ios 为 UIView 子类加载 Nib 的正确方法

Correct way to load a Nib for a UIView subclass

提问by Adam Waite

I am aware this question has been asked before but the answers are contradicting and I am confused, so please don't flame me.

我知道以前有人问过这个问题，但答案是矛盾的，我很困惑，所以请不要喷我。

I want to have a reusable UIViewsubclass throughout my app. I want to describe the interface using a nib file.

我想UIView在我的应用程序中拥有一个可重用的子类。我想用一个 nib 文件来描述界面。

Now let's say it's a loading indicator view with an activity indicator in it. I would like on some event to instantiate this view and animate in to a view controller's view. I could describe the view's interface no problem programmatically, creating the elements programmatically and setting their frame inside an init method etc.

现在假设它是一个加载指示器视图，其中包含一个活动指示器。我希望在某个事件中实例化此视图并将动画添加到视图控制器的视图中。我可以以编程方式描述视图的界面，以编程方式创建元素并在 init 方法中设置它们的框架等。

How can I do this using a nib though? Maintaining the size given in interface builder without having to set a frame.

我怎么能用笔尖做到这一点？保持界面构建器中给定的大小，而无需设置框架。

I've managed to do it like this, but I'm sure it is wrong (it's just a view with a picker in it):

我已经设法这样做了，但我确定这是错误的（它只是一个带有选择器的视图）：

 - (id)initWithDataSource:(NSDictionary *)dataSource {
        self = [super init];
        if (self){
            self = [[[NSBundle mainBundle] loadNibNamed:[NSString stringWithFormat:@"%@", [self class]] owner:self options:nil] objectAtIndex:0];
            self.pickerViewData = dataSource;
            [self configurePickerView];
        }
        return self;
    }

But I'm overwriting self, and when I instantiate it:

但是我正在覆盖自我，当我实例化它时：

FSASelectView *selectView = [[FSASelectView alloc] initWithDataSource:selectViewDictionary];
    selectView.delegate = self;

    selectView.frame = CGRectMake(0, self.view.bottom + 50, [FSASelectView width], [FSASelectView height]);

I have to manually set the frame rather than have it picked up from IB.

我必须手动设置框架，而不是从 IB 获取它。

EDIT: I want to create this custom view in a view controller, and have access to control the view's elements. I don't want a new view controller.

编辑：我想在视图控制器中创建这个自定义视图，并有权控制视图的元素。我不想要一个新的视图控制器。

Thanks

谢谢

EDIT: I Don't know if this is best practice, I'm sure it's not, but this is how I did it:

编辑：我不知道这是否是最佳实践，我确定不是，但我是这样做的：

FSASelectView *selectView = [[[NSBundle mainBundle] loadNibNamed:[NSString stringWithFormat:@"%@",[FSASelectView class]] owner:self options:nil] objectAtIndex:0];
    selectView.delegate = self;
    [selectView configurePickerViewWithData:ds];
    selectView.frame = CGRectMake(0, self.view.bottom + 50, selectView.width, selectView.height);
    selectView.alpha = 0.9;
    [self.view addSubview:selectView];
    [UIView animateWithDuration: 0.25 delay: 0 options:UIViewAnimationOptionAllowUserInteraction |UIViewAnimationOptionCurveEaseInOut animations:^{
                            selectView.frame = CGRectMake(0, self.view.bottom - selectView.height, selectView.width, selectView.height);
                            selectView.alpha = 1;
                        } completion:^(BOOL finished) {
                        }];

Correct practice still wanted

仍然需要正确的练习

Should this have been done using a view controller and init with nib name? Should I have set the nib in some UIView initialisation method in the code? Or is what I have done ok?

这是否应该使用视图控制器和带有 nib 名称的 init 来完成？我应该在代码中的某些 UIView 初始化方法中设置笔尖吗？或者我所做的一切正常吗？

回答by Premsuraj

MyViewClass *myViewObject = [[[NSBundle mainBundle] loadNibNamed:@"MyViewClassNib" owner:self options:nil] objectAtIndex:0]

I'm using this to initialise the reusable custom views I have.

我正在使用它来初始化我拥有的可重用自定义视图。

---

---

Note that you can use "firstObject"at the end there, it's a little cleaner. "firstObject" is a handy method for NSArray and NSMutableArray.

