如何讓自定義標籤欄顯示在Xcode中設置的標籤欄項目的選定圖像？

Question

我創建了一個正確顯示標籤欄項目的自定義標籤欄。當我選擇一個選項卡/圖標時，顯示選項卡欄項目的視圖控制器，但該圖標不會更改爲「選定圖像」圖標，即圖標在顯示其視圖控制器時不會更改。

我在做什麼錯？如何將圖標更新爲我在IB上設置的圖像作爲選定的圖像？

下面是我的一些代碼：

class CustomTabBarController: UITabBarController, CustomTabBarDataSource, CustomTabBarDelegate { 
override func viewDidLoad() { 
    super.viewDidLoad() 
    self.tabBar.isHidden = true 
    let customTabBar = CustomTabBar(frame: self.tabBar.frame) 
    customTabBar.datasource = self 
    customTabBar.delegate = self 
    customTabBar.setup() 
    self.view.addSubview(customTabBar) 
} 
// MARK: - CustomTabBarDataSource 
func tabBarItemsInCustomTabBar(_ tabBarView: CustomTabBar) -> [UITabBarItem] { 
    return tabBar.items! 
} 
// MARK: - CustomTabBarDelegate 
func didSelectViewController(_ tabBarView: CustomTabBar, atIndex index: Int) { 
    self.selectedIndex = index 
} 
} 


class CustomTabBar: UIView { 
var tabBarItems: [UITabBarItem]! 
var customTabBarItems: [CustomTabBarItem]! 
var tabBarButtons: [UIButton]! 

func setup() { 
tabBarItems = datasource.tabBarItemsInCustomTabBar(self) 
customTabBarItems = [] 
tabBarButtons = [] 
let containers = createTabBarItemContainers() 
createTabBarItems(containers) 
} 

func createTabBarItems(_ containers: [CGRect]) { 

var index = 0 
for item in tabBarItems { 
    let container = containers[index] 
    let customTabBarItem = CustomTabBarItem(frame: container) 
    customTabBarItem.setup(item) 
    self.addSubview(customTabBarItem) 
    customTabBarItems.append(customTabBarItem) 
    let button = UIButton(frame: CGRect(x: 0, y: 0, width: container.width, height: container.height)) 
    button.addTarget(self, action: #selector(CustomTabBar.barItemTapped(_:)), for: UIControlEvents.touchUpInside) 
    customTabBarItem.addSubview(button) 
    tabBarButtons.append(button) 
    index += 1 
} 
} 

func barItemTapped(_ sender : UIButton) { 
let index = tabBarButtons.index(of: sender)! 
delegate.didSelectViewController(self, atIndex: index) 
} 

Answer 1

變化

class CustomTabBar: UIView { 

到：

class CustomTabBar: UITabBar { 

然後您的自定義標籤欄會像一個標籤吧！

Answer 2

嗯，我有同樣的功能，並與的UITabBarController這樣實現的。

enum TabType:Int{ 
case viewController1 = 0 
case viewController2 = 1 
case viewController3 = 2 
} 

class CustomTabbarVC: UITabBarController { 

    override func viewDidLoad() { 
     super.viewDidLoad() 
    } 

    override func didReceiveMemoryWarning() { 
     super.didReceiveMemoryWarning() 
     // Dispose of any resources that can be recreated. 
    } 

    convenience init(userType : UserType){ 
     self.init() 
     addViewControllers() 
     setupOnInit() 

     let tabBar = self.tabBar 
     tabBar.selectionIndicatorImage = UIImage().createSelectionIndicator(UIColor(red: 22/255, green: 52/255, blue: 89/255, alpha: 1.0), size: CGSize(width: tabBar.frame.width/CGFloat(tabBar.items!.count), height: tabBar.frame.height), lineWidth: 3.0) 
    } 


    func setupOnInit(){ 

     delegate = self 
     tabBar.barStyle = UIBarStyle.black 
     tabBar.isTranslucent = false 
    } 

