如何在 iOS 7 中超过 180 秒在后台运行 NSTimer？
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How to run NSTimer in background beyond 180sec in iOS 7?
提问by Deepak Gupta
I have tried this but not working more than 180 sec in iOS 7 and Xcode 4.6.2. Please help me
我已经尝试过这个，但在 iOS 7 和 Xcode 4.6.2 中工作时间不超过 180 秒。请帮我
UIBackgroundTaskIdentifier bgTask = UIBackgroundTaskInvalid;
UIApplication *app = [UIApplication sharedApplication];
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask];
}];
NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:20 target:self selector:@selector(timerMethod) userInfo:nil repeats:YES];
[[NSRunLoop currentRunLoop] addTimer:timer forMode:NSRunLoopCommonModes];
-(void) timerMethod{
NSLog(@"in timerMethod");
}
回答by Tarek Hallak
Unless you enable one of the Background modes, it is not gonna work.
除非您启用其中之一，否则Background modes它将无法正常工作。
Why?
为什么？
You have around 10 minutes of background execution after this the timer is stopped by ios.
The timer will not fire after app is locked (iOS7), since ios suspends the foreground app and
bgTaskwill not get fire again.
在此计时器被 ios 停止之后，您有大约 10 分钟的后台执行时间。
应用程序被锁定（iOS7）后计时器不会触发，因为 ios 挂起前台应用程序并且
bgTask不会再次触发。
There is some workarounds, consider to check below question:
有一些解决方法，请考虑检查以下问题：
iphone - NSTimers in background
Scheduled NSTimer when app is in background?
