swift - UITabBarController View 之间的动画过渡

Question

我使用重新定义的 func tabBarController 为 tabbarcontroller 设置自定义类，但当我单击选项卡栏项目时它不会触发。完整项目在这里: https://drive.google.com/open?id=1vKmruj6yzCHv6bxw6tiRcftqN-UuAp4i

     import UIKit

    class UITabBarControllerAnimated: UITabBarController {

    override func viewDidLoad() {
        super.viewDidLoad()
        self.delegate = self as? UITabBarControllerDelegate
        print("start")
        // Do any additional setup after loading the view.
    }

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

    func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {

        if selectedViewController == nil || viewController == selectedViewController {
            print("nop")
            return false
        }

        let fromView = selectedViewController!.view
        let toView = viewController.view

        UIView.transition(from: fromView!, to: toView!, duration: 0.8, options: [.transitionCrossDissolve], completion: nil)
        print( "animation go")
        return true
    }
}

Answer 1

我检查了你的代码，问题是你的实现

self.delegate = self as? UITabBarControllerDelegate 

它无法使 UITabBarController 符合 UITabBarControllerDelegate，请进行一些更改

class UITabBarControllerAnimated: UITabBarController, UITabBarControllerDelegate {

override func viewDidLoad() {
    super.viewDidLoad()
    self.delegate = self
    print("start")
    // Do any additional setup after loading the view.
}

工作正常