如何防止扩展导出到Objective-C的Swift头？

Question

我在Swift中做了这个简单的扩展:

extension DispatchQueue {
    func asyncAfter(delay: TimeInterval, block: @escaping ()->()) {
        DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + Double(Int64(delay * Double(NSEC_PER_SEC))) / Double(NSEC_PER_SEC), execute: block)
    }
}

在Project-Swift.h头文件中,它报告此行的错误:

@interface OS_dispatch_queue (SWIFT_EXTENSION(...))
- (void)asyncAfterDelay:(NSTimeInterval)delay block:(void (^ _Nonnull)(void))block;
@end

错误是:找不到'OS_dispatch_queue'的接口声明

有没有办法阻止为Objective-C导出扩展？或者有办法解决错误吗？

Answer 1

您可以在或@objc之前使用来防止导出为 Objective-C，如下所示。funcmethod

extension DispatchQueue {
    @objc func asyncAfter(delay: TimeInterval, block: @escaping ()->()) {
        DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + Double(Int64(delay * Double(NSEC_PER_SEC))) / Double(NSEC_PER_SEC), execute: block)
    }
}