Swift日常开发随笔

1、修改UISearchBar的搜索框底色

使用以下代码：
setSearchFieldBackgroundImage(CommonUseClass._sharedManager.imageFromColor(color: .white, viewSize: CGSize(width: self.bounds.size.width, height: self.bounds.size.height)), for: .normal)

//颜色创建图片
    func imageFromColor(color: UIColor, viewSize: CGSize) -> UIImage{
        let rect: CGRect = CGRect(x: , y: , width: viewSize.width, height: viewSize.height)
        UIGraphicsBeginImageContext(rect.size)
        let context: CGContext = UIGraphicsGetCurrentContext()!
        context.setFillColor(color.cgColor)
        context.fill(rect)
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsGetCurrentContext()
        return image!
    }

2、修改UITextField的placeholderLabel的默认字体颜色

inputTextField.text = ""
//备注：因为苹果公司开发过程中使用的是懒加载，所以如果不提前进行设置储值，则不会创建“_placeholderLabel”,仅仅使用以下代码不会进行更改默认字体颜色
inputTextField.setValue(colorWithHexString("0x999999"), forKeyPath: "_placeholderLabel.textColor")

3、为UICollectionView添加headerView

//备注：UICollectionView跟UITableView在设置headerView时有少许的差别。UICollection使用的是一个UICollectionReusableView来进行创建

collectionView.register(UICollectionReusableView, forSupplementaryViewOfKind: UICollectionView.elementKindSectionHeader, withReuseIdentifier: "UICollectionReusableView")

//实现代理方法
func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
        let headerView = collectionView.dequeueReusableSupplementaryView(ofKind: UICollectionView.elementKindSectionHeader, withReuseIdentifier:"UICollectionReusableView", for: indexPath)
        headerView.addSubview(contentSearchBar)
        return headerView
    }

//起初时候使用上面的代理方法不知道为何没有执行，后来设置了以下值发现竟然OK了，也不知道为啥，反正就用了。
layout.headerHeight = 

4、自定义轮播图的UIPageControl

//创建轮播视图

class NACustomBannerView: UIView, UIScrollViewDelegate {
    var timeInterval: TimeInterval = 

    private var imageUrls: [String] = [String]()
    private var imageArray: [UIImageView] = [UIImageView]()
    private var tapAction: (Int) -> Void
    private var currentIndex: Int =
    private weak var timer: Timer?

    private lazy var scrollNode: UIScrollView = {
        let node = UIScrollView()
        node.scrollsToTop = false
        node.isPagingEnabled = true
        node.bounces = false
        node.frame = self.bounds
        node.delegate = self
        node.showsHorizontalScrollIndicator = false
        node.decelerationRate = UIScrollView.DecelerationRate(rawValue: )
        node.setContentOffset(CGPoint(x: self.frame.width, y: ), animated: false)
        node.contentSize = CGSize(width: self.frame.size.width * 3.0, height: )
        return node
    }()

    lazy var pageControl: NACustomBannerPageControl = {
        let node = NACustomBannerPageControl(frame: CGRect(x: Int(UIScreen.main.bounds.width /  - ), y: Int(self.frame.height - ), width:  * self.imageUrls.count , height: ))
        node.numberOfPages = self.imageUrls.count
        return node
    }()

    // MARK: - Public
    func resetCurrentPage(_ page: Int) {
        currentIndex = page
        pageControl.currentPage = page
        resetImageView()
        startTimer()
    }

    // MARK: - Init
    init(frame: CGRect, imageUrls: [String], tapAction action: @escaping(Int) -> Void) {
        self.imageUrls = imageUrls
        self.tapAction = action
        super.init(frame: frame)

        addImageView()
        addSubview(scrollNode)
        addSubview(pageControl)
        startTimer()
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    // MARK: - UIScrollViewDelegate
    func scrollViewDidScroll(_ scrollView: UIScrollView) {
        let contentOffsetX = scrollView.contentOffset.x
        // 设置图片信息
        if contentOffsetX ==  * scrollView.frame.width {// 左滑
            currentIndex = getActualCurrentPage(calculatedPage: currentIndex + )
            resetImageView()
        } else if (contentOffsetX == ) {// 右滑
            currentIndex = getActualCurrentPage(calculatedPage: currentIndex - )
            resetImageView()
        }

