textField = UITextField()
textField.placeholder = "Enter message..."
textField.translatesAutoresizingMaskIntoConstraints = false
textField.delegate = self
textField.frame.size.width = 150.0
return textField
}()
lazy var sendButton: UIButton = {
let boton = UIButton(type: .System)
boton.setTitle("Delete", forState: .Normal)
boton.translatesAutoresizingMaskIntoConstraints = false
boton.addTarget(self, action: #selector(handleSend), forControlEvents: .TouchUpInside)
return boton
}()
// MARK: container
lazy var inputContainerView: UIView = {
let containerView = UIView()
containerView.frame = CGRect(x: 0, y: 0, width: self.view.frame.width, height: 50)
containerView.backgroundColor = UIColor.whiteColor()
containerView.addSubview(self.inputTextField)
containerView.addSubview(self.sendButton)
//I added some constrains to the textfield and the button
return containerView
Also I have this methods:
override var inputAccessoryView: UIView? {
get {
return inputContainerView
}
}
override func canBecomeFirstResponder() -> Bool {
return true
}
So, how can I do it?
Set the tableView's contentInset.bottom property to the given height of the container view, then:
tableView.layoutIfNeeded()
tableView.setContentOffset(CGPoint(x: 0, y: tableView.contentSize.height-tableView.frame.height+tableView.contentInset.bottom), animated: true)
...to force it to scroll to the bottom.

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