问题描述
在 AppDelegate 中，每当收到 VoIP 呼叫(推送通知)时，都会调用以下函数，从而创建多个VideoCallViewController"实例
In AppDelegate, the below function gets called whenever VoIP call (push notification) is received thereby creating multiple instances of "VideoCallViewController"
如下所示，我使用 deinit(在 VideoCallViewController 中)来检查是否在创建新的VideoCallViewController"实例之前取消了先前的VideoCallViewController"实例，令我惊讶的是 print("Deinitializing VC) 未被调用，将实例留在内存中.
I've used deinit (in VideoCallViewController) as shown below, to check if the previous instance of "VideoCallViewController" was being de-initialised before a new instance of "VideoCallViewController" is created, to my surprise print("Deinitializing VC) wasn't called, leaving the instance in memory.
如果 AppDelegate 中已经存在 VideoCallViewController 的实例，我如何显示 VideoCallViewController 及其导航控制器.
How can I show VideoCallViewController with its Navigation Controller if an instance of VideoCallViewController already exists from AppDelegate.
在 VideoCallViewController 中
deinit {
print("Deinitializing VC)
}
在 AppDelegate 中
func pushRegistry(_ registry: PKPushRegistry, didReceiveIncomingPushWith payload: PKPushPayload, forType type: PKPushType) {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
videoVC = storyboard.instantiateViewController(withIdentifier: "VideoCallViewController") as! VideoCallViewController
self.window = UIWindow(frame: UIScreen.main.bounds)
self.window?.rootViewController = videoVC
self.window?.makeKeyAndVisible()
}
推荐答案
可能的解决方案:创建单例持有对可空窗口的引用，负责视频通话流程.在通知更改可见窗口.通话结束 - 返回应用程序主窗口.
Possible solution: Create singleton holding reference to nullable window, responsible for video calls flow. On notification change visible windows. On call end - return to the application main window.
例如:
class VideoCallManager {
//MARK: - Singleton
static let sharedInstance = VideoCallManager()
private init() {}
private var videoCallWindow: UIWindow?
func navigateToVideoCallViewController() {
if let window = self.videoCallWindow, window.keyWindow {
//VideoCallViewController is displayed at the moment.
return
}
videoCallWindow = UIWindow.init(frame: UIScreen.mainScreen().bounds)
let storyboard = UIStoryboard(name: "Main", bundle: nil)
videoVC = storyboard.instantiateViewController(withIdentifier: "VideoCallViewController") as! VideoCallViewController
self.videoCallWindow?.rootViewController = videoVC
self.videoCallWindow?.makeKeyAndVisible()
}
func returnToWindowOfAppDelegate() {
if let window = self.videoCallWindow, window.keyWindow {
(UIApplication.sharedApplication().delegate as? AppDelegate)?.window?.makeKeyAndVisible()
self.videoCallWindow = nil
}
}
}
你的方法看起来像:
func pushRegistry(_ registry: PKPushRegistry, didReceiveIncomingPushWith payload: PKPushPayload, forType type: PKPushType) {
VideoCallManager.sharedInstance.navigateToVideoCallViewController()
}
这篇关于避免创建多个 ViewController 实例，iOS Swift的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！