    func addViewControllers(){ 

     // We will add 3 controllers 

     let viewController1 = viewController1(nibName: 「viewController1」, bundle: nil) 
     let viewController2 = viewController2(nibName: 「viewController2」, bundle: nil) 
     let viewController3 = viewController3(nibName: 「viewController3」, bundle: nil) 

     let viewController1Navigation = UINavigationController(rootViewController: viewController1) 
     viewController1Navigation.tabBarItem = getTabbarItem(.viewController1) 
     viewController1Navigation.tabBarItem.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0) 

     let viewController2Navigation = UINavigationController(rootViewController: viewController2) 
     viewController2Navigation.tabBarItem = getTabbarItem(.viewController2) 
     viewController2Navigation.tabBarItem.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0) 

     let viewController3Navigation = UINavigationController(rootViewController: viewController3) 
     viewController3Navigation.tabBarItem = getTabbarItem(.viewController3) 
     viewController3Navigation.tabBarItem.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0) 

     viewControllers = [viewController1Navigation,viewController2Navigation,viewController3Navigation] 

    } 


    func getTabbarItem(_ tabType:TabType)->UITabBarItem{ 

     // Fetch tab bar item and set image according to it. 

     var image = String() 
     var selectedImage = String() 

     if tabType == .viewController1{ 
      image = 「img_viewController1_tab_nonSelected」 
      selectedImage = 「img_viewController1_tab_Selected」 
     }else if tabType == .viewController2{ 
      image = 「img_viewController2_tab_nonSelected」 
      selectedImage = 「img_viewController2_tab_Selected」 
     }else if tabType == .viewController3{ 
      image = 「img_viewController3_tab_nonSelected」 
      selectedImage = 「img_viewController3_tab_Selected」 
     }else{ 
      print("Unknown tab type") 
     } 

     if let imageName:String = image,let selectedImageName:String = selectedImage{ 
      return UITabBarItem(title: nil, image: UIImage(named: imageName)?.withRenderingMode(.alwaysOriginal), selectedImage: UIImage(named: selectedImageName)?.withRenderingMode(.alwaysOriginal)) 
     }else{ 
      return UITabBarItem() 
     } 
    } 

} 

extension UIImage { 
    func createSelectionIndicator(_ color: UIColor, size: CGSize, lineWidth: CGFloat) -> UIImage { 
     UIGraphicsBeginImageContextWithOptions(size, false, 0) 
     color.setFill() 
     UIRectFill(CGRect(x: 0, y: size.height - lineWidth, width: size.width, height: lineWidth)) 
     let image = UIGraphicsGetImageFromCurrentImageContext() 
     UIGraphicsEndImageContext() 
     return image! 
    } 
} 

如何在應用程序委託實現

class AppDelegate: UIResponder, UIApplicationDelegate{ 

    var window: UIWindow? 
    var customTabbarVC: CustomTabbarVC? 

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool { 

     window = UIWindow(frame: UIScreen.main.bounds) 
     customTabbarVC = customTabbarVC() // It will invoke init methods of customtabbarvc 
     window?.rootViewController = customTabbarVC // Here your tab bar controller will setup 

     return true 
    } 

    // Other APP DELEGATE METHODS 

} 

讓我知道如果您有任何疑問..

Answer 3

對於您的自定義標籤欄按鈕更改圖像單擊該按鈕後，你需要編寫的代碼更改下面函數圖像

func barItemTapped(_ sender : UIButton) { 
} 

同樣

func barItemTapped(_ sender : UIButton) 
{ 
    if sender.tag == 1 
    { 
    tabBarButtons.setImage(UIImage(named:"FirstImage.png"), forState: .Normal) 
    } 
    else 
    { 
    tabBarButtons.setImage(UIImage(named:"SecImage.png"), forState: .Normal) 
    } 
}