Swift - access UIImagePickerController from modal view - ios

Is there a way to present an UIImagePickerController from inside a modal view?
In my case I have a class called MakeWishView which is a UIView and the user should be able to pick an image if he taps on a button inside the MakeWishView. My problem right now is that I can not call present because MakeWishView is not a ViewController but a UIView.
This is what I would like to call:
#objc private func wishImageButtonTapped(){
showImagePickerController()
print("wishImageButtonTapped")
}
// image picker
extension MakeWishView: UIImagePickerControllerDelegate, UINavigationControllerDelegate {
#objc func showImagePickerController(){
let imagePickerController = UIImagePickerController()
imagePickerController.delegate = self
present(imagePickerController, animated: true, completion: nil) // -> error
}
}

Add a delegate to the presenting vc like
class MakeWishView:UIView {
weak var delegate:VCName?
or
let root = (UIApplication.shared.delegate as! AppDelegate).window!.rootViewController
root.present(imagePickerController, animated: true, completion: nil)

Related

UICollectionView Protocol Issue

I have a viewController that presents a 'CollectionViewController', via an action button.
#objc func addPhoto() {
let layout = UICollectionViewFlowLayout()
let photoController = UINavigationController(rootViewController: PhotoController(collectionViewLayout: layout))
present(photoController, animated: true, completion: nil)
}
Inside the 'PhotoController', I'm trying to pass data back from this controller to the original viewController using the standard protocol procedure.
protocol PhotoControllerDelegate {
func store(image: UIImage)
}
var delegate: PhotoControllerDelegate?
#objc func handleSave() {
if let image = headerImage {
delegate?.store(image: image)
}
///Dimiss viewController
dismiss(animated: true, completion: nil)
}
Now back inside the original viewController, I have re-instantiated the dismissed PhotoController:
let photoController = PhotoController()
and assigned the delegate inside viewDidLoad()
photoController.delegate = self
then provided the delegate method inside the original viewController:
func store(image: UIImage) {
selectedPhotoImage.image = image
}
Issue is: this method is not even being called.
I usually don't have any issues however this one has stumped me.
Any help would be great.
P.S. My viewControllers have a lot of extra junk inside, so couldn't post the complete code.
Make sure to add delegate as self to receive protocol event in that viewController
#objc func addPhoto() {
let layout = UICollectionViewFlowLayout()
let objVC = PhotoController(collectionViewLayout: layout)
objVC.delegate = self
let photoController = UINavigationController(rootViewController: objVC)
present(photoController, animated: true, completion: nil)
}
Don't forget to add delegate in same viewController. Use extension to make it clean code.
extension SourceController: PhotoControllerDelegate {
func store(image: UIImage) {
selectedPhotoImage.image = image
}
}
Define protocol like below in PhotoController
public protocol PhotoControllerDelegate {
func store(image: UIImage)
}

Can UIImagePickerController be used directly on story board?

I have an impression that ViewController usage are similar: on story board, we drag an UIViewController onto scene, then change its class type, e.g. to UIImagePickerController. (I want to make a dedicated scene for picking images)
But later I find that UIImagePickerController won't work if I directly subclass:
class TestUIImagePickerController: UIImagePickerController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
self.sourceType = .photoLibrary
self.delegate = self
// self.present(self, animated: true) // either comment it out or not, both way won't work.
}
But it works only if I put an UIViewController on storyboard, then construct an UIImagePickerController programmatically:
class SecondTestUIImagePickerController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let picker = UIImagePickerController()
picker.sourceType = .photoLibrary
picker.delegate = self
self.present(picker, animated: true)
}
May I know whether I missed anything in the first usage example? And is it a must to create UIImagePickerController programmatically then present it via an agent view controller (UIVIewController)?
self.present(self, animated: true)
you can not self present self, use another ViewController to present UIImagePickerController
UIImagePickerController can be used on Story board, in your code, for example
class SecondTestUIImagePickerController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let sb = UIStoryboard(name: "ImagePickerStoryboard", bundle: nil)
let picker = sb.instantiateViewControllerWithIdentifier("ImagePicker") as! TestUIImagePickerController
self.present(picker, animated: true)
}
keep in mind that UIImagePickerController is subclass of UINavigationController

