blocks|key|1922816|text|你可以的。您所需要的只是创建一个桥接目标C头。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1922817|每苹果文档|offset|length|1922818|要在与Swift代码相同的应用程序目标中导入一组Objective文件，您需要依赖Objective桥接头将这些文件公开给Swift。Xcode提供了在将Swift文件添加到现有的Objective应用程序或将Objective文件添加到现有的Swift应用程序时创建这个头文件的功能。|blockquote|1922819|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.apple.com/library/ios/documentation/Swift/Conceptual/BuildingCocoaApps/MixandMatch.html^0|0|1|4|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@]|9|@$D|S|E|T|1|U]]|A|$]]|$1|F|3|G|5|H|7|V|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|J|$K|$5|L|M|N|A|$O|P]]]]

You can. All you need is to create a bridging objective C header.

Per <a href="https://developer.apple.com/library/ios/documentation/Swift/Conceptual/BuildingCocoaApps/MixandMatch.html" rel="nofollow">Apple Documentation</a>:

<blockquote>
 To import a set of Objective-C files in the same app target as your
 Swift code, you rely on an Objective-C bridging header to expose those
 files to Swift. Xcode offers to create this header file when you add a
 Swift file to an existing Objective-C app, or an Objective-C file to
 an existing Swift app.
</blockquote>

blocks|key|1368741|text|只需创建一个桥接头文件，然后在其中导入ObjC文件，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1368742|#import+<objectivec.h>|code-block|syntax|javascript|1368743|稍后在你的快速档案中：|1368744|var+a+=+objectivec()
a.method_from_those_file|1368745|欲了解更多信息，请参阅这里中的Apple。|offset|length|1368746|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.apple.com/library/ios/documentation/Swift/Conceptual/BuildingCocoaApps/MixandMatch.html^0|0|0|0|0|B|2|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|10|8|@]|9|@$M|11|N|12|1|13]]|A|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

Just create a Bridging-Header file and later import your ObjC file in it, like:

<pre><code>#import &lt;objectivec.h&gt;
</code></pre>

Later in your swift file:

<pre><code>var a = objectivec()
a.method_from_those_file
</code></pre>

For more information read Apple Doucmentation from <a href="https://developer.apple.com/library/ios/documentation/Swift/Conceptual/BuildingCocoaApps/MixandMatch.html" rel="nofollow">here</a>.

blocks|key|761759|text|我认为你不能从分机访问私有财产。您的scrollView属性位于.m文件中，而不是.h中--这意味着它是私有的，并且在扩展名文件中不可见。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|761760|解决方案:移动|761761|@property+(strong,+nonatomic)+UIScrollView+*scrollView;|code-block|syntax|javascript|761762|到你的头文件。|761763|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I think that you can't access private properties from extension. Your scrollView property is in .m file, not .h - which means it's private and it's not visible from extension file. 

Solution: move

<pre><code>@property (strong, nonatomic) UIScrollView *scrollView;
</code></pre>

to your header file.

blocks|key|1368792|text|在Swift中，私有属性无法从其他文件访问。这是private在Swift中的意思。例如：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1368793|file1.迅速的|BOLD|1368794|class+MyClass+{
++++private+var+privateProperty:+String+=+"Can't+get+to+me+from+another+file!"
}
extension+MyClass:+CustomStringConvertible+{
++++var+description:+String+{
++++++++return+"I+have+a+`var`+that+says:+\(privateProperty)"
++++}
}|code-block|syntax|javascript|1368795|文件2.快速的|1368796|extension+MyClass+{
++++func+cantGetToPrivateProperties()+{
++++++++self.privateProperty+//+Value+of+type+'MyClass'+has+no+memeber+'privateProperty'
++++}
}|1368797|在Objective类的实现中声明的属性是私有属性。因此，不能从Swift扩展名访问该属性，因为这必须来自不同的(.swift)文件.|1368798|entityMap^0|O|7|0|0|9|0|0|0|7|0|0|1L|6|0^^$0|@$1|2|3|4|5|6|7|V|8|@$9|W|A|X|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Y|8|@$9|Z|A|10|B|H]]|D|@]|E|$]]|$1|I|3|J|5|K|7|11|8|@]|D|@]|E|$L|M]]|$1|N|3|O|5|6|7|12|8|@$9|13|A|14|B|H]]|D|@]|E|$]]|$1|P|3|Q|5|K|7|15|8|@]|D|@]|E|$L|M]]|$1|R|3|S|5|6|7|16|8|@$9|17|A|18|B|C]]|D|@]|E|$]]|$1|T|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|U|$]]

