问题描述
使用下面的代码,我可以在导航栏中获取标题图像,但 titlepressed
方法没有调用.. 如果我点击标题,我将无法转到 HomeVC.. 请帮忙.. 我在哪里错了
func setUpNavigationBar(){
let logoImageView = UIImageView.init(image: #imageLiteral(resourceName: "pic-logo"))
logoImageView.tintColor = .darkGray
logoImageView.frame = CGRect(x:0.0,y:0.0,width:100,height:25.0)
logoImageView.contentMode = .scaleAspectFit
logoImageView.widthAnchor.constraint(equalToConstant: 200).isActive = true
logoImageView.heightAnchor.constraint(equalToConstant: 50).isActive = true
self.navigationItem.titleView?.isUserInteractionEnabled = true
let titleTap = UITapGestureRecognizer(target: self,action: #selector(titlepressed))
self.navigationItem.titleView?.addGestureRecognizer(titleTap)
self.navigationItem.titleView = logoImageView
}
@objc func titlepressed(){
print("title clicked...")
let vc = StoryBoard.main.instantiateViewController(identifier: "HomeVC") as! HomeVC
self.navigationController?.pushViewController(vc,animated: true)
}
解决方法
self.navigationItem.titleView?.addGestureRecognizer(titleTap)
self.navigationItem.titleView = logoImageView
你添加一个手势识别器,如果标题视图不是 nil,然后在下一行你立即将标题视图更改为完全不同的东西,它不会有一个手势识别器。
self.navigationItem.titleView = logoImageView
logoImageView.addGestureRecognizer(titleTap)
这一行:
self.navigationItem.titleView?.isUserInteractionEnabled = true
也是有问题的,因为:此时 titleView 可能是 nil,所以这一行什么都不做,无论如何你稍后更改标题视图。