        // 设置 pageControl
        if contentOffsetX < scrollView.frame.width && contentOffsetX >  {
            if contentOffsetX <= scrollView.frame.width * 0.5 {
                pageControl.currentPage = getActualCurrentPage(calculatedPage: currentIndex - )
            } else if contentOffsetX > scrollView.frame.width * 0.5 {
                pageControl.currentPage = getActualCurrentPage(calculatedPage: currentIndex)
            }
        } else if contentOffsetX > scrollView.frame.width && contentOffsetX < scrollView.frame.width *  {
            if contentOffsetX >= scrollView.frame.width * 1.5 {
                pageControl.currentPage = getActualCurrentPage(calculatedPage: currentIndex + )
            } else if contentOffsetX < scrollView.frame.width * 1.5 {
                pageControl.currentPage = currentIndex
            }
        }

    }

    func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
        scrollView.setContentOffset(CGPoint(x: self.frame.width, y: ), animated: true)
        startTimer()
    }

    func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
        timer?.invalidate()
        timer = nil
    }

    // MARK: - Action
    @objc fileprivate func cycleViewDidClick(gesture: UITapGestureRecognizer) {
        print("点击了第\(currentIndex)张图")
        let imageView = UIImageView(frame: CGRect(x: , y: , width: frame.width, height: frame.height))
        imageView.kf.setImage(with: URL(string: imageUrls[currentIndex]))
        tapAction(currentIndex)
    }

    @objc fileprivate func autoScroll() {
        if imageUrls.count <  {
            return
        }
        scrollNode.setContentOffset(CGPoint(x: self.frame.width * , y: ), animated: true)
    }

    func startTimer() {
        guard imageUrls.count >  else { return }

        if let myTimer = timer {
            myTimer.invalidate()
            timer = nil
        }
        timer = Timer.scheduledTimer(timeInterval: self.timeInterval, target: self, selector: #selector(autoScroll), userInfo: nil, repeats: true)
        RunLoop.current.add(timer!, forMode: RunLoop.Mode.common)
    }

    func invalidateTimer() {
        timer?.invalidate()
        timer = nil
    }

    fileprivate func addImageView() {
        var x: CGFloat =
        var pageIndex: NSInteger = self.imageUrls.count -
        for index in ..< {
            let imgNode = UIImageView()
            x = CGFloat(index) * frame.width
            imgNode.frame = CGRect(x: x, y: , width: frame.width, height: frame.height)
            imgNode.kf.setImage(with: URL(string: imageUrls.count ==  ? "" : (imageUrls[pageIndex])))
            imgNode.contentMode = .scaleAspectFill
            imgNode.clipsToBounds = true

            let gesture = UITapGestureRecognizer(target: self, action: #selector(cycleViewDidClick(gesture:)))
            imgNode.addGestureRecognizer(gesture)
            imgNode.isUserInteractionEnabled = true
            imageArray.append(imgNode)
            scrollNode.addSubview(imgNode)

            if imageUrls.count ==  {
                pageIndex =
                scrollNode.isScrollEnabled = false
            } else {
                pageIndex = index ==  ?  :
            }
        }

    }

    fileprivate func resetImageView(){

        let preIndex: NSInteger = getActualCurrentPage(calculatedPage: currentIndex - )
        let nextIndex: NSInteger = getActualCurrentPage(calculatedPage: currentIndex + )

        if imageUrls.count ==  {
            return
        }

        imageArray[].kf.setImage(with: URL(string: imageUrls[preIndex]))
        imageArray[].kf.setImage(with: URL(string: imageUrls[currentIndex]))
        imageArray[].kf.setImage(with: URL(string: imageUrls[nextIndex]))

        scrollNode.contentOffset = CGPoint(x: self.frame.width, y: )
    }

    fileprivate func getActualCurrentPage(calculatedPage page: NSInteger) -> NSInteger {
        if page == imageUrls.count {
            return
        } else if page == - {
            return imageUrls.count -
        } else {
            return page
        }
    }
}

