摘要：最近要从零开发一个项目，之前只是在OC上搭建过TabbarViewcontroller，后来转到swift之后也只是看过，趁着现在项目前有点时间，通过一个新的Demo说一下个人认为比较简单的一种创建Tabbar的方式（包括了对Nav的封装）。
一、新建Navigationcontroller.swift和TabbarViewcontroller.swift两个类
1、Navigationcontroller.swift中(继承自UINavigationController)
- 在Navigationcontroller中写入如下代码：
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
self.navigationItem.backBarButtonItem = UIBarButtonItem.init(title: "返回", style: .plain, target: nil, action: nil)
let navbar = UINavigationBar.appearance()
navbar.setBackgroundImage(UIImage.init(named: ""), for: .default)
//按钮默认值
let tabbarItem = UITabBarItem.appearance()
let itemTextAttributesnormalDict: Dictionary< String ,AnyObject > = [NSForegroundColorAttributeName:UIColor.brown,NSFontAttributeName:UIFont.systemFont(ofSize: 20)]
let itemTextAttributesselectDict: Dictionary< String ,AnyObject > = [NSForegroundColorAttributeName:UIColor.red,NSFontAttributeName:UIFont.systemFont(ofSize: 20)]
tabbarItem.setTitleTextAttributes(itemTextAttributesnormalDict, for: .normal)
tabbarItem.setTitleTextAttributes(itemTextAttributesselectDict, for: .selected)
}
然后构造一个函数构造器
func navigationControllerWithRootViewController(Vc: UIViewController, image: UIImage, selImage: UIImage) -> UINavigationController {
let nav = UINavigationController(rootViewController: Vc)
nav.tabBarItem.image = image.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
nav.tabBarItem.selectedImage = selImage.withRenderingMode(UIImageRenderingMode.alwaysOriginal)
nav.tabBarItem?.imageInsets = UIEdgeInsetsMake(6, -2, -6, 2)
return nav;
}
到这儿就完成了Nav类里面的操作
2、TabbarViewcontroller.swift中（继承自UITabBarController，并遵守UITabBarControllerDelegate协议）
- 在TabbarViewcontroller中写入如下代码：
定义一个记录选中下标的变量
var selectIndexLast : Int?
构造tabbarVc
self.delegate = self
self.navigationItem.backBarButtonItem = UIBarButtonItem.init(title: "返回", style: .plain, target: nil, action: nil)
self.tabBar.clipsToBounds = true
self.tabBar.backgroundImage = UIImage.init(named: "se_base_tabbar_bg")//改成你图片的名字
// 新建Vc
// let home = HomeViewController()
// 调用函数构造方法
// let navhome = NavigationViewController().navigationControllerWithRootViewController(Vc: home, image: UIImage(named: "se_base_tabbar_home_gray")!, selImage: UIImage(named: "se_base_tabbar_home_light")!)
//
// let maillist = MailListViewController()
// let navmaillist = NavigationViewController().navigationControllerWithRootViewController(Vc: maillist, image: UIImage(named: "se_base_tabbar_maillist_gray")!, selImage: UIImage(named: "se_base_tabbar_maillist_light")!)
//
// let helpother = HelpOtherViewController()
// let navhelpother = NavigationViewController().navigationControllerWithRootViewController(Vc: helpother, image: UIImage(named: "se_base_tabbar_helpother_gray")!, selImage: UIImage(named: "se_base_tabbar_helpother_light")!)
//
// let my = MyViewController()
// let navmy = NavigationViewController().navigationControllerWithRootViewController(Vc: my, image: UIImage(named: "se_base_tabbar_my_gray")!, selImage: UIImage(named: "se_base_tabbar_my_light")!)
// 添加到tabbarVc中
// self.viewControllers = [navhome, navmaillist, navhelpother, navmy]
// 设置默认选中为第一个
self.tabBarController?.selectedIndex = 0
实现代理方法
override func tabBar(_ tabBar: UITabBar, didSelect item: UITabBarItem) {
selectIndexLast = self.selectedIndex
}
2、AppDelegate
- 最后在AppDelegate中将根视图设置为TabbarVc就可以了
注：所有用到的tabbarButton上的自定制样式让UI 给图的时候字+图一块切过来，这样就非常省事了。
