Is this a good way to show a view by touch a button at the middle of the navigation bar and remove it by touch anywhere else? - ios

Question

I'm trying to put a button at the middle of the navigation bar, it will show a list when I touch it (I added a pure UIView here instead of a UITabeView to just make the code simpler) . And then the additional view will be removed when I touch anywhere else. So I add a background view whose size is the same as the screen to response my touch. Although it still behind the navigation bar.
Here is my question:
Is this a good implementation?
class ViewController: UIViewController {
var optionView: UIView!
var backgroundView: UIView!
override func viewDidLoad() {
super.viewDidLoad()
let button = UIButton(type: .system)
button.addTarget(self, action: #selector(ViewController.titleButtonTapped), for: .touchUpInside)
button.frame = CGRect(x: 0, y: 0, width: 20, height: 30)
button.backgroundColor = .red
navigationItem.titleView = button
}
func titleButtonTapped() {
backgroundView = UIView(frame: UIScreen.main.bounds)
backgroundView.backgroundColor = .clear
let gesture = UITapGestureRecognizer(target: self, action: #selector(ViewController.handleGesture)) // add this gesture to response my touch
backgroundView.addGestureRecognizer(gesture)
view.addSubview(maskView)
optionView = UIView(frame: CGRect(x: -40, y: 30, width: 100, height: 100)) // x = button.wdith / 2 - optionView.width / 2
optionView.backgroundColor = .red
navigationItem.titleView?.addSubview(alertView)
}
func handleGesture() {
optionView.removeFromSuperview()
backgroundView.removeFromSuperview()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Now it looks like the following.
Edit:
The following is my implementation of a popover view.
func buttonTapped() {
let popoverViewController = UIViewController()
popoverViewController.preferredContentSize = CGSize(width: 300, height: 300)
popoverViewController.modalPresentationStyle = .popover
let presentationController = popoverViewController.popoverPresentationController!
presentationController.delegate = self
presentationController.sourceView = view
presentationController.sourceRect = CGRect(x: 100, y: 100 , width: 100, height: 100)
present(popoverViewController, animated: true, completion: nil)
}
// delegate
func adaptivePresentationStyle(for controller: UIPresentationController) -> UIModalPresentationStyle {
return .none
}
It's a little bit different frrom the Apple documentation. They recommended that we'd better configure the presentation controller after calling present(:animated: completion:) method. But it doesn't work if I don't configure it before presentation. Maybe, because I set the delegate.
Configuring the popover presentation controller after calling present(_:animated:completion:) might seem counter-intuitive but UIKit does not create a presentation controller until after you initiate a presentation. In addition, UIKit must wait until the next update cycle to display new content onscreen anyway. That delay gives you time to configure the presentation controller for your popover.

Answer 1

For using a popover or not, it depends on the purpose of this pop over view. If it has lots of information, it will be better to separate it out to another view controller and make segue to it on button click. This will provides user the full screen to look at whatever it is.
For me, adding a button at the center of a navigation bar is not usual. You have to inform me about it for me to click on it.
In conclusion:
If you want a popover view to tell user hints or show them something, it will be better to use UIPopoverPresentationController so that you don't need to care about the styles.
If you want another view to show data, list of pictures etc, it will be better to use a segmented control or another view controller

Answer 2

var optionView: UIView!
var backgroundView: UIView!
override func viewDidLoad()
{
super.viewDidLoad()
self.view.backgroundColor = UIColor.white
let button = UIButton(type: .system)
button.addTarget(self, action: #selector(ViewController.titleButtonTapped), for: .touchUpInside)
button.frame = CGRect(x: 0, y: 0, width: 20, height: 30)
button.backgroundColor = .red
navigationItem.titleView = button
}
func titleButtonTapped()
{
if backgroundView == nil
{
backgroundView = UIView(frame: UIScreen.main.bounds)
backgroundView.backgroundColor = .clear
let gesture = UITapGestureRecognizer(target: self, action: #selector(ViewController.handleGesture)) // add this gesture to response my touch
backgroundView.addGestureRecognizer(gesture)
view.addSubview(backgroundView)
}
if optionView == nil
{
optionView = UIView(frame: CGRect(x: -40, y: 30, width: 100, height: 100)) // x = button.wdith / 2 - optionView.width / 2
optionView.backgroundColor = .red
navigationItem.titleView?.addSubview(optionView)
}
}
func handleGesture()
{
if optionView != nil
{
optionView.removeFromSuperview()
optionView = nil
}
if backgroundView != nil
{
backgroundView.removeFromSuperview()
backgroundView = nil
}
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
}