请注意，您可以在最后使用“firstObject”，它更简洁一些。“firstObject”是 NSArray 和 NSMutableArray 的一个方便的方法。

Here's a typical example, of loading a xib to use as a table header. In your file YourClass.m

这是一个典型的例子，加载一个 xib 用作表头。在您的文件 YourClass.m 中

- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
    return [[NSBundle mainBundle] loadNibNamed:@"TopArea" owner:self options:nil].firstObject;
}

Normally, in the TopArea.xib, you would click on File Owner and set the file owner to YourClass. Then actually in YourClass.hyou would have IBOutlet properties. In TopArea.xib, you can drag controls to those outlets.

通常，在 中TopArea.xib，您将单击 File Owner 并将文件所有者设置为 YourClass。然后实际上在 YourClass.h 中，您将拥有 IBOutlet 属性。在 中TopArea.xib，您可以将控件拖动到这些出口。

Don't forget that in TopArea.xib, you may have to click on the View itselfand drag that to some outlet, so you have control of it, if necessary. (A very worthwhile tip is that when you are doing this for table cell rows, you absolutely have to do that - you have to connect the view itself to the relevant property in your code.)

不要忘记在 中TopArea.xib，您可能必须单击视图本身并将其拖到某个出口，以便在必要时控制它。（一个非常有价值的提示是，当您对表格单元格行执行此操作时，您绝对必须这样做 - 您必须将视图本身连接到代码中的相关属性。）

回答by Ans

If you want to keep your CustomViewand its xibindependent of File's Owner, then follow these steps

如果你想保持你的CustomView和它的xib独立File's Owner，那么按照这些步骤

• Leave the File's Ownerfield empty.
• Click on actual view in xibfile of your CustomViewand set its Custom Classas CustomView(name of your custom view class)
• Add IBOutletin .hfile of your custom view.
• In .xibfile of your custom view, click on view and go in Connection Inspector. Here you will all your IBOutlets which you define in .hfile
• Connect them with their respective view.

• 将该File's Owner字段留空。
• 单击xib文件中的实际视图CustomView并将其设置Custom Class为CustomView（自定义视图类的名称）
• 添加IBOutlet在.h您的自定义视图的文件。
• 在.xib自定义视图的文件中，单击视图并进入Connection Inspector。在这里，您将在.h文件中定义所有 IBOutlets
• 将它们与各自的视图联系起来。

in .mfile of your CustomViewclass, override the initmethod as follow

在.m您的CustomView班级文件中，init按如下方式覆盖该方法

-(CustomView *) init{
    CustomView *result = nil;
    NSArray* elements = [[NSBundle mainBundle] loadNibNamed: NSStringFromClass([self class]) owner:self options: nil];
    for (id anObject in elements)
    {
        if ([anObject isKindOfClass:[self class]])
        {
            result = anObject;
            break;
        }
    }
    return result;
}

Now when you want to load your CustomView, use the following line of code [[CustomView alloc] init];

现在，当您要加载您的 时CustomView，请使用以下代码行 [[CustomView alloc] init];

回答by iphonic

Follow the following steps

请按照以下步骤操作

1. Create a class named MyView .h/.m of type UIView.
2. Create a xib of same name MyView.xib.
3. Now change the File Owner class to UIViewControllerfrom NSObjectin xib. See the image below

4. Connect the File Owner View to your View. See the image below

5. Change the class of your View to MyView. Same as 3.

6. Place controls create IBOutlets.

1. 创建一个名为 MyView .h/.m 的类，类型为UIView。
2. 创建一个同名的 xib MyView.xib。
3. 现在在 xib 中将File Owner 类更改为UIViewControllerfrom NSObject。见下图

4. 将文件所有者视图连接到您的视图。见下图

5. 将视图的类更改为MyView. 与 3 相同。

6. 放置控件创建IBOutlets。

Here is the code to load the View:

这是加载视图的代码：

UIViewController *controller=[[UIViewController alloc] initWithNibName:@"MyView" bundle:nil];
MyView* view=(MyView*)controller.view;
[self.view addSubview:myview];

Hope it helps.

希望能帮助到你。

Clarification:

澄清：

UIViewControlleris used to load your xib and the View which the UIViewControllerhas is actually MyViewwhich you have assigned in the MyView xib..

UIViewController用于加载您的 xib 和视图，该视图UIViewController实际上MyView是您在 MyView xib 中分配的。

DemoI have made a demo grab here

演示我在这里做了一个演示抓取

回答by Adam Waite

Answering my own question about 2 or something years later here but...

在这里回答我自己关于 2 年或几年后的问题，但是......

It uses a protocol extension so you can do it without any extra code for all classes.

