ios - 如何从框架中调配 AppDelegate 的 didReceiveRemoteNotification

Question

我正在为 iOS 应用程序（一个 pod）开发一个框架。我想调酒

application(_:didReceiveRemoteNotification:fetchCompletionHandler:)

使用我的框架中定义的方法。这是我的代码：

class MyClass {
    @objc
    func myCustomizedMethod(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
        // my code
    }

    private func swizzleDidReceiveRemoteNotification() {
        guard let appDelegateClass = object_getClass(UIApplication.shared.delegate) else { return }

        let originalSelector = #selector((appDelegateClass as! UIApplicationDelegate).application(_:didReceiveRemoteNotification:fetchCompletionHandler:))
        let swizzledSelector = #selector(MyClass.self.myCustomizedMethod(_:didReceiveRemoteNotification:fetchCompletionHandler:))

        guard let originalMethod = class_getInstanceMethod(appDelegateClass, originalSelector) else { return }
        guard let swizzledMethod = class_getInstanceMethod(MyClass.self, swizzledSelector) else { return }

        method_exchangeImplementations(originalMethod, swizzledMethod)
    }
}

但是当我运行我的代码时，似乎 originalMethod 的值为零，所以

class_getInstanceMethod(appDelegateClass, originalSelector)

返回零。我做错了什么？（请考虑我无权访问 AppDelegate，因为正如我所说，我正在开发一个框架）

Answer 1

该方法是可选的。如果它不存在，那么您必须添加它而不是扩展实现。

Answer 2

这是对我有用的代码：

class MyClass {
    @objc
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
        // my code
    }

    private func swizzleDidReceiveRemoteNotification() {
        let appDelegate = UIApplication.shared.delegate
        let appDelegateClass = object_getClass(appDelegate)

        let originalSelector = #selector(UIApplicationDelegate.application(_:didReceiveRemoteNotification:fetchCompletionHandler:))
        let swizzledSelector = #selector(MyClass.self.application(_:didReceiveRemoteNotification:fetchCompletionHandler:))

        guard let swizzledMethod = class_getInstanceMethod(MyClass.self, swizzledSelector) else {
            return
        }

        if let originalMethod = class_getInstanceMethod(appDelegateClass, originalSelector)  {
            // exchange implementation
            method_exchangeImplementations(originalMethod, swizzledMethod)
        } else {
            // add implementation
            class_addMethod(appDelegateClass, swizzledSelector, method_getImplementation(swizzledMethod), method_getTypeEncoding(swizzledMethod))
        }
    }
}