自定义轮播视图

import UIKit

class NACustomBannerPageControl: UIView {
    let pageControlDiameter: Float =
    var currentPage: NSInteger =  {
        didSet {
            if oldValue == currentPage {
                return
            }

            if currentPage < oldValue {// 向右拉伸
                UIView.animate(withDuration: 0.3, animations: {
                    for dot in self.subviews {
                        var dotFrame = dot.frame
                        if dot.tag == self.currentPage {
                            dotFrame.size.width = CGFloat(self.pageControlDiameter * 2.0)
                            dot.backgroundColor = colorWithHexString("0xfdd000")
                            dot.frame = dotFrame

                        } else if dot.tag <= oldValue && dot.tag > self.currentPage {
                            dotFrame.origin.x += CGFloat(self.pageControlDiameter)
                            dotFrame.size.width = CGFloat(self.pageControlDiameter)
                            dot.backgroundColor = .white
                            dot.frame = dotFrame
                        }
                    }
                })

            } else {
                UIView.animate(withDuration: 0.3, animations: {
                    for dot in self.subviews {
                        var dotFrame = dot.frame
                        if dot.tag == self.currentPage {
                            dotFrame.size.width = CGFloat(self.pageControlDiameter * 2.0)
                            dotFrame.origin.x -= CGFloat(self.pageControlDiameter)
                            dot.backgroundColor = colorWithHexString("0xfdd000")
                            dot.frame = dotFrame

                        } else if dot.tag > oldValue && dot.tag < self.currentPage {
                            dotFrame.origin.x -= CGFloat(self.pageControlDiameter)
                            dot.frame = dotFrame

                        } else if dot.tag == oldValue {
                            dotFrame.size.width = CGFloat(self.pageControlDiameter)
                            dot.backgroundColor = .white
                            dot.frame = dotFrame
                        }
                    }
                })

            }

        }
    }
    var numberOfPages: NSInteger =  {
        didSet {
            if self.numberOfPages ==  {
                return
            }
            if self.subviews.count >  {
                for view in self.subviews {
                    view.removeFromSuperview()
                }
            }

            var dotX: Float = ;
            var dotW: Float = pageControlDiameter;
            var bgColor: UIColor
            for i in ..<numberOfPages {
                if i <= currentPage {
                    dotX = pageControlDiameter * 2.0 * Float(i)
                } else {
                    dotX = pageControlDiameter *  * Float(i) + pageControlDiameter
                }

                if i == currentPage {
                    dotW = pageControlDiameter * ;
                    bgColor = colorWithHexString("0xfdd000")
                } else {
                    dotW = pageControlDiameter;
                    bgColor = .white
                }

                let temp = UIView()
                temp.frame = CGRect(x: CGFloat(dotX), y: CGFloat(), width: CGFloat(dotW), height: CGFloat(pageControlDiameter))
                temp.layer.cornerRadius = CGFloat(pageControlDiameter * 0.5)
                temp.layer.masksToBounds = true
                temp.backgroundColor = bgColor
                temp.tag = i
                addSubview(temp)
            }

        }
    }

}

自定义UIPageControl样式

func setUpTurnsChangeItem() -> Void {
        let x = (SCREEN_WIDTH - )/
        let frame = CGRect(x: x, y: CGFloat(), width: , height: )
        let urls = ["http://p.lrlz.com/data/upload/mobile/special/s252/s252_05471521705899113.png",              "http://p.lrlz.com/data/upload/mobile/special/s303/s303_05442007678060723.png",                  "http://p.lrlz.com/data/upload/mobile/special/s303/s303_05442007587372591.png",                    "http://p.lrlz.com/data/upload/mobile/special/s303/s303_05442007388249407.png",                    "http://p.lrlz.com/data/upload/mobile/special/s303/s303_05442007470310935.png"]
        cycleScrollView = NACustomBannerView(frame: frame, imageUrls: urls) { (index) in
            print("当前第\(index)张")
        }
        cycleScrollView.layer.masksToBounds = true
        cycleScrollView.layer.cornerRadius = 5.0
        container.addSubview(cycleScrollView)

