如何在 iOS 10 通知中获取应用程序状态？答案

【问题标题】：How to get Application states in iOS 10 notification?如何在 iOS 10 通知中获取应用程序状态？
【发布时间】：2017-01-25 10:52:21
【问题描述】：

我正在使用

userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response withCompletionHandler:(void(^)())completionHandler

为了在 iOS 10 中获取通知响应，谁能告诉我如何获取其中的应用程序状态？

因为在 iOS 9 或之前我使用过

application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler

在这个方法中，我们可以通过

application.applicationState

感谢您的帮助。

【问题讨论】：

标签： ios objective-c ios10 nsusernotificationcenter

【解决方案1】：

我做了一些搜索，我得到了这些方法

 - (void)userNotificationCenter:(UNUserNotificationCenter *)center  
willPresentNotification:(UNNotification *)notification withCompletionHandler:(void (^)(UNNotificationPresentationOptions options))completionHandler{  
NSLog( @"for handling push in foreground" );  
// Your code
NSLog(@"%@", notification.request.content.userInfo); //for getting response payload data
}  

- (void)userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response  withCompletionHandler:(void (^)())completionHandler   {  
NSLog( @"for handling push in background" );  
// Your code
NSLog(@"%@", notification.request.content.userInfo); //for getting response payload data 
}

【讨论】：

还有第三种状态——UIApplicationState.Inactive，与Background略有不同，即app被强制关闭时的状态。知道我们如何检查 UNUserNotificationCenter

【解决方案2】：

类似这样的：

NSString * state = @"Unknown";
UIApplication *application = [UIApplication sharedApplication];
if ( application.applicationState == UIApplicationStateInactive ) {
    //The application received the notification from an inactive state, i.e. the user tapped the "View" button for the alert.
    //If the visible view controller in your view controller stack isn't the one you need then show the right one.
    state = @"UIApplicationStateInactive";
}

if(application.applicationState == UIApplicationStateActive ) {
    //The application received a notification in the active state, so you can display an alert view or do something appropriate.
    state = @"UIApplicationStateActive";
}

if(application.applicationState == UIApplicationStateBackground ) {
    state = @"UIApplicationStateBackground";
}

【讨论】：

UIApplication *application = [[UIApplication sharedApplication].applicationState]; 这行会出错，因为[[UIApplication sharedApplication].applicationState] 将返回UIApplicationState 而不是UIApplication
当然，只是快速打字

【解决方案3】：

您可以从项目中的任何位置获取应用程序的状态，例如，

   UIApplication *applicaiton = [UIApplication sharedApplication];

if (applicaiton.applicationState  == UIApplicationStateBackground) {

    NSLog(@"background state");
}

就像你可以使用UIApplicationStateActive,UIApplicationStateInactive etc 来获取各自的状态一样

【讨论】：