动态加载视图

步骤
  1. 获取JSON文件路径
  2. 根据路径创建NSData对象
  3. 根据NSData对象对JSON进行序列化,得到一个数组
  4. 遍历数组,提取出视图名,标题,图片名,根据这三项创建视图,并用UINavigationViewController包裹起来,将navi添加到tabBarViewController中.
MainVCSettings.json文件
[
 {
    "vcName": "HomeTableViewController",
    "title": "首页",
    "imageName": "tabbar_home"
 },
 {
     "vcName": "MessageTableViewController",
     "title": "消息",
     "imageName": "tabbar_message_center"
 },
 {
 "vcName": "NullViewController",
 "title": "",
 "imageName": ""
 },
 {
     "vcName": "DiscoverTableViewController",
     "title": "广场",
     "imageName": "tabbar_discover"
 },
 {
     "vcName": "ProfileTableViewController",
     "title": "我",
     "imageName": "tabbar_profile"
 }
 ]
具体实现代码
//
//  MainViewController.swift
//  weibo
//
//  Created by Adrift on 16/6/5.
//  Copyright © 2016年 Adrift. All rights reserved.
//

import UIKit

class MainViewController: UITabBarController {

    //MARK: - 生命周期
    override func viewDidLoad() {
        super.viewDidLoad()
        //设置当前控制器对应的tabBar的颜色,iOS7之前如果设置了tintClor只有文字会变,而图片不会变
        tabBar.tintColor = UIColor.orangeColor()
        addChildViewControllers()
    }

    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(true)
        tabBar.addSubview(composeBtn)
        //计算宽度
        let width = UIScreen.mainScreen().bounds.width / CGFloat(viewControllers!.count)
        //创建 frame
        let rect = CGRect(x: 0, y: 0, width: width, height: tabBar.bounds.height)
        //设置 frame 跟 偏移量
        composeBtn.frame = CGRectOffset(rect, width * 2, 0)

    }

    //MARK: - 方法
    /**
     添加所有子控制器
     */
    func addChildViewControllers() {
        //获取json文件路径
        let path = NSBundle.mainBundle().pathForResource("MainVCSettings", ofType: "json")
        //通过文件路径创建NSData
        if let tempPath = path {
            let jsonData = NSData(contentsOfFile: tempPath)
            do {
                //序列化
                let dictArr = try NSJSONSerialization.JSONObjectWithData(jsonData!, options: NSJSONReadingOptions.MutableContainers) as! [[String: String]]
                //遍历数组,并创建视图控制器
                for dict in dictArr {
                    addChildViewController(dict["vcName"]!, title: dict["title"]!, imageName: dict["imageName"]!)
                }
            }catch{
                print("crash")
                //并添加到TabBarViewController
                addChildViewController("HomeTableViewController", title: "首页", imageName: "tabbar_home")
                addChildViewController("MessageTableViewController", title: "消息", imageName: "tabbar_message_center")
                addChildViewController("NullViewController", title: "", imageName: "")
                addChildViewController("DiscoverTableViewController", title: "发现", imageName: "tabbar_discover")
                addChildViewController("ProfileTableViewController", title: "我的", imageName: "tabbar_profile")
            }
        }
    }

    /**
     将navigationViewController 添加到 TabBarViewController

     - parameter childController: 子控制图
     - parameter title:           标题
     - parameter imageName:       非高亮图片名称
     */
    private func addChildViewController(childControllerName: String, title: String, imageName: String) {
        //获取命名空间
        let speaceName = NSBundle.mainBundle().infoDictionary!["CFBundleExecutable"] as! String

        //通过字符串转换为类
        let cls:AnyClass? = NSClassFromString(speaceName + "." + childControllerName)

        //通过类创建对象
        let vcCls = cls as! UIViewController.Type
        let vc = vcCls.init()

//        设置首页
        vc.tabBarItem.image = UIImage(named: imageName)
        vc.tabBarItem.selectedImage = UIImage(named: imageName + "_highlighted")
        vc.title = title
        //2.给首页包装一个导航器
        let navi = UINavigationController()
        navi.addChildViewController(vc)
        //3.将导航控制器添加到当前控制器
        addChildViewController(navi)
    }

    func composeBtnClick() {
        print("被点击...")
    }

    //MARK: - 懒加载
    private lazy var composeBtn:UIButton = {

        let button = UIButton()

        //设置button图片
        button.setImage(UIImage(named: "tabbar_compose_icon_add"), forState: UIControlState.Normal)
        button.setImage(UIImage(named: "tabbar_compose_icon_add_highlighted"), forState: UIControlState.Highlighted)

        //设置button背景图片
        button.setBackgroundImage(UIImage(named: "tabbar_compose_button"), forState: UIControlState.Normal)
        button.setBackgroundImage(UIImage(named: "tabbar_compose_button_highlighted"), forState: UIControlState.Highlighted)

        //添加监听事件
        button.addTarget(self, action: #selector(MainViewController.composeBtnClick), forControlEvents: UIControlEvents.TouchUpInside)

        return button
    }()
}

--EOF--