Show second modal view controller after first was closed

I have two view controller that opens modally. When the first VC closed then the second should be opened. But when I close the first one, the second one is not displayed at all.
what is the problem?
My code is:
self.dismiss(animated: true) {
let flowVC = LanguageFlowViewController()
self.present(flowVC, animated: true)
}
You need reference of view controller from where you to present first view controller.
For example, you have view controller name as X, from there your first view controller A present. So you need reference of X to present B, because A will not be available in memory.
So when you try to present second view controller using self, it will do nothing.
So, for solution assign reference of X view controller to A. In class A, declare:
var refX: X?
While present A from X, set self to refX. Like:
var aVC = A() // This is temp, you need to instantiate your view controller here.
aVC.refX = self
self.present(aVC, animated: true, completion: nil)
Now, inside view controller A, when dismiss:
var bVC = B() // This is temp, you need to instantiate your view controller here.
self.dismiss(animated: true) {
if self.refX != nil {
self.refX?.present(bVC, animated: true, completion: nil)
}
}
I hope this will help you.
If you want to open modally ThirdViewController after Dismiss SecondViewController then you have to create protocol for it.
Like we have three UIViewController(FirstViewController,SecondViewController and
ThirdViewController)
Step 1: We need to create a protocol in SecondViewController as given below code.
protocol DismissedViewProtocal {
func dismissView()
}
class SecondViewController: UIViewController {
var delegate: DismissedViewProtocal?
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
#IBAction func dismissSecondViewAction(_sender : AnyObject) {
dismiss(animated: true) {
self.delegate?.dismissView()
}
}
Step 2: You need to add protocol in FirstViewController as given below
class FirstViewController: UIViewController, DismissedViewProtocal {
override func viewDidLoad() {
super.viewDidLoad()
}
#IBAction func anAction(_sender : AnyObject){
let flowVC = self.storyboard?.instantiateViewController(withIdentifier:"SecondViewController") as? SecondViewController
secondVC?.delegate = self
self.present(secondVC!, animated: true) {
}
}
func dismissView() {
let thirdVC = self.storyboard?.instantiateViewController(withIdentifier:"ThirdViewController")
self.present(thirdVC!, animated: true) {
}
}
}
Your are dismissing the current view controller by calling self.dismiss().
Therefore it is impossible for it to present anything anymore, since it is removed from the view hierarchy. As others have mentioned, try using the self.presentingViewController or self.navigationController (if it is on a navigationController) to present your new view.
However, if you need maximum flexibility create a delegate protocol. Create a protocol with a function presentForChild(viewController: UIViewController). Before your previous view presents the view from which the code in your question belongs to, give it a reference of the protocol.
Example:
protocol ChildPresentDelegate: class {
func presentForChild(vc: UIViewController)
}
class FirstController: UIViewController, ChildPresentDelegate {
func presentForChild(vc: UIViewController) {
present(vc, animated: true, completion: nil)
}
/**
other code
*/
func showControllerAsWasShownInTheQuestion() {
let controller = SecondController()
controller.delegate = self
present(controller, animated: true, completion: nil)
}
}
class SecondController: UIViewController {
weak var delegate: ChildPresentDelegate?
func dismissMySelf() {
self.dismiss(animated: true) {
delegate?.presentForChild(vc: LanguageFlowViewController())
}
}
}

PresentViewController does not work: view is not in the window hierarchy in TabBarController

