Iphone XCode 我的倒计时不再显示动画

Question

嘿伙计们另一个问题！

我想再次声明，我对此很陌生，因此我对 Objective C 语言和 Xcode 应用程序的理解能力是有限的！因此，非常感谢您的帮助！

我构建了一个倒计时应用程序，显示广播电台何时上线，倒计时工作完美，每秒实时更新一次，然后我将其插入到“If-Statement”中，以便当电台启动时到达时倒计时消失，但现在我的倒计时不会实时更新，它只是静态的。

以下是我的代码：

- (void)viewDidAppear:(BOOL)animated {

        self.today = [NSDate date];
        NSDateFormatter *dateformatter = [[NSDateFormatter alloc] init];
        [dateformatter setDateFormat:@"MM/dd/yyyy hh:mm:ss"];

        NSString *launchDay = [[NSString alloc] initWithString:@"11/26/2010 11:59:59"];
        NSDate *currentDate = [dateformatter dateFromString:launchDay];

        NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
        int unitFlags = NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
        NSDateComponents *components = [gregorian components:unitFlags fromDate:today toDate:currentDate options:0];


        if ([today timeIntervalSinceDate:currentDate] <= 0 ){   
                    self.today = [NSDate date];
        NSDateFormatter *dateformatter = [[NSDateFormatter alloc] init];
        [dateformatter setDateFormat:@"MM/dd/yyyy hh:mm:ss"];
        countdownLabel.text = [NSString stringWithFormat:@"%02d:%02d:%02d:%02d", components.day, components.hour, components.minute, components.second ];
            self.timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateLabel) userInfo:nil repeats:YES];
        [self updateLabel]; 
        days.text = @"Days";
        hours.text = @"Hours";
        mins.text = @"Mins";
        secs.text = @"Secs";
        until.text = @"Until XtremeFM Launch!";
    }

    else {
        countdownLabel.text =@"XtremeFM is LIVE";

    }
}

非常感谢大家的帮助，我真的希望有人可以帮助我！

谢谢你们， Phil

好的，这是主屏幕的整个 .M 文件的代码

#import "XtremeFMViewController.h"

@implementation XtremeFMViewController



/*
// The designated initializer. Override to perform setup that is required before the view is loaded.
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) {
        // Custom initialization
    }
    return self;
}
*/

/*
// Implement loadView to create a view hierarchy programmatically, without using a nib.
- (void)loadView {
}
*/



@synthesize countdownLabel, today, timer, todayDate, days, hours, mins, secs, until;


-(void)updateLabel {
    self.today = [NSDate date];
    NSDateFormatter *dateformatter = [[NSDateFormatter alloc] init];
    [dateformatter setDateFormat:@"MM/dd/yyyy hh:mm:ss"];

    //NSString *launchDay = [[NSString alloc] initWithString:@"11/26/2010 11:59:59"];
    //NSDate *currentDate = [dateformatter dateFromString:launchDay];

    //NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    //int unitFlags = NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
    //NSDateComponents *components = [gregorian components:unitFlags fromDate:today toDate:currentDate options:0];


}

    - (void)viewDidAppear:(BOOL)animated {

        self.today = [NSDate date];
        NSDateFormatter *dateformatter = [[NSDateFormatter alloc] init];
        [dateformatter setDateFormat:@"MM/dd/yyyy hh:mm:ss"];

        NSString *fathersDay = [[NSString alloc] initWithString:@"11/26/2010 11:59:59"];
        NSDate *currentDate = [dateformatter dateFromString:fathersDay];

        NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
        int unitFlags = NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
        NSDateComponents *components = [gregorian components:unitFlags fromDate:today toDate:currentDate options:0];


        if ([today timeIntervalSinceDate:currentDate] <= 0 ){   
                    self.today = [NSDate date];
        NSDateFormatter *dateformatter = [[NSDateFormatter alloc] init];
        [dateformatter setDateFormat:@"MM/dd/yyyy hh:mm:ss"];
        countdownLabel.text = [NSString stringWithFormat:@"%02d:%02d:%02d:%02d", components.day, components.hour, components.minute, components.second ];
            self.timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateLabel) userInfo:nil repeats:YES];
        [self updateLabel]; 
        days.text = @"Days";
        hours.text = @"Hours";
        mins.text = @"Mins";
        secs.text = @"Secs";
        until.text = @"Until XtremeFM Launch!";
    }

    else {
        countdownLabel.text =@"XtremeFM is LIVE";

    }
}


- (IBAction)watchLive { 

    self.today = [NSDate date];
    NSDateFormatter *dateformatter = [[NSDateFormatter alloc] init];
    [dateformatter setDateFormat:@"MM/dd/yyyy hh:mm:ss"];
    NSString *launchDay = [[NSString alloc] initWithString:@"11/26/2010 11:59:00"];
    NSDate *currentDate = [dateformatter dateFromString:launchDay];

    //NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    //int unitFlags = NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
    //NSDateComponents *components = [gregorian components:unitFlags fromDate:today toDate:currentDate options:0];
    //countdownLabel.text = [NSString stringWithFormat:@"%02d:%02d:%02d:%02d", components.day, components.hour, components.minute, components.second ];



    if ([today timeIntervalSinceDate:currentDate] >= 0 ){

        NSString *webpage = @"http://xphiltestpagex.is.livestream-api.com/livestreamiphone/philtestpage/playlist.m3u8";
        NSURL *nswebpage = [NSURL URLWithString:webpage];
        NSURLRequest *nsurl = [NSURLRequest requestWithURL:nswebpage];
        [webView loadRequest:nsurl];

    }
    else {

        UIAlertView*alert = [[UIAlertView alloc] initWithTitle:@"Coming Soon" message:@"Feed goes live Friday 26th November 12:00pm" delegate:nil cancelButtonTitle:@"Dismiss" otherButtonTitles:nil];
        [alert show];
        [alert release];
    }


}

-(IBAction)requestsPage {
    RequestsPageViewController *move = [[RequestsPageViewController alloc]initWithNibName:nil bundle:nil];
    move.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
    [self presentModalViewController:move animated:YES];
    [move release];
}

-(IBAction)twitterButton {
    RequestsPageViewController *move = [[RequestsPageViewController alloc]initWithNibName:nil bundle:nil];
    move.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
    [self presentModalViewController:move animated:YES];
    [move release];
}


/*
// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
*/

- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}


- (void)dealloc {
    [super dealloc];
}

@end

，请参阅我在 ViewDidAppear 上有一个 (BOOL) 动画，但我不知道如何将其添加到 if 语句中（Noob ）

Answer 1

我发现 NSLog() 对于追踪未正确触发条件的事物非常有用。

紧接在 if() 之前，执行：

NSLog(@"%d", [today timeIntervalSinceDate:currentDate]);

然后查看控制台上显示的内容。

我搞砸了这类事情的一个地方是以错误的顺序测试这些值，所以我期望的负值是正值，反之亦然。

此外，您几乎泄漏了在该代码中分配的所有内容。请返回并<​​code>释放您分配的所有内容！