它使用协议扩展，因此您无需为所有类添加任何额外代码即可完成此操作。

/*

Prerequisites
-------------
- In IB set the view's class to the type hook up any IBOutlets
- In IB ensure the file's owner is blank

*/

public protocol CreatedFromNib {
    static func createFromNib() -> Self?
    static func nibName() -> String?
}

extension UIView: CreatedFromNib { }

public extension CreatedFromNib where Self: UIView {

    public static func createFromNib() -> Self? {
        guard let nibName = nibName() else { return nil }
        guard let view = NSBundle.mainBundle().loadNibNamed(nibName, owner: nil, options: nil).last as? Self else { return nil }
        return view
    }

    public static func nibName() -> String? {
        guard let n = NSStringFromClass(Self.self).componentsSeparatedByString(".").last else { return nil }
        return n
    }
}

// Usage:
let myView = MyView().createFromNib()

回答by vkalit

In Swift:

在斯威夫特：

For example, name of your custom class is InfoView

例如，您的自定义类的名称是 InfoView

At first, you create files InfoView.xiband InfoView.swiftlike this:

首先，您创建文件InfoView.xib，InfoView.swift如下所示：

import Foundation
import UIKit

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

Then set File's Ownerto UIViewControllerlike this:

然后设置File's Owner成UIViewController这样：

Rename your Viewto InfoView:

将您的重命名View为InfoView：

Right-click to File's Ownerand connect your viewfield with your InfoView:

右键单击File's Owner并将您的view字段与您的InfoView：

Make sure that class name is InfoView:

确保类名是InfoView：

And after this you can add the action to button in your custom class without any problem:

在此之后，您可以毫无问题地将操作添加到自定义类中的按钮：

And usage of this custom class in your MainViewController:

并在您的 中使用此自定义类MainViewController：

func someMethod() {
    var v = InfoView.instanceFromNib()
    v.frame = self.view.bounds
    self.view.addSubview(v)
}

回答by Rakesh

Well you could either initialize the xib using a view controller and use viewController.view. or do it the way you did it. Only making a UIViewsubclass as the controller for UIViewis a bad idea.

好吧，您可以使用视图控制器初始化 xib 并使用 viewController.view。或者按照你的方式去做。只将UIView子类作为控制器UIView是一个坏主意。

If you don't have any outlets from your custom view then you can directly use a UIViewControllerclass to initialize it.

如果您的自定义视图中没有任何插座，那么您可以直接使用一个UIViewController类来初始化它。

Update:In your case:

更新：在你的情况下：

UIViewController *genericViewCon = [[UIViewController alloc] initWithNibName:@"CustomView"];
//Assuming you have a reference for the activity indicator in your custom view class
CustomView *myView = (CustomView *)genericViewCon.view;
[parentView addSubview:myView];
//And when necessary
[myView.activityIndicator startAnimating]; //or stop

Otherwise you have to make a custom UIViewController(to make it as the file's owner so that the outlets are properly wired up).

否则，您必须进行自定义UIViewController（使其成为文件的所有者，以便正确连接插座）。

YourCustomController *yCustCon = [[YourCustomController alloc] initWithNibName:@"YourXibName"].

Wherever you want to add the view you can use.

无论您想在何处添加可以使用的视图。

[parentView addSubview:yCustCon.view];

However passing the another view controller(already being used for another view) as the owner while loading the xib is not a good idea as the view property of the controller will be changed and when you want to access the original view, you won't have a reference to it.

但是，在加载 xib 时将另一个视图控制器（已用于另一个视图）作为所有者传递不是一个好主意，因为控制器的视图属性将被更改，并且当您想要访问原始视图时，您将不会有一个参考。

EDIT:You will face this problem if you have setup your new xib with file's owner as the same main UIViewControllerclass and tied the view property to the new xib view.

编辑：如果您将文件所有者设置为相同的主UIViewController类并将视图属性绑定到新的 xib 视图，您将面临此问题。

i.e;

IE;

• YourMainViewController -- manages -- mainView
• CustomView -- needs to load from xib as and when required.

• YourMainViewController -- 管理 -- mainView
• CustomView——需要在需要时从xib加载。

The below code will cause confusion later on, if you write it inside view did load of YourMainViewController. That is because self.viewfrom this point on will refer to your customview

下面的代码稍后会引起混淆，如果你把它写在 view did load of YourMainViewController. 那是因为self.view从这一点开始将引用您的自定义视图

-(void)viewDidLoad:(){
  UIView *childView= [[[NSBundle mainBundle] loadNibNamed:@"YourXibName" owner:self options:nil] objectAtIndex:0];
}