I have created a CustomAlertView.
protocol CustomAlertViewControllerDelegate{
func retryToFetchData()
}
class CustomAlertViewController: UIViewController {
#IBOutlet weak var alertView: UIView!
var delegate: CustomAlertViewControllerDelegate!
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.alertView.alpha = 0
self.alertView.frame.origin.y = self.alertView.frame.origin.y + 50
UIView.animate(withDuration: 0.4) {
self.alertView.alpha = 1.0
self.alertView.frame.origin.y = self.alertView.frame.origin.y - 50
}
}
#IBAction func retryButton(_ sender: UIButton) {
delegate?.retryToFetchData()
self.dismiss(animated: true, completion: nil)
}
}
I have created a static function to show that view. The view is just a UIViewController that will have a child View which will act as a popUP, with a transparent background.
func showErrorBox(view: UIViewController, message: String, delegate: CustomAlertViewControllerDelegate){
let customAlert = view.storyboard?.instantiateViewController(withIdentifier: "customAlertViewController") as! CustomAlertViewController
customAlert.providesPresentationContextTransitionStyle = true
customAlert.definesPresentationContext = true
customAlert.modalPresentationStyle = UIModalPresentationStyle.overCurrentContext
customAlert.modalTransitionStyle = UIModalTransitionStyle.crossDissolve
customAlert.delegate = delegate
view.present(customAlert, animated: true, completion: nil)
}
Now, I am calling this VC anywhere I needed to show a popUP with showErrorBox(view: self, message: message, delegate: self) now my issue is I need to show this popup in a ViewController which is inside of a TabBarController, when I change the view between the UITabBar, and try pressing the reload button, the app throws an error,
presentViewController does not work: view is not in the window
hierarchy
Edit:
There is a Retry button on the ErrorBox(popUp). The error happens only when the error box is loaded and I changed the view to different tab and then hit the reload button. In normal scenario like, hitting the reload button when I am in the same page works fine.
I am not sure of issue, but it has something to do with when I change the view between tabs when the error box is present.
try self.present(customAlert, animated: true, completion: nil) instead view.present(customAlert, animated: true, completion: nil). If I understand your problem, should works
Solution,
The problem was, when I changed the views in TabController the reference to the customAlertView was removed from the window hierarchy. So, As soon as I leave the TabView which was loading the CustomAlertView need to be removed.
So to solve the issue, I have added following code in CustomAlertViewController
override func viewWillDisappear(_ animated: Bool) {
super. viewWillDisappear(animated)
self.dismiss(animated: true, completion: nil)
}
Try to getting the TopMost ViewController and presenting CustomAlertViewController from it instead of "self".
refer this link to :
GetTopMostViewController

UIPageViewController + UIImagePicker with custom controls not working - view is not in window hierarchy

I'm trying to create effect similar to Snapchat in Swift - swiping between UIImagePicker with custom controls and other VCs.
The problem is:
when CameraVC is presented for the first time background is black and swipe between VCs works only on controls (on empty space where should be image from camera it isn't) and warning shows up "Attempt to present UIImagePickerController on CameraVC whose view is not in the window hierarchy!"
when I swipe to another VC and then back to CameraVC UIImagePicker is presented properly and everything works great instead of swiping between VCs which is not working at all. There's also no "window hierarchy" warning
So I think the reason why it's not working is that UIImagePicker is presenting over PageViewController not "in" it, but I have no idea how to fix this.
I'm presenting PageViewController like this:
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
let storyboard = UIStoryboard(name: "Main", bundle: nil)
var vcPageView = storyboard.instantiateViewControllerWithIdentifier("PageViewID") as! UIViewController
self.presentViewController(vcPageView, animated: false, completion: nil)
}
Loading VCs to table in PageViewController:
override func viewDidLoad() {
super.viewDidLoad()
self.delegate = self
self.dataSource = self
let storyboard = UIStoryboard(name: "Main", bundle: nil)
var vc0 = storyboard.instantiateViewControllerWithIdentifier("CameraID") as! UIViewController
var vc1 = storyboard.instantiateViewControllerWithIdentifier("vc2ID") as! UIViewController
self.myViewControllers = [vc0, vc1]
self.setViewControllers([myViewControllers[0]], direction: UIPageViewControllerNavigationDirection.Forward, animated: false, completion: nil)
}
And finally CameraVC:
#IBOutlet var cameraOverlay: UIView!
var camera = UIImagePickerController()
override func viewDidLoad() {
super.viewDidLoad()
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.Camera){
self.camera.delegate = self
self.camera.sourceType = UIImagePickerControllerSourceType.Camera;
self.camera.mediaTypes = [kUTTypeImage]
self.camera.allowsEditing = false
self.camera.showsCameraControls = false
self.cameraOverlay.frame = self.camera.cameraOverlayView!.frame
self.cameraOverlay.bringSubviewToFront(self.cameraOverlay)
self.camera.cameraOverlayView = self.cameraOverlay
self.cameraOverlay = nil
}
}
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
self.topMostViewController().presentViewController(self.camera, animated: false, completion: nil)
}
topMostViewController code:
extension UIViewController {
func topMostViewController() -> UIViewController {
// Handling Modal views
if let presentedViewController = self.presentedViewController {
return presentedViewController.topMostViewController()
}
// Handling UIViewController's added as subviews to some other views.
else {
for view in self.view.subviews
{
// Key property which most of us are unaware of / rarely use.
if let subViewController = view.nextResponder() {
if subViewController is UIViewController {
let viewController = subViewController as! UIViewController
return viewController.topMostViewController()
}
}
}
return self
}
}
Try this, In the CameraVC move the camera code in the viewDidLoad() to the viewDidAppear()

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