应用程序启动时的 UIActivityIndi​​cator

Question

我已经搜索过，但没有找到我想要的东西。我有一个 UITabBar 应用程序，在第一个视图中，它从网络加载大量数据。这可能需要几秒钟的时间，尤其是在连接到边缘网络时。

我有一个显示徽标等的启动屏幕，但我想添加一个活动指示器以向用户显示实际正在发生的事情。

我怎样才能实现这个目标？我发现的帖子只在选项卡之间切换时考虑 ActivityIndi​​cators。

谢谢

Answer 1

如果加载数据需要很长时间，您可以使用另一个视图控制器作为 rootViewController，只需具有启动屏幕（具有在下载数据之前可以显示的图像或视图的屏幕）和活动指示器，当您下载完成时，删除temprootViewcontroller 从窗口并将原始控制器添加到窗口。

编辑

    //To show custom Splash screen do something like in
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

SplashScreenVC *splashScreenVC = [[SplashScreenVC alloc] initWithNibName:@"SplashScreenVC" bundle:nil];
    self.window.rootViewController = splashScreenVC;
    [self.window makeKeyAndVisible];

//And when your data finishes downloading you can write following there to show your tabBar.

AppDelegate*delegate = (AppDelegate*)[UIApplication sharedApplication].delegate;
delegate.window.rootViewController = delegate.tabBarController;
[delegate.window makeKeyAndVisible];

//If you want to simulate downloading and want to sleep the device you can try this in SplashScreenVC

-(void)viewDidAppear:(BOOL)animated{
        [super viewDidAppear:animated];
        [self performSelector:@selector(gotosleep) withObject:nil afterDelay:1.0];
    }
    -(void)gotosleep{
        sleep(5);
        AppDelegate*delegate = (AppDelegate*)[UIApplication sharedApplication].delegate;
        delegate.window.rootViewController = delegate.tabBarController;
        [delegate.window makeKeyAndVisible];
    }