    }

使用方法

效果图如下：

5、自定义下拉列表

import UIKit

class NACustomDropListView: UIView,UITableViewDelegate,UITableViewDataSource{
    fileprivate var cellid = "cellid"
    lazy  var titleArray = [String]()
    lazy  var tableArray = [[String]]()
    var screenWidth = SCREEN_WIDTH
    var screenHeight = SCREEN_HEIGHT
    var maskViewSS:UIView?
    var selectClosure:((_ tag:Int,_ row:Int)->Void)?
    init(frame: CGRect,tableArr:[[String]],selectClosure : @escaping (_ tag:Int,_ row:Int)->Void) {
        super.init(frame: frame)
        self.titleArray = tableArr.map({ (arr) -> String in
            return arr[]
        })
        self.tableArray = tableArr
        self.selectClosure = selectClosure
        self.backgroundColor = UIColor.white
        self.setTitleButton()
        setMaskView()
        setTableView()
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    func setMaskView(){
        let height = Int(Int(SCREEN_HEIGHT) -  - Int(CommonUseClass._sharedManager.navigationBarHeight()))
        maskViewSS = UIView.init(frame: CGRect(x: , y: , width: Int(screenWidth), height:height))
        maskViewSS?.backgroundColor = newColorWithAlpha(, , , 0.3)
        let tap = UITapGestureRecognizer.init(target: self, action: #selector(tapAction))

        maskViewSS?.alpha =
        maskViewSS?.addGestureRecognizer(tap)

    }
    @objc func tapAction(){
        for i in ..<self.tableArray.count{
            let tableView = self.viewWithTag(+i) as! UITableView
            let drop = self.viewWithTag(+i) as! NACustomDropListTitleView

            if tableView.frame.height>{
                drop.isSelected = false
                UIView.animate(withDuration: 0.2, animations: {
                    tableView.frame = CGRect.init(x: , y: , width: UIScreen.main.bounds.width, height: )
                    self.maskViewSS?.alpha =
                }, completion: { (idCom) in
                    self.maskViewSS?.removeFromSuperview()
                })

            }
        }
    }
    func setTitleButton(){
        let totalArry:Array<Array<String>>  = self.tableArray
        let width:CGFloat = screenWidth / CGFloat(titleArray.count)

        for i in ..<self.titleArray.count{
            let view = NACustomDropListTitleView.init(frame: CGRect.init(x: CGFloat(i)*width, y: , width: width, height: ), title: titleArray[i])
            view.tag = +i
            view.gesClosure = { (select)->Void in
                self.insertSubview(self.maskViewSS!, at: )
                UIView.animate(withDuration: 0.2, animations: {
                    self.maskViewSS?.alpha =
                })
                if select {

                    for n in ..<self.titleArray.count {
                        let drop = self.viewWithTag(+n) as! NACustomDropListTitleView
                        let tableView = self.viewWithTag(+n) as! UITableView
                        if i == n {
                            drop.isSelected = true

                        }else{
                            drop.isSelected = false
                        }
                        let arr = totalArry[n] as [String]
//                        tableView.reloadData()

                        if i == n {
                            UIView.animate(withDuration: 0.2, animations: {
                                let height2 = Int(arr.count) *  +
                                let height1 = Int(Int(SCREEN_HEIGHT) -  - Int(CommonUseClass._sharedManager.navigationBarHeight()))

                                tableView.frame = CGRect(x: , y: , width: Int(self.screenWidth), height: height2 > height1 ? height1 : height2)
                            })

                        }else{
                            UIView.animate(withDuration: 0.2, animations: {
                                tableView.frame = CGRect.init(x: , y: , width: self.screenWidth, height: )
                            })
                        }
                    }
                }else{

                    let tableView = self.viewWithTag(+i) as! UITableView

                    UIView.animate(withDuration: 0.2, animations: {
                        tableView.frame = CGRect.init(x: , y: , width: self.screenWidth, height: )
                        self.maskViewSS?.alpha =
                    }, completion: { (idCom) in
                        self.maskViewSS?.removeFromSuperview()
                    })

                }

            }
            self.addSubview(view)

        }
    }
    func setTableView(){
        let totalArry:Array<Array<String>>  = self.tableArray

        for i in ..<totalArry.count{

            let tableView = UITableView.init(frame: CGRect.init(x: , y: , width: screenWidth, height: ), style: .plain)

            tableView.delegate = self
            tableView.dataSource = self
            tableView.tag = +i
            tableView.backgroundColor = UIColor.white
            tableView.register(UITableViewCell.self, forCellReuseIdentifier: cellid)
            tableView.rowHeight =
            tableView.isScrollEnabled = false
            tableView.separatorStyle = .none
            self.addSubview(tableView)

