Question

目前在我的AppDelegate.m我有代码：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    [self.window makeKeyAndVisible];
    CGRect  rect = [[UIScreen mainScreen] bounds];
    UIImageView *imageView =[[UIImageView alloc] initWithFrame:rect];
    imageView.animationImages = [NSArray arrayWithObjects:
                                 [UIImage imageNamed:@"Comp 2_00000.png"],..., nil];
    imageView.animationDuration = 6;
    imageView.animationRepeatCount = 1;
    [imageView startAnimating];
    [self.window addSubview:imageView];

    return YES;
}

当我的视图在我的ViewController.m中加载代码时，我播放动画已经加载了一些大约5秒的数据。

我使用JSON和URLS加载这样的数据：

 NSURL *url = [NSURL URLWithString:@"http://xxxxxxxx.co.uk/untitled%20folder/jsonimages.php"];
    NSData *jsonData = [NSData dataWithContentsOfURL:url];
    NSError *error = nil;

    NSDictionary *result = [NSJSONSerialization JSONObjectWithData:jsonData
                                                           options:NSJSONReadingMutableContainers error:&error];

在数据加载时是否有动画播放？

Answer 1

您可以做的是分派数据请求，然后调用动画：

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    NSURL *url = [NSURL URLWithString:@"http://xxxxxxxx.co.uk/untitled%20folder/jsonimages.php"];
    NSData *jsonData = [NSData dataWithContentsOfURL:url];
    NSError *error = nil;

    NSDictionary *result = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers error:&error];
        dispatch_async(dispatch_get_main_queue(), ^{
              //Main thread stuff, after loading the data
              [self animate];
        });
});

...

- (void)animate {
    CGRect  rect = [[UIScreen mainScreen] bounds];
    UIImageView *imageView =[[UIImageView alloc] initWithFrame:rect];
    imageView.animationImages = [NSArray arrayWithObjects:
                                 [UIImage imageNamed:@"Comp 2_00000.png"],..., nil];
    imageView.animationDuration = 6;
    imageView.animationRepeatCount = 1;
    [imageView startAnimating];
    [self.view addSubview:imageView];
}

Answer 2

创建辅助函数（如果需要重用它，请将其设置为静态）：

<强>功能：

-(UIImageView *) InitImageView{    
    [self.window makeKeyAndVisible];
    CGRect  rect = [[UIScreen mainScreen] bounds];
    UIImageView *imageView =[[UIImageView alloc] initWithFrame:rect];
    imageView.animationImages = [NSArray arrayWithObjects:
                           [UIImage imageNamed:@"Comp 2_00000.png"],..., nil];
    //imageView.animationDuration = 6;
    imageView.animationRepeatCount = 1;

    [self.view addSubview:imageView];

    return imageView;
}

Ansynchronous Task：

//Start Animation
UIImageView *imageView = [self InitImageView];
[imageView startAnimating];

dispatch_queue_t queue = dispatch_queue_create("co.uk.bits.bots", NULL);
dispatch_async(queue, ^{
 NSURL *url = [NSURL URLWithString:@"http://xx.co.uk/jsonimages.php"];
    NSData *jsonData = [NSData dataWithContentsOfURL:url];
    NSError *error = nil;

    NSDictionary *result = [NSJSONSerialization JSONObjectWithData:jsonData
                         options:NSJSONReadingMutableContainers error:&error];
    dispatch_async(dispatch_get_main_queue(), ^{
        //Stop Animation
        [imageView stopAnimating];
    });
});

Answer 3

此代码可能会使您的应用从应用商店中被拒绝，因为它会强制用户在每次启动应用时等待六秒钟。 Apple的指导方针表示，应用程序的发布应该尽快发布。

你能不能重构它，这样你的初始视图控制器可以在没有数据的情况下显示，然后在数据可用时逐步更新它？

如果从网络加载数据，您也可以对其进行缓存，以便后续启动更快。

在加载数据时播放动画

3 个答案: