如何在Swift中使用XIB文件初始化/实例化自定义UIView类

我有一个称为MyClass的子类UIView，我想用一个XIB文件初始化。我不确定如何使用名为xib的文件初始化此类View.xib

class MyClass: UIView {

    // what should I do here? 
    //init(coder aDecoder: NSCoder) {} ?? 
}

我测试了这段代码，它很好用：

class MyClass: UIView {        
    class func instanceFromNib() -> UIView {
        return UINib(nibName: "nib file name", bundle: nil).instantiateWithOwner(nil, options: nil)[0] as UIView
    }    
}

初始化视图并按如下方式使用它：

var view = MyClass.instanceFromNib()
self.view.addSubview(view)

要么

var view = MyClass.instanceFromNib
self.view.addSubview(view())

更新Swift> = 3.x和Swift> = 4.x

class func instanceFromNib() -> UIView {
    return UINib(nibName: "nib file name", bundle: nil).instantiate(withOwner: nil, options: nil)[0] as! UIView
}

尽管Sam的解决方案没有考虑不同的捆绑软件（NSBundle：forClass可以解决），但它的解决方案已经非常出色，并且需要手动加载，也就是键入代码。

如果要全面支持Xib Outlet，不同的Bundle（在框架中使用！），并在Storyboard中获得不错的预览，请尝试以下操作：

// NibLoadingView.swift
import UIKit

/* Usage: 
- Subclass your UIView from NibLoadView to automatically load an Xib with the same name as your class
- Set the class name to File's Owner in the Xib file
*/

@IBDesignable
class NibLoadingView: UIView {

    @IBOutlet weak var view: UIView!

    override init(frame: CGRect) {
        super.init(frame: frame)
        nibSetup()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        nibSetup()
    }

    private func nibSetup() {
        backgroundColor = .clearColor()

        view = loadViewFromNib()
        view.frame = bounds
        view.autoresizingMask = [.FlexibleWidth, .FlexibleHeight]
        view.translatesAutoresizingMaskIntoConstraints = true

        addSubview(view)
    }

    private func loadViewFromNib() -> UIView {
        let bundle = NSBundle(forClass: self.dynamicType)
        let nib = UINib(nibName: String(self.dynamicType), bundle: bundle)
        let nibView = nib.instantiateWithOwner(self, options: nil).first as! UIView

        return nibView
    }

}

照常使用您的xib，即将Outlets连接到File Owner，并将File Owner类设置为您自己的类。

用法：从NibLoadingView和类名设置只要继承自己的视图类文件的所有者在XIB文件

不再需要其他代码。

贷项到期的贷项：与GH上的DenHeadless进行了细微的更改，从而进行了分叉。我的要旨：https : //gist.github.com/winkelsdorf/16c481f274134718946328b6e2c9a4d8

从Swift 2.0开始，您可以添加协议扩展。我认为这是一种更好的方法，因为返回类型Self不是UIView，所以调用者不需要转换为视图类。

import UIKit

protocol UIViewLoading {}
extension UIView : UIViewLoading {}

extension UIViewLoading where Self : UIView {

  // note that this method returns an instance of type `Self`, rather than UIView
  static func loadFromNib() -> Self {
    let nibName = "\(self)".characters.split{$0 == "."}.map(String.init).last!
    let nib = UINib(nibName: nibName, bundle: nil)
    return nib.instantiateWithOwner(self, options: nil).first as! Self
  }

}

这就是Frederik在Swift 3.0上的答案

/*
 Usage:
 - make your CustomeView class and inherit from this one
 - in your Xib file make the file owner is your CustomeView class
 - *Important* the root view in your Xib file must be of type UIView
 - link all outlets to the file owner
 */
@IBDesignable
class NibLoadingView: UIView {

    @IBOutlet weak var view: UIView!

    override init(frame: CGRect) {
        super.init(frame: frame)
        nibSetup()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        nibSetup()
    }

    private func nibSetup() {
        backgroundColor = .clear

        view = loadViewFromNib()
        view.frame = bounds
        view.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        view.translatesAutoresizingMaskIntoConstraints = true

        addSubview(view)
    }

    private func loadViewFromNib() -> UIView {
        let bundle = Bundle(for: type(of: self))
        let nib = UINib(nibName: String(describing: type(of: self)), bundle: bundle)
        let nibView = nib.instantiate(withOwner: self, options: nil).first as! UIView

        return nibView
    }
}

从xib加载视图的通用方法：

例：

let myView = Bundle.loadView(fromNib: "MyView", withType: MyView.self)

