appdelegate.m ファイルで以下のコードを使用します
メソッドの下に置く
-(void)minCalculation_backgroundtime:(NSString *)backgroundTime forgroundTime:(NSString *)foreGroundTime
{
NSDateFormatter *dateformat = [[NSDateFormatter alloc]init];
[dateformat setDateFormat:@"MM/dd/yyyy HH:mm:ss"];
NSDate *lastDate = [dateformat dateFromString:foreGroundTime];
NSDate *todaysDate = [dateformat dateFromString:backgroundTime];
NSTimeInterval lastDiff = [lastDate timeIntervalSinceNow];
NSTimeInterval todaysDiff = [todaysDate timeIntervalSinceNow];
NSTimeInterval dateDiff = lastDiff - todaysDiff;
int min = dateDiff/60;
NSLog(@"Good to see you after %i minutes",min);
}
以下の2つの方法を置き換えます
- (void)applicationDidEnterBackground:(UIApplication *)application
{
NSDateFormatter *dateFormat = [[NSDateFormatter alloc]init];
[dateFormat setDateFormat:@"MM/dd/yyyy HH:mm:ss"];
NSString *backGroundTime = [dateFormat stringFromDate:[NSDate date]];
[[NSUserDefaults standardUserDefaults]setValue:backGroundTime forKey:@"backGroundTime"];
// 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.
}
- (void)applicationWillEnterForeground:(UIApplication *)application
{
NSDateFormatter *dateFormat = [[NSDateFormatter alloc]init];
[dateFormat setDateFormat:@"MM/dd/yyyy HH:mm:ss"];
NSString *foreGroundTime = [dateFormat stringFromDate:[NSDate date]];
NSString *backGroundTime = [[NSUserDefaults standardUserDefaults]valueForKey:@"backGroundTime"];
[self minCalculation_backgroundtime:backGroundTime forgroundTime:foreGroundTime];
// Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
}
これを試してみてくださいあなたの問題は解決します