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

我最终为这个添加了一个类别到UIView:

 #import "UIViewNibLoading.h"

 @implementation UIView (UIViewNibLoading)

 + (id) loadNibNamed:(NSString *) nibName {
    return [UIView loadNibNamed:nibName fromBundle:[NSBundle mainBundle] retainingObjectWithTag:1];
 }

 + (id) loadNibNamed:(NSString *) nibName fromBundle:(NSBundle *) bundle retainingObjectWithTag:(NSUInteger) tag {
    NSArray * nib = [bundle loadNibNamed:nibName owner:nil options:nil];
    if(!nib) return nil;
    UIView * target = nil;
    for(UIView * view in nib) {
        if(view.tag == tag) {
            target = [view retain];
            break;
        }
    }
    if(target && [target respondsToSelector:@selector(viewDidLoad)]) {
        [target performSelector:@selector(viewDidLoad)];
    }
    return [target autorelease];
 }

 @end

这里的解释:在ios和mac中viewcontroller是更少的视图加载

对于那些需要管理多个自定义视图实例的人，也就是Outlet Collection，我合并并定制了@Gonso， @AVeryDev和@Olie的答案:

Create a custom MyView : UIView and set it as "Custom Class" of the root UIView in the desired XIB; Create all outlets you need in MyView (do it now because after point 3 the IB will propose you to connect outlets to the UIViewController and not to the custom view as we want); Set your UIViewController as "File's Owner" of the custom view XIB; In the UIViewController add a new UIViews for each instance of MyView you want, and connect them to UIViewController creating an Outlet Collection: these views will act as "wrapper" views for the custom view instances; Finally, in the viewDidLoad of your UIViewController add the following lines:

NSArray *bundleObjects; MyView *currView; NSMutableArray *myViews = [NSMutableArray arrayWithCapacity:myWrapperViews.count]; for (UIView *currWrapperView in myWrapperViews) { bundleObjects = [[NSBundle mainBundle] loadNibNamed:@"MyView" owner:self options:nil]; for (id object in bundleObjects) { if ([object isKindOfClass:[MyView class]]){ currView = (MyView *)object; break; } } [currView.myLabel setText:@"myText"]; [currView.myButton setTitle:@"myTitle" forState:UIControlStateNormal]; //... [currWrapperView addSubview:currView]; [myViews addObject:currView]; } //self.myViews = myViews; if need to access them later..

下面是一种在Swift中实现的方法(目前正在XCode 7 beta 5中编写Swift 2.0)。

从你在接口构建器中设置为“自定义类”的UIView子类中创建一个像这样的方法(我的子类叫做RecordingFooterView):

class func loadFromNib() -> RecordingFooterView? {
    let nib = UINib(nibName: "RecordingFooterView", bundle: nil)
    let nibObjects = nib.instantiateWithOwner(nil, options: nil)
    if nibObjects.count > 0 {
        let topObject = nibObjects[0]
        return topObject as? RecordingFooterView
    }
    return nil
}

然后你可以像这样调用它:

let recordingFooterView = recordingFooterView . loadfromnib ()

我也想做一些类似的事情，这是我发现的: (SDK 3.1.3)

我有一个视图控制器a(本身由一个导航控制器拥有)，它在一个按钮按下加载VC B:

在AViewController.m

BViewController *bController = [[BViewController alloc] initWithNibName:@"Bnib" bundle:nil];
[self.navigationController pushViewController:bController animated:YES];
[bController release];

现在VC B有它的接口从Bnib，但当一个按钮被按下，我想去一个“编辑模式”有一个独立的UI从不同的nib，但我不想要一个新的VC的编辑模式，我想新的nib与我现有的B VC相关联。

在BViewController中。M(按按钮方式)

NSArray *nibObjects = [[NSBundle mainBundle] loadNibNamed:@"EditMode" owner:self options:nil];
UIView *theEditView = [nibObjects objectAtIndex:0];
self.editView = theEditView;
[self.view addSubview:theEditView];

然后按下另一个按钮(退出编辑模式):

[editView removeFromSuperview];

我又变回了原来的Bnib

这很好，但请注意我的EditMode。nib中只有一个顶级obj，一个UIView obj。 不管这个nib中的文件所有者是设置为BViewController还是默认的NSObject，但要确保文件所有者中的视图出口没有设置为任何东西。 如果是，那么我得到一个exc_bad_access崩溃，xcode继续加载6677个堆栈帧 显示一个内部UIView方法被反复调用…看起来像一个无限循环。 (视图出口是设置在我原来的Bnib然而)

希望这能有所帮助。