实现方式：

extension Bundle {

    static func loadView<T>(fromNib name: String, withType type: T.Type) -> T {
        if let view = Bundle.main.loadNibNamed(name, owner: nil, options: nil)?.first as? T {
            return view
        }

        fatalError("Could not load view with type " + String(describing: type))
    }
}

Swift 3回答：就我而言，我想在我的自定义类中有一个可以修改的插座：

class MyClassView: UIView {
    @IBOutlet weak var myLabel: UILabel!

    class func createMyClassView() -> MyClass {
        let myClassNib = UINib(nibName: "MyClass", bundle: nil)
        return myClassNib.instantiate(withOwner: nil, options: nil)[0] as! MyClassView
    }
}

在.xib中时，请确保“自定义类”字段为MyClassView。不要打扰文件的所有者。

另外，请确保将MyClassView中的插座连接到标签：

实例化它：

let myClassView = MyClassView.createMyClassView()
myClassView.myLabel.text = "Hello World!"

斯威夫特4

在这种情况下，我必须将数据传递到该自定义视图中，因此我创建了静态函数来实例化该视图。

1. 创建UIView扩展

   extension UIView {
       class func initFromNib<T: UIView>() -> T {
           return Bundle.main.loadNibNamed(String(describing: self), owner: nil, options: nil)?[0] as! T
       }
   }

2. 创建MyCustomView

   class MyCustomView: UIView {
   
       @IBOutlet weak var messageLabel: UILabel!
   
       static func instantiate(message: String) -> MyCustomView {
           let view: MyCustomView = initFromNib()
           view.messageLabel.text = message
           return view
       }
   }

3. 在.xib文件中将自定义类设置为MyCustomView。照常连接插座。

4. 实例化视图

   let view = MyCustomView.instantiate(message: "Hello World.")

override func draw(_ rect: CGRect) 
{
    AlertView.layer.cornerRadius = 4
    AlertView.clipsToBounds = true

    btnOk.layer.cornerRadius = 4
    btnOk.clipsToBounds = true   
}

class func instanceFromNib() -> LAAlertView {
    return UINib(nibName: "LAAlertView", bundle: nil).instantiate(withOwner: nil, options: nil)[0] as! LAAlertView
}

@IBAction func okBtnDidClicked(_ sender: Any) {

    removeAlertViewFromWindow()

    UIView.animate(withDuration: 0.4, delay: 0.0, options: .allowAnimatedContent, animations: {() -> Void in
        self.AlertView.transform = CGAffineTransform(scaleX: 0.1, y: 0.1)

    }, completion: {(finished: Bool) -> Void in
        self.AlertView.transform = CGAffineTransform.identity
        self.AlertView.transform = CGAffineTransform(scaleX: 0.0, y: 0.0)
        self.AlertView.isHidden = true
        self.AlertView.alpha = 0.0

        self.alpha = 0.5
    })
}


func removeAlertViewFromWindow()
{
    for subview  in (appDel.window?.subviews)! {
        if subview.tag == 500500{
            subview.removeFromSuperview()
        }
    }
}


public func openAlertView(title:String , string : String ){

    lblTital.text  = title
    txtView.text  = string

    self.frame = CGRect(x: 0, y: 0, width: screenWidth, height: screenHeight)
    appDel.window!.addSubview(self)


    AlertView.alpha = 1.0
    AlertView.isHidden = false

    UIView.animate(withDuration: 0.2, animations: {() -> Void in
        self.alpha = 1.0
    })
    AlertView.transform = CGAffineTransform(scaleX: 0.0, y: 0.0)

    UIView.animate(withDuration: 0.3, delay: 0.2, options: .allowAnimatedContent, animations: {() -> Void in
        self.AlertView.transform = CGAffineTransform(scaleX: 1.1, y: 1.1)

    }, completion: {(finished: Bool) -> Void in
        UIView.animate(withDuration: 0.2, animations: {() -> Void in
            self.AlertView.transform = CGAffineTransform(scaleX: 1.0, y: 1.0)

        })
    })


}