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

我有理由做同样的事情(从XIB文件编程加载一个视图),但我需要完全从一个UIView的子类的子类的上下文(即不涉及视图控制器的任何方式)。为了做到这一点,我创建了这个实用方法:

+ (id) initWithNibName:(NSString *)nibName withSelf:(id)myself {

    NSArray *bundle = [[NSBundle mainBundle] loadNibNamed:nibName
                                                    owner:myself options:nil];
    for (id object in bundle) {
        if ([object isKindOfClass:[myself class]]) {
            return object;
        }
    }  

    return nil;
} 

然后我从我的子类的initWithFrame方法调用它,如下所示:

- (id)initWithFrame:(CGRect)frame {

    self = [Utilities initWithNibName:@"XIB1" withSelf:self];
    if (self) {
        // Initialization code.
    }
    return self;
}

张贴的一般利益;如果有人发现没有这样做的问题,请告诉我。

其他回答

这是一件应该比较容易的事情。我最终扩展了UIViewController并添加了一个loadNib:inPlaceholder: selector。现在我可以说

self.mySubview = (MyView *)[self loadNib:@"MyView" inPlaceholder:mySubview];

下面是这个类别的代码(它和Gonso描述的一样):

@interface UIViewController (nibSubviews)

- (UIView *)viewFromNib:(NSString *)nibName;
- (UIView *)loadNib:(NSString *)nibName inPlaceholder:(UIView *)placeholder;

@end

@implementation UIViewController (nibSubviews)

- (UIView *)viewFromNib:(NSString *)nibName
{
  NSArray *xib = [[NSBundle mainBundle] loadNibNamed:nibName owner:self options:nil]; 
  for (id view in xib) { // have to iterate; index varies
    if ([view isKindOfClass:[UIView class]]) return view;
  }
  return nil;
}

- (UIView *)loadNib:(NSString *)nibName inPlaceholder:(UIView *)placeholder
{
  UIView *nibView = [self viewFromNib:nibName];
  [nibView setFrame:placeholder.frame];
  [self.view insertSubview:nibView aboveSubview:placeholder];
  [placeholder removeFromSuperview];
  return nibView;
}

@end

我做了一个我喜欢的分类:

UIView + NibInitializer.h

#import <UIKit/UIKit.h>

@interface UIView (NibInitializer)
- (instancetype)initWithNibNamed:(NSString *)nibNameOrNil;
@end

UIView + NibInitializer.m

#import "UIView+NibInitializer.h"

@implementation UIView (NibInitializer)

- (instancetype)initWithNibNamed:(NSString *)nibNameOrNil
{
    if (!nibNameOrNil) {
        nibNameOrNil = NSStringFromClass([self class]);
    }
    NSArray *viewsInNib = [[NSBundle mainBundle] loadNibNamed:nibNameOrNil
                                                        owner:self
                                                      options:nil];
    for (id view in viewsInNib) {
        if ([view isKindOfClass:[self class]]) {
            self = view;
            break;
        }
    }
    return self;
}

@end

然后,像这样调用:

MyCustomView *myCustomView = [[MyCustomView alloc] initWithNibNamed:nil];

如果你的nib不是你的类名,请使用一个nib名。

为了在你的子类中覆盖它以获得额外的行为,它可以看起来像这样:

- (instancetype)initWithNibNamed:(NSString *)nibNameOrNil
{
    self = [super initWithNibNamed:nibNameOrNil];
    if (self) {
        self.layer.cornerRadius = CGRectGetHeight(self.bounds) / 2.0;
    }
    return self;
}

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。

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..