我试着做一些复杂的事情,但应该是可能的。所以这里有一个对你们所有专家的挑战(这个论坛是由你们很多人组成的:))。

我正在创建一个问卷“组件”,我想加载在一个navigationcontroller(我的QuestionManagerViewController)。“组件”是一个“空的”UIViewController,它可以根据需要回答的问题加载不同的视图。

我的做法是:

Create Question1View object as a UIView subclass, defining some IBOutlets. Create (using Interface Builder) the Question1View.xib (HERE IS WHERE MY PROBLEM PROBABLY IS). I set both the UIViewController and the UIView to be of class Question1View. I link the outlets with the view's component (using IB). I override the initWithNib of my QuestionManagerViewController to look like this: - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { if (self = [super initWithNibName:@"Question1View" bundle:nibBundleOrNil]) { // Custom initialization } return self; }

当我运行代码时,我得到这个错误:

2009-05-14 15:05:37.152 iMobiDines[17148:20b] ***由于未捕获异常'NSInternalInconsistencyException'而终止应用程序,原因:'-[UIViewController _loadViewFromNibNamed:bundle:] loaded the "Question1View" nib but the view outlet was not set.'

我确信有一种方法可以使用nib文件加载视图,而不需要创建一个viewController类。


当前回答

前面的答案没有考虑iPhone SDK 2.0到2.1之间发生的NIB (XIB)结构的变化。用户内容现在从索引0开始,而不是1。

你可以使用2.1宏,它适用于所有2.1及以上版本(在IPHONE前面加两个下划线):

 // Cited from previous example
 NSArray* nibViews =  [[NSBundle mainBundle] loadNibNamed:@"QPickOneView" owner:self options:nil];
 int startIndex;
 #ifdef __IPHONE_2_1
 startIndex = 0;
 #else
 startIndex = 1;
 #endif
 QPickOneView* myView = [ nibViews objectAtIndex: startIndex];
 myView.question = question;

我们在大多数应用程序中都使用类似的技术。

巴尼

其他回答

我发现Aaron Hillegass(作者,讲师,可可忍者)的这篇博客非常有启发性。即使您不采用他修改后的方法通过指定的初始化器加载NIB文件,您也至少可以更好地理解正在进行的过程。我最近一直在用这个方法,而且非常成功!

Swift用户可设计选项:

Create a custom UIView subclass and a xib files, that we will name after our own class name: in our case MemeView. Inside the Meme View class remember to define it as designable with the @IBDesignable attribute before the class declaration Rember to set the File’s Owner in the xib with our custom UIView subclass in Indetity Inspector panel In the xib file now we can build our interface, make constraints, create outlets, actions etc. We need to implement few methods to our custom class to open the xib once initialized class XibbedView: UIView { weak var nibView: UIView! override convenience init(frame: CGRect) { let nibName = NSStringFromClass(self.dynamicType).componentsSeparatedByString(".").last! self.init(nibName: nibName) } required init?(coder aDecoder: NSCoder) { super.init(coder: aDecoder) let nibName = NSStringFromClass(self.dynamicType).componentsSeparatedByString(".").last! let nib = loadNib(nibName) nib.frame = bounds nib.translatesAutoresizingMaskIntoConstraints = false addSubview(nib) nibView = nib setUpConstraints() } init(nibName: String) { super.init(frame: CGRectZero) let nibName = NSStringFromClass(self.dynamicType).componentsSeparatedByString(".").last! let nib = loadNib(nibName) nib.frame = bounds nib.translatesAutoresizingMaskIntoConstraints = false addSubview(nib) nibView = nib setUpConstraints() } func setUpConstraints() { ["V","H"].forEach { (quote) -> () in let format = String(format:"\(quote):|[nibView]|") addConstraints(NSLayoutConstraint.constraintsWithVisualFormat(format, options: [], metrics: nil, views: ["nibView" : nibView])) } } func loadNib(name: String) -> UIView { let bundle = NSBundle(forClass: self.dynamicType) let nib = UINib(nibName: name, bundle: bundle) let view = nib.instantiateWithOwner(self, options: nil)[0] as! UIView return view } } In our custom class we can also define some inspecatable properties to have full control over them from interface builder @IBDesignable class MemeView: XibbedView { @IBInspectable var memeImage: UIImage = UIImage() { didSet { imageView.image = memeImage } } @IBInspectable var textColor: UIColor = UIColor.whiteColor() { didSet { label.textColor = textColor } } @IBInspectable var text: String = "" { didSet { label.text = text } } @IBInspectable var roundedCorners: Bool = false { didSet { if roundedCorners { layer.cornerRadius = 20.0 clipsToBounds = true } else { layer.cornerRadius = 0.0 clipsToBounds = false } } } @IBOutlet weak var label: UILabel! @IBOutlet weak var imageView: UIImageView!

}

一些例子:

如果我们需要在一个故事板或另一个xib中显示视图时添加更多信息,为此我们可以实现prepareForInterfaceBuilder(),此方法仅在接口生成器中打开文件时执行。 如果你做了我写的所有事情,但没有任何工作,这是一种通过在实现中添加断点来调试单个视图的方法。 这是视图层次结构。

希望这对您有所帮助,完整的示例可以在这里下载

在Swift 4中以编程方式从nib/xib加载视图:

// Load a view from a Nib given a placeholder view subclass
//      Placeholder is an instance of the view to load.  Placeholder is discarded.
//      If no name is provided, the Nib name is the same as the subclass type name
//
public func loadViewFromNib<T>(placeholder placeholderView: T, name givenNibName: String? = nil) -> T {

    let nib = loadNib(givenNibName, placeholder: placeholderView)
    return instantiateView(fromNib: nib, placeholder: placeholderView)
}

// Step 1: Returns a Nib
//
public func loadNib<T>(_ givenNibName: String? = nil, placeholder placeholderView: T) -> UINib {
    //1. Load and unarchive nib file
    let nibName = givenNibName ?? String(describing: type(of: placeholderView))

    let nib = UINib(nibName: nibName, bundle: Bundle.main)
    return nib
}

// Step 2: Instantiate a view given a nib
//
public func instantiateView<T>(fromNib nib: UINib, placeholder placeholderView: T) -> T {
    //1. Get top level objects
    let topLevelObjects = nib.instantiate(withOwner: placeholderView, options: nil)

    //2. Have at least one top level object
    guard let firstObject = topLevelObjects.first else {
        fatalError("\(#function): no top level objects in nib")
    }

    //3. Return instantiated view, placeholderView is not used
    let instantiatedView = firstObject as! T
    return instantiatedView
}

前面的答案没有考虑iPhone SDK 2.0到2.1之间发生的NIB (XIB)结构的变化。用户内容现在从索引0开始,而不是1。

你可以使用2.1宏,它适用于所有2.1及以上版本(在IPHONE前面加两个下划线):

 // Cited from previous example
 NSArray* nibViews =  [[NSBundle mainBundle] loadNibNamed:@"QPickOneView" owner:self options:nil];
 int startIndex;
 #ifdef __IPHONE_2_1
 startIndex = 0;
 #else
 startIndex = 1;
 #endif
 QPickOneView* myView = [ nibViews objectAtIndex: startIndex];
 myView.question = question;

我们在大多数应用程序中都使用类似的技术。

巴尼

最短的版本:

RSFavoritePlaceholderView *favoritePlaceholderView = [[[NSBundle mainBundle] loadNibNamed:@"RSFavoritePlaceholderView" owner:self options:nil] firstObject];