首页 > 解决方案 > Swift ImagePicker 在自动布局约束上抛出 SIGNAL SIGABRT

问题描述

我正在 Swift5 中构建一个项目,我需要用户上传照片。我已经达到了用户可以打开 ImagePicker 并选择照片的程度,但是每当他们选择图像并返回原始 VC 时,我都会收到 SIGNAL SIGABRT 错误(在帖子底部):

这是我以编程方式添加约束的地方:

func setupLayout(){
    imgView.topAnchor.constraint(equalTo: view.topAnchor, constant: 150).isActive = true
    imgView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    imgView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
    imgView.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
    imgView.heightAnchor.constraint(equalToConstant: 125).isActive = true

    topLabel.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    topLabel.topAnchor.constraint(equalTo: imgView.bottomAnchor, constant: 60).isActive = true
    topLabel.widthAnchor.constraint(equalTo: view.widthAnchor, constant: -50).isActive = true
    topLabel.heightAnchor.constraint(equalToConstant: 50).isActive = true
    topLabel.adjustsFontSizeToFitWidth = true

    inputBox.topAnchor.constraint(equalTo: topLabel.bottomAnchor, constant: 30).isActive = true
    inputBox.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    inputBox.heightAnchor.constraint(equalToConstant: 50).isActive = true
    inputBox.widthAnchor.constraint(equalToConstant: 250).isActive = true

    btn.topAnchor.constraint(equalTo: inputBox.bottomAnchor, constant: 40).isActive = true
    btn.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true

    let navBarImageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 10, height: 10))
    navBarImageView.contentMode = .scaleAspectFit
    let navBarImage = UIImage(named: "bzaLogo")
    navBarImageView.image = navBarImage
    self.navigationController?.navigationItem.titleView = navBarImageView
}

我在 imageView 上设置图像的位置:

func didSelect(image: UIImage?) {
    self.imgView.image = image
    self.global.uploadFile(imageView: self.uploadIcon.imageView!)
}

在我添加子视图的地方:

override func viewDidLoad() {
    super.viewDidLoad()
    currentState = 0
    imgView.translatesAutoresizingMaskIntoConstraints = false
    topLabel.translatesAutoresizingMaskIntoConstraints = false
    inputBox.translatesAutoresizingMaskIntoConstraints = false
    btn.translatesAutoresizingMaskIntoConstraints = false
    view.addSubview(imgView)
    view.addSubview(topLabel)
    view.addSubview(inputBox)
    view.addSubview(btn)

    inputBox.addTarget(self, action: #selector(inputBoxClicked(textField:)), for: .touchDown)
    imagePicker = ImagePicker(presentationController: self, delegate: self)
    viewModel.state = currentState
    inputBox.delegate = self

    setupLayout()
}

这是抛出的错误:

2019-06-12 13:22:16.635903-0600 bZa[39792:1836482] *** 由于未捕获的异常“NSGenericException”而终止应用程序,原因:“无法使用锚激活约束,因为它们没有共同的祖先。约束或其锚点是否引用不同视图层次结构中的项目?这是非法的。

标签: swiftxcodeuiimageviewuiimagepickercontroller

解决方案


目前的问题是您在没有评论祖先的视图之间添加约束,因此请验证您添加

view.addSubview(imgView)  
view.addSubview(topLabel) 
view.addSubview(inputBox)
view.addSubview(btn)

也不要忘记

imgView.translatesAutoresizingMaskIntoConstraints = false 
topLabel.translatesAutoresizingMaskIntoConstraints = false
inputBox.translatesAutoresizingMaskIntoConstraints = false
btn.translatesAutoresizingMaskIntoConstraints = false

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