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将图像从ViewController传递到ViewController

xcode swift iphone ios

four-eyes · 技术社区 · 6 年前

我试图传递一个图像 ViewController1 到另一个 ViewController2 当一个按钮被点击时。我正在使用 segues 在我的故事板里。

视图控制器1

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) 结果

一些(uiImageView:0x7fc34df0e630;frame=(8 29;303 443);clipsToBounds=yes;opaque=no;autoresize=rm+bm;userInteractionEnabled=no;layer=calayer:0x60000023e520)

和 print(imageView.image!) 在里面

尺寸3000,2002方向0比例1.000000

视图控制器2

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) 结果

尺寸0,0方向0比例1.000000

为什么?为什么不把图像传递给 视图控制器2 ?

4 回复 | 直到 6 年前

David S. 6 年前

在我看来,这可能要简单得多。如果你用一个故事板和一个塞格,你可以很容易地完成这一点在 prepare(for segue: UIStoryboardSegue, sender: Any?) . 下面是一个故事板示例:

在这种情况下,ViewController在 Edit Image 按钮到 EditImageViewController .

当你按下那个按钮,你就会 prepare(for segue: 呼叫。以下是一个示例视图控制器:

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
        }
     }
}

这是 编辑图像查看控制器 :

class EditImageViewController: UIViewController {

    var imageForEdit:UIImage?

    override func viewDidLoad() {
        super.viewDidLoad()

        print(imageForEdit ?? "Image was nil")
    }
}

使用 准备(对于segue:uiStoryboardsegue,sender:any?) 是基于情节提要的应用程序在视图控制器之间传递数据的首选方法。这很简单,而且很有效。

如果要查看工作代码,请在此处显示示例项目:

https://www.dropbox.com/s/eog01bmha67c5mv/PushImage.zip?dl=0

Alexey Kudlay 6 年前

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

Abdelahad Darwish 6 年前

更换 var imageForEdit = UIImage() 具有 var imageForEdit : UIImage?

我自己测试代码,确保 imageView 有图像

 @IBOutlet weak var imageView: UIImageView! {
        didSet {
            imageView.contentMode = .scaleAspectFill
            imageView.clipsToBounds = true
        }
    }

Frederik L. Frandsen 6 年前

您可以创建一个公共变量,以便将数据从一个视图控制器传递到另一个视图控制器。

class variables
{
    static var image = UIImage()
}

2号控制器:

@IBOutlet weak var anotherviewcontroller: UIImageView!

anotherviewcontroller.image = variables.image