iOS 10 barTintColor动画

Question

我注意到ios 10中条形色调动画的方式发生了变化.我创建了一个概述更改的示例项目:Github:ios10BarTintDemo

基本上在ios 9上,barTintColor可以平滑地使用 [UIViewControllerTransitionCoordinator animateAlongsideTransition]

但是在ios 10上,动画不太平滑,当弹出一个视图控制器根本没有动画时,我尝试[self.navigationController.navigationBar layoutIfNeeded]在一些类似的答案中添加,但这在推/控制器时似乎没有任何效果.

Answer 1

UPDATE

我已经在iOS 10.3中测试过,我认为这个问题已得到修复.而且transitionCordinator不再需要了.我觉得动画很流畅.请检查我在github上的项目或查看此代码:

class ViewControllerA: UIViewController {

    override func loadView() {
        super.loadView()
        title = "A"
        view.backgroundColor = .white
        navigationItem.rightBarButtonItem = UIBarButtonItem(title: "NEXT", style: .plain, target: self, action: #selector(self.showController))
    }

    override func viewWillAppear(_ animated: Bool) {
        setColors()
        super.viewWillAppear(animated)
    }

    func showController() {
        navigationController?.pushViewController(ViewControllerB(), animated: true)
    }

    private func setColors() {
        navigationController?.navigationBar.tintColor = .black
        navigationController?.navigationBar.barTintColor = .red
        navigationController?.navigationBar.isTranslucent = false
    }
}




class ViewControllerB: UIViewController {

    override func loadView() {
        super.loadView()
        title = "B"
        view.backgroundColor = .white
    }

    override func viewWillAppear(_ animated: Bool) {
        setColors()
        super.viewWillAppear(animated)
    }

    override func willMove(toParentViewController parent: UIViewController?) {
        if parent == nil {
            navigationController?.navigationBar.barTintColor = .red
        }
        super.willMove(toParentViewController: parent)
    }


    private func setColors() {
        navigationController?.navigationBar.tintColor = .black
        navigationController?.navigationBar.barTintColor = .blue
        navigationController?.navigationBar.isTranslucent = false
    }
}

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为了实现这种动画,你应该使用的UIViewControllerTransitionCoordinator是苹果的文件说,这是:

采用UIViewControllerTransitionCoordinator协议的对象为与视图控制器转换关联的动画提供支持.(...)

所以每个人UIViewController都拥有transitionController.要得到这个,你应该打电话给UIViewControllerClass:

self.transitionCoordinator()

来自文档:

返回活动的转换协调器对象.

因此,要获得您想要的结果,您应该animateAlongsideTransition在viewController transitionCoordinatior中实现方法.单击backButton并向后滑动即可使用动画.

示例:

第一控制员:

class ViewControllerA: UIViewController {

    override func loadView() {
        super.loadView()
        title = "A"
        view.backgroundColor = .white
        navigationItem.rightBarButtonItem = UIBarButtonItem(title: "NEXT", style: .plain, target: self, action: #selector(self.showController))
        setColors()
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        animate()
    }

    func showController() {
        navigationController?.pushViewController(ViewControllerB(), animated: true)
    }

    private func animate() {
        guard let coordinator = self.transitionCoordinator else {
            return
        }

        coordinator.animate(alongsideTransition: {
            [weak self] context in
            self?.setColors()
        }, completion: nil)
    }

    private func setColors() {
        navigationController?.navigationBar.tintColor = .black
        navigationController?.navigationBar.barTintColor = .red
    }
}

第二控制器:

class ViewControllerB : UIViewController {

    override func loadView() {
        super.loadView()
        title = "B"
        view.backgroundColor = .white
        setColors()
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        animate()
    }

    override func willMove(toParentViewController parent: UIViewController?) { // tricky part in iOS 10
        navigationController?.navigationBar.barTintColor = .red //previous color
        super.willMove(toParentViewController: parent)
    }

    override func viewDidAppear(_ animated: Bool) {
        navigationController?.navigationBar.barTintColor = .blue
    }

    private func animate() {
        guard let coordinator = self.transitionCoordinator else {
            return
        }
        coordinator.animate(alongsideTransition: {
            [weak self] context in
            self?.setColors()
        }, completion: nil)
    }

    private func setColors(){
        navigationController?.navigationBar.tintColor = .black
        navigationController?.navigationBar.barTintColor = .blue
    }

}

更新iOS 10

在iOS 10中,棘手的部分是willMoveTo(parentViewController parent: UIViewController?)在第二个 ViewController中添加.并将navigationBar设置tintColor为上一个控制器的颜色值.另外,在第二个 ViewControler 中的viewDidAppear方法中,设置第二个 viewController 的颜色.navigationBar.tintColor

在github上查看我的示例项目

Answer 2

您可以通过添加类似于此的内容来修复此弹出问题,在viewWillDisappear中运行它将因iOS10中的某些原因而无法正常工作

override func willMove(toParentViewController parent: UIViewController?) {
    self.navigationController?.navigationBar.barTintColor = UIColor.red
    super.willMove(toParentViewController: parent)
}