In Swift, private properties are not accessible from another file. This is the meaning of <code>private</code> in Swift. For example: 

file1.swift

<pre><code>class MyClass {
 private var privateProperty: String = "Can't get to me from another file!"
}
extension MyClass: CustomStringConvertible {
 var description: String {
 return "I have a `var` that says: \(privateProperty)"
 }
}
</code></pre>

file2.swift

<pre><code>extension MyClass {
 func cantGetToPrivateProperties() {
 self.privateProperty // Value of type 'MyClass' has no memeber 'privateProperty'
 }
}
</code></pre>

A property declared in the implementation of an Objective-C class is a private property. As such, the property cannot be accessed from a Swift extension since this will be necessarily from a different (<code>.swift</code>) file...

blocks|key|761823|text|如果在单独的头中声明objc类扩展并在桥接标头中包含该标头，则可以访问内部objc属性和方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|761824|MyClass.h|offset|length|style|BOLD|761825|@interface+MyClass+:+NSObject

@property+(nonatomic,+copy,+readonly)+NSString+*string;

@end|code-block|syntax|javascript|761826|MyClass%2BPrivate.h|761827|#import+"MyClass.h"

@interface+MyClass+()

@property+(nonatomic,+copy)+NSString+*string;

@end|761828|MyClass.m|761829|#import+"MyClass%2Bprivate.h"

@implementation+MyClass

//...

@end|761830|Project-Bridging-Header.h|761831|#import+"MyClass.h"
#import+"MyClass%2BPrivate.h"|761832|entityMap^0|0|0|9|0|0|0|H|0|0|0|9|0|0|0|P|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|11|8|@$D|12|E|13|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|14|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|15|8|@$D|16|E|17|F|G]]|9|@]|A|$]]|$1|O|3|P|5|J|7|18|8|@]|9|@]|A|$K|L]]|$1|Q|3|R|5|6|7|19|8|@$D|1A|E|1B|F|G]]|9|@]|A|$]]|$1|S|3|T|5|J|7|1C|8|@]|9|@]|A|$K|L]]|$1|U|3|V|5|6|7|1D|8|@$D|1E|E|1F|F|G]]|9|@]|A|$]]|$1|W|3|X|5|J|7|1G|8|@]|9|@]|A|$K|L]]|$1|Y|3|-4|5|6|7|1H|8|@]|9|@]|A|$]]]|Z|$]]

You can access internal objc properties and methods if you declare the objc class extension in a separate header and include that header in the bridging header.

MyClass.h

<pre><code>@interface MyClass : NSObject

@property (nonatomic, copy, readonly) NSString *string;

@end
</code></pre>

MyClass+Private.h

<pre><code>#import "MyClass.h"

@interface MyClass ()

@property (nonatomic, copy) NSString *string;

@end
</code></pre>

MyClass.m

<pre><code>#import "MyClass+private.h"

@implementation MyClass

//...

@end
</code></pre>

Project-Bridging-Header.h

<pre><code>#import "MyClass.h"
#import "MyClass+Private.h"
</code></pre>

I started writing Swift extensions on my view controllers. So I have three files right now:

My header file, <code>ViewController.h</code>:

<pre><code>@interface MyViewController : UIViewController

@end
</code></pre>

My Obj-C implementation file, <code>ViewController.m</code>:

<pre><code>@interface MyViewController () &lt;UIScrollViewDelegate&gt;
@property (strong, nonatomic) UIScrollView *scrollView;
@end

@implementation MyViewController

- (void)viewDidLoad {

 [super viewDidLoad];

 self.scrollView = [[UIScrollView alloc] init];
 [self customiseScrollView]; //This is Swift method called from Obj-C file
}

@end
</code></pre>

And finally, <code>ViewController.swift</code>:

<pre><code>extension MyViewController {

 func customiseScrollView() {

 }
}
</code></pre>

My question is, is it possible to access my Obj-C properties from my Swift implementation file? Every time I refer to it, I got an error:

<pre><code>Value of type 'MyViewController' has no member 'scrollView'
</code></pre>

Bonus 1: Can someone also clarify if the Swift component can see what the .m is a delegate of as well. (To clarify, doing <code>scrollView.delegate = self</code> in Swift is a compile error because the Swift file does not realise that the .m file is a UIScrollViewDelegate).

Bonus 2: Can Swift extension file call Obj-C methods that are declared from the .m counterpart?

Accessing Obj-C properties in Swift extension file

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我开始在视图控制器上编写Swift扩展。所以我现在有三个文件：我的头文件，ViewController.h@interface MyViewController : UIViewController@end我的Obj实现文件，ViewController.m@interface MyViewController () ...

问在Swift扩展文件中访问Obj-C属性
EN

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问在Swift扩展文件中访问Obj-C属性EN