防止程序输入时候产生错误后，锁定屏幕崩溃

2019独角兽企业重金招聘Python工程师标准>>>

- (void)applicationDidEnterBackground:(UIApplication *)application{
    // Use this method to release shared resources, save user data,
    // invalidate timers, and store enough application state information to 
    // restore your application to its current state in case it is terminated later.
    // If your application supports background execution,
    //  this method is called instead of applicationWillTerminate: when the user quits.
    if (([[[UIDevice currentDevice] systemVersion] floatValue] >= 6.0))
    {
        // Acquired additional time
        UIDevice *device = [UIDevice currentDevice];
        BOOL backgroundSupported = NO;
        if ([device respondsToSelector:@selector(isMultitaskingSupported)])
        {
            backgroundSupported = device.multitaskingSupported;
        }
        if (backgroundSupported)
        {
            backgroundTask = [application beginBackgroundTaskWithExpirationHandler:^{
            [application endBackgroundTask:backgroundTask];
            backgroundTask = UIBackgroundTaskInvalid;
            }];
        }
    }
    return;
}

其中的backgroundTask 是成员变量。

转载于:https://my.oschina.net/dourgulf/blog/104613