ios - String is not identical to NSObject 错误，同时在 Swift 中应用约束(视觉约束)

Question

import UIKit
import Foundation
class DetailView: UIViewController{
    var fullImage:UIImageView?
    var nameLabel:UILabel?
    var detailLabel:UILabel?

    override  func viewDidLoad() {
        super.viewDidLoad()
        fullImage = UIImageView()
        nameLabel = UILabel()
        detailLabel = UILabel()
        self.view.addSubview(fullImage!)
        self.view.addSubview(nameLabel!)
        self.view.addSubview(detailLabel!)
    }

    func applyContraints(){
        self.view.addSubview(fullImage!)

     fullImage?.setTranslatesAutoresizingMaskIntoConstraints(false)
     nameLabel?.setTranslatesAutoresizingMaskIntoConstraints(false)
     detailLabel?.setTranslatesAutoresizingMaskIntoConstraints(false)

        var viewsDict:[String:AnyObject!] = ["imageView": fullImage!, "nameLabel": nameLabel!, "detailLabel": detailLabel!]

        var constraints:NSArray

        constraints = NSLayoutConstraint.constraintsWithVisualFormat("H:|-10-[imageView]-10-|",
            options: 0,
            metrics: nil,
            views: viewsDict)
        self.view.addConstraints(constraints)



    }
}

Answer 1

constraintsWithVisualFormat 的views 参数需要一个[NSObject: AnyObject] 类型的字典。

在创建 viewsDict 时，尝试将其声明为 [NSObject: AnyObject]:

var viewsDict: [NSObject: AnyObject] = ["imageView": fullImage!, "nameLabel": nameLabel!, "detailLabel": detailLabel!]

您还必须将 options 参数值从 0 更改为 nil

此外，如果您想摆脱可选值，您可以尝试以下方法:

var fullImage = UIImageView()
var nameLabel = UILabel()
var detailLabel = UILabel()

代替:

var fullImage: UIImageView?
var nameLabel: UILabel?
var detailLabel: UILabel?

然后，对于 viewsDict 声明，您可以删除 !:

var viewsDict: [NSObject: AnyObject] = ["imageView": fullImage, "nameLabel": nameLabel, "detailLabel": detailLabel]