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。
这是一个很好的问题(+1)，答案几乎是有帮助的;)抱歉，伙计们，虽然Gonso和AVeryDev都给出了很好的提示，但我花了很长时间才读完这篇文章。希望这个答案能帮助到其他人。
MyVC是持有这些东西的视图控制器。
MySubview是我们想从xib中加载的视图
In MyVC.xib, create a view of type MySubView that is the right size & shape & positioned where you want it.
In MyVC.h, have
IBOutlet MySubview *mySubView
// ...
@property (nonatomic, retain) MySubview *mySubview;
In MyVC.m, @synthesize mySubView; and don't forget to release it in dealloc.
In MySubview.h, have an outlet/property for UIView *view (may be unnecessary, but worked for me.) Synthesize & release it in .m
In MySubview.xib
set file owner type to MySubview, and link the view property to your view.
Lay out all the bits & connect to the IBOutlet's as desired
Back in MyVC.m, have
NSArray *xibviews = [[NSBundle mainBundle] loadNibNamed: @"MySubview" owner: mySubview options: NULL];
MySubview *msView = [xibviews objectAtIndex: 0];
msView.frame = mySubview.frame;
UIView *oldView = mySubview;
// Too simple: [self.view insertSubview: msView aboveSubview: mySubview];
[[mySubview superview] insertSubview: msView aboveSubview: mySubview]; // allows nesting
self.mySubview = msView;
[oldCBView removeFromSuperview];
对我来说棘手的一点是:其他答案中的提示从xib加载了我的视图，但没有替换MyVC中的视图(呸!)——我必须自己交换。
同样，为了访问mySubview的方法，.xib文件中的view属性必须设置为mySubview。否则，它会返回一个普通的UIView。
如果有一种方法来加载mySubview直接从它自己的xib，那将摇滚，但这让我在我需要的地方。
这是一个很好的问题(+1)，答案几乎是有帮助的;)抱歉，伙计们，虽然Gonso和AVeryDev都给出了很好的提示，但我花了很长时间才读完这篇文章。希望这个答案能帮助到其他人。
MyVC是持有这些东西的视图控制器。
MySubview是我们想从xib中加载的视图
In MyVC.xib, create a view of type MySubView that is the right size & shape & positioned where you want it.
In MyVC.h, have
IBOutlet MySubview *mySubView
// ...
@property (nonatomic, retain) MySubview *mySubview;
In MyVC.m, @synthesize mySubView; and don't forget to release it in dealloc.
In MySubview.h, have an outlet/property for UIView *view (may be unnecessary, but worked for me.) Synthesize & release it in .m
In MySubview.xib
set file owner type to MySubview, and link the view property to your view.
Lay out all the bits & connect to the IBOutlet's as desired
Back in MyVC.m, have
NSArray *xibviews = [[NSBundle mainBundle] loadNibNamed: @"MySubview" owner: mySubview options: NULL];
MySubview *msView = [xibviews objectAtIndex: 0];
msView.frame = mySubview.frame;
UIView *oldView = mySubview;
// Too simple: [self.view insertSubview: msView aboveSubview: mySubview];
[[mySubview superview] insertSubview: msView aboveSubview: mySubview]; // allows nesting
self.mySubview = msView;
[oldCBView removeFromSuperview];
对我来说棘手的一点是:其他答案中的提示从xib加载了我的视图，但没有替换MyVC中的视图(呸!)——我必须自己交换。
同样，为了访问mySubview的方法，.xib文件中的view属性必须设置为mySubview。否则，它会返回一个普通的UIView。
如果有一种方法来加载mySubview直接从它自己的xib，那将摇滚，但这让我在我需要的地方。
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。
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
花了好几个小时后，我想出了以下解决办法。
按照以下步骤创建自定义UIView。
1)创建类myCustomView继承自UIView。
2)创建名称为myCustomView的.xib。
3)在你的.xib文件中改变UIView的类，在那里分配myCustomView类。
4)创建iboutlet
5)在myCustomView * customView中加载.xib。
使用下面的示例代码。
myCustomView * myView = [[[NSBundle mainBundle] loadNibNamed:@"myCustomView" owner:self options:nil] objectAtIndex:0];
[myView.description setText:@"description"];
注:对于那些仍然面临问题的人可以评论，我将提供他们的链接
示例项目的myCustomView
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
}
