//

//  DSegmentedControl.swift

//  IOS学习之自定义UISegmentedControl

//

//  Created by ding_qili on 16/9/12.

//  Copyright © 2016年 ding_qili. All rights reserved.

//

import UIKit

@IBDesignable class DSegmentedControl: UIControl {

    /*

    // Only override drawRect: if you perform custom drawing.

    // An empty implementation adversely affects performance during animation.

    override func drawRect(rect: CGRect) {

        // Drawing code

    }

    */

    var titleColor:UIColor = UIColor.gray //选择状态

    var titleColorDisable:UIColor = UIColor.darkGray //未选中状态

    let slide =  CALayer() //滑块

    @IBInspectable var titles:[String]{ //标题

        didSet{

            guard titles.count > 0 else {

                return

            }

            for title in 0..<titles.count {

                let label =  UIButton();

                label.setTitle(titles[title], for: UIControlState());

                label.setTitleColor(titleColor, for: UIControlState.disabled)

                label.setTitleColor(titleColorDisable, for: UIControlState())

                label.addTarget(self, action: #selector(changeValue), for: UIControlEvents.touchUpInside);

                self.addSubview(label);

            }

            setNeedsLayout()

        }

    }

    override func tintColorDidChange() {

        super.tintColorDidChange()

    }

    var selecteIndex:Int = 0 {

        didSet{

            refrushSubView()

        }

    }

    override init(frame: CGRect) {

        titles = []

        super.init(frame: frame)

        finishInit()

    }

    requi 大专栏  自定义一个简单的SegmentedControlred init?(coder aDecoder: NSCoder) {

        titles = []

        super.init(coder: aDecoder)

        finishInit()

    }

    func changeValue(_ sender:UIView){

        if let index =  self.subviews.index(of: sender){

            selecteIndex = index;

            self.sendActions(for: UIControlEvents.valueChanged)

        }

    }

    func finishInit(){

        titleColor = self.tintColor

        slide.frame = CGRect(x: 0, y: 0, width: self.frame.width/2, height: 1)

        slide.backgroundColor = titleColor.cgColor

        self.layer.addSublayer(slide)

        self.backgroundColor = UIColor.clear

    }

    override func layoutSubviews() {

        super.layoutSubviews()

        refrushSubView()

    }

    func refrushSubView(){

        for item in self.subviews.enumerated() {

            item.element.frame = CGRect(x: self.frame.width/CGFloat(titles.count) * CGFloat(item.offset), y: 0, width: self.frame.width/CGFloat(titles.count), height: self.frame.height)

            if selecteIndex ==  item.offset{

                var center =  item.element.center;

                center.y = self.frame.height;

                slide.position = center;

            }

            if let uIControl = item.element as? UIControl {

                uIControl.isEnabled = (selecteIndex !=  item.offset);

            }

        }

    }

}

1. 选择继承UIControl,是想要通过UIControlEvents.valueChanged的方式来通知调用者切换状态

2. 默认是用了TintColor作为主色调来使用

3. `segment.titles = ["简介","评论"]` 就可以使用了

4. `segment.addTarget(self, action: #selector(segmentValueChange), for: UIControlEvents.valueChanged)` 回调选择切换

5. 代码比较简单，用于简单的学习