        }
    }
    override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
        var view = super.hitTest(point, with: event)
        if view == nil {
            for subView in self.subviews {
                let tp = subView.convert(point, from: self)
                if subView.bounds.contains(tp) {
                    view = subView
                }
            }
        }
        return view
    }

}
extension NACustomDropListView{
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        let drop = self.viewWithTag(tableView.tag-+) as! NACustomDropListTitleView
        let cell = tableView.cellForRow(at: indexPath)

        drop.title  = cell?.textLabel?.text
        if self.selectClosure != nil {
            self.selectClosure!(tableView.tag,indexPath.row)
        }

        drop.isSelected = false
        UIView.animate(withDuration: 0.2, animations: {
            tableView.frame = CGRect.init(x: , y: , width: self.screenWidth, height: )
            self.maskViewSS?.alpha =
        }, completion: { (idCom) in
            self.maskViewSS?.removeFromSuperview()
        })

    }
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        let drop = self.viewWithTag(tableView.tag-+) as! NACustomDropListTitleView
        if drop.isSelected == nil {
            return
        }else{
            return  drop.isSelected! ? self.tableArray[tableView.tag-].count :
        }

    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: cellid, for: indexPath) as UITableViewCell
        cell.textLabel?.font = UIFont.systemFont(ofSize: )
        cell.textLabel?.text = tableArray[tableView.tag - ][indexPath.row]

        return cell
    }
}

自定义下拉列表View

import UIKit
import SnapKit
typealias GesClosure = (_ selected:Bool)->Void
class NACustomDropListTitleView: UIView {
    var label:UILabel!
    var downIcon:UIImageView!
    var topIcon:UIImageView!

    var ly_width:CGFloat?
    var title:String?{
        didSet{
            self.ly_width = CommonUseClass._sharedManager.getStringRect(text: self.title!,font: UIFont.systemFont(ofSize: )).width +
            label.text = self.title
            if title == "价格"{
                centerLayoutConstraints()
            }else{
                commponLayoutConstraints()
            }

        }
    }
    var _isSelect:Bool = false
    var gesClosure:GesClosure?
    var isSelected:Bool?{
        didSet{
            self._isSelect = isSelected!
            if isSelected! {
                self.downIcon.image = UIImage.init(named: "ic_down_y")
                self.label.textColor = colorWithHexString("0xfdd000")
            }else{
                self.downIcon.image = UIImage.init(named: "ic_down_f")
                self.label.textColor = colorWithHexString("0x000000")
            }

        }
    }
    init(frame: CGRect,title:String) {
        super.init(frame: frame)
        self.title = title
        self.ly_width = CommonUseClass._sharedManager.getStringRect(text: self.title!,font: UIFont.systemFont(ofSize: )).width +
        setUI(title: title)
        if title == "价格" {
            centerLayoutConstraints()
        }else{
            commponLayoutConstraints()
        }

        setGes()
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    func setGes(){
        let ges = UITapGestureRecognizer.init(target: self, action: #selector(tapAction))

        self.addGestureRecognizer(ges)
    }

    @objc func tapAction(){
        self._isSelect = !self._isSelect
        self.isSelected = self._isSelect
        if (self.gesClosure != nil){
            self.gesClosure!(self.isSelected!)
        }

    }

    func setUI(title:String){

        label = UILabel()
        addSubview(label)
        label.font = UIFont.systemFont(ofSize: )
        label.textColor = colorWithHexString("0x000000")
        label.text = self.title

        downIcon = UIImageView.init()
        downIcon.image = UIImage.init(named:"ic_down_f")
        addSubview(downIcon)

        topIcon = UIImageView.init()
        topIcon.image = UIImage.init(named:"ic_down_f")
        addSubview(topIcon)
        UIView.animate(withDuration: 0.2, animations: {
            self.topIcon.transform = CGAffineTransform.init(rotationAngle: CGFloat(Double.pi))

