Passing image from ViewController to ViewController - ios

Question

I try to pass an image from one ViewController1 to another ViewController2 when a button is tapped. I am using segues in my Storyboard.
ViewController1
import UIKit
class ViewController: UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate {
var imagePicker: UIImagePickerController!
#IBAction func editPhoto(_ sender: UIButton) {
let editViewController = storyboard?.instantiateViewController(withIdentifier: "EditImageViewController") as! EditImageViewController
editViewController.imageForEdit = imageView.image!
print(imageView)
print(imageView.image!)
navigationController?.pushViewController(editViewController, animated: true)
}
#IBOutlet weak var imageView: UIImageView! {
didSet {
imageView.contentMode = .scaleAspectFill
imageView.clipsToBounds = true
}
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
print(imageView) results in
some(UIImageView: 0x7fc34df0e630; frame = (8 29; 303 443); clipsToBounds = YES; opaque = NO; autoresize = RM+BM; userInteractionEnabled = NO; layer = CALayer: 0x60000023e520)
and print(imageView.image!) in
size {3000, 2002} orientation 0 scale 1.000000
ViewController2
import UIKit
class EditImageViewController: UIViewController {
var imageForEdit = UIImage()
#IBOutlet weak var editingImage: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
editingImage.image = imageForEdit
print(imageForEdit)
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
print(imageForEdit) results in
size {0, 0} orientation 0 scale 1.000000
Why is that? Why isnt the image passed to ViewController2?

Answer 1

It seems to me that this could be a lot simpler. If you're using a Storyboard with a segue, you can easily accomplish this in prepare(for segue: UIStoryboardSegue, sender: Any?). Here's a sample storyboard:
In this case, ViewController has a segue on the Edit Image button to the EditImageViewController.
When you push that button, you get your prepare(for segue: call. Here's a sample ViewController:
class ViewController: UIViewController {
var imagePath = Bundle.main.path(forResource: "icon8", ofType: "png")
var anEditableImage:UIImage?
override func viewDidLoad() {
super.viewDidLoad()
if let imagePath = imagePath {
anEditableImage = UIImage(contentsOfFile: imagePath)
}
}
// MARK: - Navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let destination = segue.destination as? EditImageViewController {
destination.imageForEdit = anEditableImage
}
}
}
And here's the EditImageViewController:
class EditImageViewController: UIViewController {
var imageForEdit:UIImage?
override func viewDidLoad() {
super.viewDidLoad()
print(imageForEdit ?? "Image was nil")
}
}
Using prepare(for segue: UIStoryboardSegue, sender: Any?) is the preferred way for a Storyboard-based app to pass data between View Controllers. It's very simple and it works.
Sample project is here if you want to see the working code:
https://www.dropbox.com/s/eog01bmha67c5mv/PushImage.zip?dl=0

Answer 2

var imageForEdit: UIImage? {
didSet {
editingImage.image = imageForEdit
}
}

Answer 3

Replace var imageForEdit = UIImage() with var imageForEdit : UIImage?
i test code my self , make sure that imageView have image
#IBOutlet weak var imageView: UIImageView! {
didSet {
imageView.contentMode = .scaleAspectFill
imageView.clipsToBounds = true
}
}

Answer 4

You can create an public variable so you can pase data from one viewcontroller to another view controller.
class variables
{
static var image = UIImage()
}
the 2 controller:
#IBOutlet weak var anotherviewcontroller: UIImageView!
anotherviewcontroller.image = variables.image