如何在 Swift 的标签栏项目中设置图像？

Question

我采用了一个视图控制器并将其嵌入到导航控制器中，并且它再次嵌入到了标签栏控制器中。当我尝试通过故事板设置图像时，图像不会出现在标签栏图标上。这里的图片名称是 25。

我能做什么？我怎样才能以编程方式做到这一点？为此，我应该采取什么合适的图像尺寸？

Answer 1

设置两个图像 - 用于选择/选定状态

Answer 2

添加 AppDelegate 类：

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool
{
    window=UIWindow(frame: UIScreen.main.bounds)
    self.window?.rootViewController = setTabbar()
    self.window?.makeKeyAndVisible()
    window?.backgroundColor=UIColor.white
    return true
}

func setTabbar() -> UITabBarController
{
    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    let tabbarcntrl = UITabBarController()

    let Home = storyboard.instantiateViewController(withIdentifier: "HomeView") // 1st tab bar viewcontroller
    let Followed = storyboard.instantiateViewController(withIdentifier: "FollowedView") // 2nd tab bar viewcontroller
    let Message = storyboard.instantiateViewController(withIdentifier: "MessageView") // 3rd tab bar viewcontroller

    // all viewcontroller embedded navigationbar
    let nvHome = UINavigationController(rootViewController: Home)
    let nvFollowed = UINavigationController(rootViewController: Followed)
    let nvMessage = UINavigationController(rootViewController: Message)

    // all viewcontroller navigationbar hidden
    nvHome.setNavigationBarHidden(true, animated: false)
    nvFollowed.setNavigationBarHidden(true, animated: false)
    nvMessage.setNavigationBarHidden(true, animated: false)

    tabbarcntrl.viewControllers = [nvHome,nvFollowed,nvMessage]

    let tabbar = tabbarcntrl.tabBar
    tabbar.barTintColor = UIColor.black
    tabbar.backgroundColor = UIColor.black
    tabbar.tintColor = UIColor(red: 43/255, green: 180/255, blue: 0/255, alpha: 1)

    //UITabBar.appearance().tintColor = UIColor.white
    let attributes = [NSFontAttributeName:UIFont(name: "Montserrat-Light", size: 10)!,NSForegroundColorAttributeName:UIColor.white]
    let attributes1 = [NSFontAttributeName:UIFont(name: "Montserrat-Light", size: 10)!,NSForegroundColorAttributeName:UIColor(red: 43/255, green: 180/255, blue: 0/255, alpha: 1)]

    UITabBarItem.appearance().setTitleTextAttributes(attributes, for: .normal)
    UITabBarItem.appearance().setTitleTextAttributes(attributes1, for: .selected)


    let tabHome = tabbar.items![0]
    tabHome.title = "Home" // tabbar titlee
    tabHome.image=UIImage(named: "icon_home.png")?.withRenderingMode(.alwaysOriginal) // deselect image
    tabHome.selectedImage = UIImage(named: "icon_home.png")?.withRenderingMode(.alwaysOriginal) // select image
    tabHome.titlePositionAdjustment.vertical = tabHome.titlePositionAdjustment.vertical-4 // title position change

    let tabFoll = tabbar.items![1]
    tabFoll.title = "Followed"
    tabFoll.image=UIImage(named: "icon_fold.png")?.withRenderingMode(.alwaysOriginal)
    tabFoll.selectedImage=UIImage(named: "icon_fold.png")?.withRenderingMode(.alwaysOriginal)
    tabFoll.titlePositionAdjustment.vertical = tabFoll.titlePositionAdjustment.vertical-4

    let tabMsg = tabbar.items![3]
    tabMsg.title = "Message"
    tabMsg.image=UIImage(named: "icon_mail.png")?.withRenderingMode(.alwaysOriginal)
    tabMsg.selectedImage=UIImage(named: "icon_mail.png")?.withRenderingMode(.alwaysOriginal)
    tabMsg.titlePositionAdjustment.vertical = tabMsg.titlePositionAdjustment.vertical-4

    return tabbarcntrl
}

Answer 3

您正在以正确的方式做所有事情但唯一的问题是您的 tabbaritem 图像大小不正确。请查看此表以了解 tabbaritem 图像的实际大小。

Answer 4

在您的 MainTabbarViewController 中

绑定标签栏的出口：

@IBOutlet weak var myTabBar: UITabBar?
 
 override func viewDidLoad() {
      super.viewDidLoad()
      
      myTabBar?.tintColor = UIColor.white
      tabBarItem.title = ""
      
      setTabBarItems()
      
 }

设置tabbar项在这里定义的方法如下：

func setTabBarItems(){
      
      let myTabBarItem1 = (self.tabBar.items?[0])! as UITabBarItem
      myTabBarItem1.image = UIImage(named: "Unselected")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem1.selectedImage = UIImage(named: "Selected ")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem1.title = ""
      myTabBarItem1.imageInsets = UIEdgeInsets(top: 6, left: 0, bottom: -6, right: 0)
      
      let myTabBarItem2 = (self.tabBar.items?[1])! as UITabBarItem
      myTabBarItem2.image = UIImage(named: "Unselected")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem2.selectedImage = UIImage(named: "Selected")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem2.title = ""
      myTabBarItem2.imageInsets = UIEdgeInsets(top: 6, left: 0, bottom: -6, right: 0)
      
      
      let myTabBarItem3 = (self.tabBar.items?[2])! as UITabBarItem
      myTabBarItem3.image = UIImage(named: "Unselected")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem3.selectedImage = UIImage(named: "Selected")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem3.title = ""
      myTabBarItem3.imageInsets = UIEdgeInsets(top: 6, left: 0, bottom: -6, right: 0)
      
      let myTabBarItem4 = (self.tabBar.items?[3])! as UITabBarItem
      myTabBarItem4.image = UIImage(named: "Unselected")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem4.selectedImage = UIImage(named: "Selected")?.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
      myTabBarItem4.title = ""
      myTabBarItem4.imageInsets = UIEdgeInsets(top: 6, left: 0, bottom: -6, right: 0)
      
 }

Answer 5

在 swift 4 和 5 中，您可以使用以下扩展。记住一件事总是传递相同数量的图像、选定的图像和标题，但如果您不想设置标题，则在标题中传递 nil。

extension UITabBarController{        
        func setUpImagaOntabbar(_ selectedImage : [UIImage], _ image : [UIImage], _ title : [String]?){
            
            for (index,vals) in image.enumerated(){
                
                if let tab = self.tabBar.items?[index]{
                    
                    tab.image = image[index]
                    tab.image = selectedImage[index]
                    if let tile = title[index]{
                       tab.title = title[index]
                      }
                    
                }
            }
        }
    }