        })
    }

    func labelConstraints() -> Void {
        label.snp.removeConstraints()
        downIcon.snp.removeConstraints()
        label.snp.makeConstraints { (make) in
            make.centerY.equalTo(self)
            make.centerX.equalTo(self)
            make.height.equalTo()
            make.width.equalTo(ly_width!)
        }
    }
    func commponLayoutConstraints(){
        labelConstraints()
        downIcon.snp.makeConstraints { (make) in
            make.left.equalTo(label.snp.right).offset()
            make.centerY.equalTo(label)
            make.width.equalTo()
            make.height.equalTo()

        }
    }

    func centerLayoutConstraints() -> Void {
        labelConstraints()

        topIcon.snp.makeConstraints { (make) in
            make.left.equalTo(label.snp.right).offset()
            make.top.equalTo(label).offset()
            make.width.equalTo()
            make.height.equalTo()
        }

        downIcon.snp.makeConstraints { (make) in
            make.left.equalTo(label.snp.right).offset()
            make.bottom.equalTo(label).offset(-)
            make.width.equalTo()
            make.height.equalTo()

        }

    }

}

自定义下拉列表titleView

lazy var dropListView : NACustomDropListView = {
        let dropListView = NACustomDropListView.init(frame: CGRect(x: CGFloat(), y: , width: SCREEN_WIDTH, height: CGFloat()), tableArr: [moneyArray,limitArray,sortArray], selectClosure: { (tag, row) in
            print(tag-,row)
        })
        return dropListView
    }()

view.addSubview(dropListView)

使用方法

运行效果：

提示：之所以为空白，是因为我把下拉列表中的tableView.reloadData()这行代码屏蔽掉了，加入的数组没有刷新。

6、隐藏navigationBar和tabbar的黑色分割线

//隐藏navigationBar下面的分割线
self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .any, barMetrics: .default)
self.navigationController?.navigationBar.shadowImage = UIImage()

//隐藏tabbar上面的分割线
self.tabBarController?.tabBar.shadowImage = UIImage.init()
self.tabBarController?.tabBar.backgroundImage = UIImage.init()

7、获取导航栏+状态栏的高度

func navigationBarHeight() -> Float {
        var navigationBarH: Float =
        if IS_IPHONE_X.boolValue {
            navigationBarH +=
        }else{
            navigationBarH +=
        }
        return navigationBarH
    }

8、判断字符串是否为空

func StringIsEmpty(value: AnyObject?) -> Bool {
        if (nil == value) {
            return true
        }else{
            if let myValue  = value as? String{
                return myValue == "" || myValue == "(null)" ||  == myValue.count
            }else{
                return true
            }
        }
    }

9、判断是否是整数

func isPurnInt(string: String) -> Bool {
        let scan: Scanner = Scanner(string: string)
        var val:Int =
        return scan.scanInt(&val) && scan.isAtEnd
    }

10、添加阴影效果

func setShadow(view:UIView,sColor:UIColor,offset:CGSize,
                   opacity:Float,radius:CGFloat) {
        view.layer.shadowColor = sColor.cgColor
        view.layer.shadowOpacity = opacity
        view.layer.shadowRadius = radius
        view.layer.shadowOffset = offset
    }

使用实例：setShadow(view: groundView, sColor: .black, offset: CGSize(width: 1, height: 1), opacity:0.15, radius: 5)

11、颜色创建图片

func imageFromColor(color: UIColor, viewSize: CGSize) -> UIImage{
        let rect: CGRect = CGRect(x: , y: , width: viewSize.width, height: viewSize.height)
        UIGraphicsBeginImageContext(rect.size)
        let context: CGContext = UIGraphicsGetCurrentContext()!
        context.setFillColor(color.cgColor)
        context.fill(rect)
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsGetCurrentContext()
        return image!
    }

12、获取字符串的宽度、高度

func getStringRect(text:String, font:UIFont) -> CGRect {
        let strText: NSString = NSString( string: text )
        let size:CGSize = CGSize(width: , height: )
        let options:NSStringDrawingOptions = NSStringDrawingOptions.usesLineFragmentOrigin
        let boundRect = strText.boundingRect(with: size, options: options, attributes: [NSAttributedString.Key.font: font], context: nil)
        return boundRect
    }

所用代码：均是swift 4.2下运行