Question

我在问是否可以使用gestureRecognizer设置UIImageView的图像，或者是否需要在UIImageView的顶部覆盖按钮。

我有一个UIImageViews的插座集合，名为imageViews。其中有四个，它们的标签已经设置为1到4.在我的viewDidLoad中，要将手势识别器添加到集合中的每个图像视图中，我使用过：

override func viewDidLoad() {
    super.viewDidLoad()

    for i in (0..<imageViews.count) {

        let imageViewTapped = UITapGestureRecognizer(target: self, action: #selector(selectImage(tap:)))
        imageViewTapped.numberOfTapsRequired = 1
        imageViews[i].addGestureRecognizer(imageViewTapped)

    }

}

接下来，我将gestureRecognizer创建为viewController类中的一个函数。这是创建图像选择器控制器的位置，以及识别被轻击的图像视图的位置：

func selectImage(tap: UITapGestureRecognizer) {

    var imagePicker = UIImagePickerController()
    imagePicker.delegate = self
    imagePicker.sourceType = .photoLibrary
    imagePicker.allowsEditing = false
    imagePicker.mediaTypes = UIImagePickerController.availableMediaTypes(for: .photoLibrary)!
    self.present(imagePicker, animated: true, completion: nil)

    guard let viewTappedTag = tap.view?.tag else {return}
    self.selectedImageView = imageViews[viewTappedTag - 1] 

}

selectedImageView是viewController类中的一个变量，其类型为UIImageView。我的想法是，这个变量可以保存被轻击的UIImageView，它由gestureRecognizer识别，如上所示。然后可以稍后将其传递给代理。

接下来，我创建了委托，didFinishPickingMediaWithInfo和didCancel，尽管我只是为了简洁而展示前者。两者都是在viewController类中创建的：

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

    var chosenImage = UIImage()
    chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
    self.selectedImageView.image = chosenImage

    dismiss(animated: true, completion: nil)

}

不幸的是，被点击的图像视图的图像未更新为从库中选择的图像。这样做的正确方法是什么？而且我觉得我的viewController充满了所有这些代码，这可以转移到一个单独的类吗？这样做我错了，而应该只是覆盖一个按钮？

修改

到目前为止我能想到的最好的是我的imagePickerController中的switch语句，其中imageViewOne，imageViewTwo等是每个UIImageView的出口：

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

    var chosenImage = UIImage()
    chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage

    switch self.viewTappedTag {
    case 1:
        imageViewOne.image = chosenImage
    case 2:
        imageViewTwo.image = chosenImage
    case 3:
        imageViewThree.image = chosenImage
    case 4:
        imageViewFour.image = chosenImage
    default:
        imageViewOne.image = chosenImage

    }

    dismiss(animated: true, completion: nil)

}

其中viewTappedTag是一个viewController类变量，其值由被轻击并在gestureRecognizer中设置的视图的标记定义。任何人都可以改进吗？

Answer 1

按以下方式更新代码

在类中声明一个变量，如下所示

var selectedImageViewIndex = 0 //by default selected image view is 0th image view


func selectImage(tap: UITapGestureRecognizer) {

    var imagePicker = UIImagePickerController()
    imagePicker.delegate = self
    imagePicker.sourceType = .photoLibrary
    imagePicker.allowsEditing = false
    imagePicker.mediaTypes = UIImagePickerController.availableMediaTypes(for: .photoLibrary)!
    self.present(imagePicker, animated: true, completion: nil)

    guard let viewTappedTag = tap.view?.tag else {return}

    self.selectedImageView = imageViews[viewTappedTag - 1] 

    //Add the following line
    self.selectedImageViewIndex = viewTappedTag - 1

}



func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

    var chosenImage = UIImage()
    chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
    self.selectedImageView.image = chosenImage

    //Add the following line
    self.imageView[self.selectedImageViewIndex].image = chosenImage
    dismiss(animated: true, completion: nil)

}

虽然我建议不要使用viewTappedTag - 1，而是从映射对象中获取index和tapped image标签的值。

Answer 2

最后我使用switch语句来实现我的目标：

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

var chosenImage = UIImage()
chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage

switch self.viewTappedTag {
case 1:
    imageViewOne.image = chosenImage
case 2:
    imageViewTwo.image = chosenImage
case 3:
    imageViewThree.image = chosenImage
case 4:
    imageViewFour.image = chosenImage
default:
    imageViewOne.image = chosenImage

}

dismiss(animated: true, completion: nil)

}

使用gestureRecognizer设置UIImageView的图像

2 个答案: