如何让我的应用程序在后台运行？

Question

我正在开发一个警报应用程序。我在我的应用程序中使用NSTimer。计时器工作得很好。但是当我最小化应用程序时，计时器停止工作。如何在应用程序关闭或最小化时使其工作？

这是我的代码

- (void) alarmSaveButtonAction:(id)sender {


timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self
                                       selector:@selector(onTimerEvent)
                                       userInfo:nil repeats:YES];  
}
-(void)onTimerEvent
{
    NSLog(@"saravanan");
    NSDate *now = [NSDate new]; 

    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    dateFormatter.dateFormat = @"hh:mm:ss a";
    [dateFormatter setTimeZone:[NSTimeZone systemTimeZone]];
    NSLog(@"The Current Time is %@",[dateFormatter stringFromDate:now]);
    NSString *string2 = [NSString stringWithFormat:[dateFormatter stringFromDate:now]];
    NSLog(@"currenttime %@", string2);
    [dateFormatter release];


    Resource *resourceLoader = [[Resource alloc] init];

    NSDictionary *prefDic = [resourceLoader getPlistDataAsDictionary:@"preference"];

    NSDate *selectedDateTime = [[NSDate alloc]init];

    selectedDateTime = [prefDic objectForKey:@"alarmtime"];

    NSDateFormatter *dateFormatter1 = [[NSDateFormatter alloc] init];
    dateFormatter1.dateFormat = @"hh:mm:ss a";
    [dateFormatter1 setTimeZone:[NSTimeZone systemTimeZone]];
    NSLog(@"saravanan date %@",[dateFormatter1 stringFromDate:selectedDateTime]);
    NSString *string1 = [NSString stringWithFormat:[dateFormatter1 stringFromDate:selectedDateTime]];
    NSLog(@"currenttime %@", string1);
    [dateFormatter1 release];


    if ([string1 isEqualToString:string2]) 
    {
        NSLog(@"alarm scheduld");
        [self scheduledNotification];
        [timer invalidate];
        timer = nil;
    }
}

提前致谢。

Answer 1

警报使用预定的本地notifications。

Answer 2

你不能这样做，至少在公共API和应用商店规则的范围内不能这样做。