是否可以从同一项目的Swift类调用目标C应用程序委托方法？

Question

I'm merging my Swift project with already existing Objective-C code. I need to call some important methods of Swift class from objective C app delegate. I tried all methods given in net, but it was no use. Can any one help me out?

Answer 1

Yes, it's possible but with some limitations.

You can use only classes which inherited from NSObject, with public attribute and marked with @objc. At Objective-C code you should import "ProductModuleName-Swift.h" file which generated by compiler.

Here is an example of Swift class:

import Foundation

@objc public class ExampleClass: NSObject {
    @objc public var someInstanceProperty = "Property"

    @objc public func someFunction() {
        print("Some function")
    }
}

Notice that this class inherited from NSObject and have @objc and public attributes. After command+B you can take a look at generated bridge header through Assistance editor:

Then you should import the bridge header at your Objective-C class.

#import "ProductModuleName-Swift.h"

And then you can use your Swift class at Objective-C code like any other Objective-C class:

__auto_type const someClass = [ExampleClass new];
[someClass someFunction];
NSLog(@"%@", someClass.someInstanceProperty);

Here is an additional information from Apple: Importing Swift into Objective-C