// 显示指示器

    MBProgressHUD *HUD = [MBProgressHUDshowHUDAddedTo:[[UIApplicationsharedApplication].windowsobjectAtIndex:1]animated:YES];

    [self.view.windowaddSubview:HUD];

    HUD.labelText =@“正在加载中...”;

   加载完成后，调用[HUD hide:YES];隐藏