二维码扫面当下很流行,也带来了很多的便利。我也不是在吹捧,你也许你也发现,几乎凡是个APP,都有扫描二维码的功能。现在网上的资料很多,我也是闲的蛋疼,在做一个美团的高仿项目,涉及到二维码的扫描功能,iOS7之前,开发者进行扫码编程时,一般会借助第三方库。常用的是ZBarSDKa和ZXingObjC,iOS7之后,系统的AVMetadataObject类中,为我们提供了解析二维码的接口。经过测试,使用原生API扫描和处理的效率非常高,远远高于第三方库。我查了很多的资料,网上关于用系统原生类来实现二维码扫描的资料还是很多的,但都不是很全。所以我把一套功能的实现分享出来,希望你们喜欢。(刚来简书,文章的排版还不是很熟,蛋疼!,还有就是打开项目时,要是不是真机仿真,要先注释掉beginScanning()方法,要不程序会崩溃)
这里是Swift版的,如果你想使用OC来实现,翻译过去我相信也不是难事。
OC也可以参考:http://yimouleng.com/2016/01/13/ios-QRCode/
这里包含:
- 1、窗口的搭建
- 2、二维码的扫描
- 3、从相册中读取二维码
- 4、生成二维码
- 5、长按识别二维码
其中二维码的扫描主要是用到AVFoundation
这个框架中的AVCaptureSession
,读取二维码和识别二维码是同个原理,只是处理方式不同,主要用到的是CIDetector
类,而生成二维码要用到CoreImage
框架中的CIFilter
滤镜类,值得一提的是CoreImage
非常强大,这是iOS中关于图片处理的几乎所有内容集合,即图片的处理几乎都在CoreImage
中,CIFilter
也非常值得一究,mac上应该在CoreQuartz
中。CoreImage
和CIFilter
的内容很多,我可能会在另外的文章中去分享。(我并不是大神,不敢吹牛逼说给大家讲解,只是分享和大家相互学习)
详情看看我的源码:
美团的高仿项目 更多模块中的“扫一扫”
1、窗口的搭建
这是UI的东西,很简单,想怎么弄就怎么弄,只要你happy就ok,这是我的代码:
1.1、设置导航条:setupNavView(),editItemAction()中因为在iOS9+平台,所以用UIAlertController来列出多个ActionSheet功能
func setupNavView() {
self.navigationController?.navigationBar.barTintColor = UIColor.clearColor()
self.title = "二维码/条形码"
//设置标题颜色
let navigationTitleAttribute = NSDictionary(object: UIColor.whiteColor(), forKey: NSForegroundColorAttributeName)
self.navigationController?.navigationBar.titleTextAttributes = navigationTitleAttribute as? [String : AnyObject]
//1.返回
let backBtn = UIButton(type: UIButtonType.Custom)
backBtn.frame = CGRectMake(20, 30, 25, 25);
backBtn.setBackgroundImage(UIImage(named: "qrcode_scan_titlebar_back_nor"), forState:UIControlState.Normal);
backBtn.contentMode = UIViewContentMode.ScaleAspectFit
backBtn.addTarget(self, action: #selector(QRCodeScanViewController.backBtnAction), forControlEvents: UIControlEvents.TouchUpInside)
let backItem = UIBarButtonItem(customView: backBtn)
self.navigationItem.leftBarButtonItem = backItem
let editItem = UIBarButtonItem(barButtonSystemItem: .Edit, target: self, action: #selector(QRCodeScanViewController.editItemAction))
self.navigationItem.rightBarButtonItem = editItem
// deprecated //
// //2.相册
// let albumBtn = UIButton(type: UIButtonType.Custom)
// albumBtn.frame = CGRectMake(0, 0, 35, 49)
// albumBtn.center = CGPointMake(self.view.bounds.width / 2, 20 + 49 / 2.0)
// albumBtn.setBackgroundImage(UIImage(named: "qrcode_scan_btn_photo_down"), forState: UIControlState.Normal)
// albumBtn.contentMode=UIViewContentMode.ScaleAspectFit
// albumBtn.addTarget(self, action: #selector(QRCodeScanViewController.openAlbum), forControlEvents: UIControlEvents.TouchUpInside)// self.view.addSubview(albumBtn)
//
// //3.闪光灯
// let flashBtn = UIButton(type: UIButtonType.Custom)
// flashBtn.frame = CGRectMake(self.view.bounds.width - 55, 20, 35, 49)
// flashBtn.setBackgroundImage(UIImage(named: "qrcode_scan_btn_flash_down"), forState: UIControlState.Normal)
// flashBtn.contentMode=UIViewContentMode.ScaleAspectFit
// flashBtn.addTarget(self, action: #selector(QRCodeScanViewController.openFlash(_:)), forControlEvents: UIControlEvents.TouchUpInside)
// self.view.addSubview(flashBtn)
func editItemAction() {
let actionSheet = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
let action1 = UIAlertAction(title: "从相册选取二维码", style: .Default) {
[unowned self]
(act) in
self.openAlbum()
}
let action2 = UIAlertAction(title: "打开闪光灯", style: .Default) {
[unowned self]
(act) in
self.openFlash()
}
let action3 = UIAlertAction(title: "生成二维码", style: .Default) {
[unowned self]
(act) in
let inputVC = UIAlertController(title: "输入信息", message: nil, preferredStyle: .Alert)
let cancelAction = UIAlertAction(title: "取消", style: .Cancel, handler: nil)
let okayAction = UIAlertAction(title: "确定", style: .Default){
[unowned self]
(act) in
///生成二维码图片
let QRCodeImage = self.createQRCodeImage(withImage: UIImage(named: "icon_mine_default_portrait")!, string: self.textInfo!)
///展示在界面上
let imageBtn = UIButton(frame: CGRectMake(0, 64, SCREENWIDTH, SCREENHEIGHT - 64))
imageBtn.setImage(QRCodeImage, forState: .Normal)
imageBtn.addTarget(self, action: #selector(self.imageBtnAction(_:)), forControlEvents: .TouchUpInside)
imageBtn.backgroundColor = THEMECOLOR
self.view.addSubview(imageBtn)
///保存到相册
//UIImageWriteToSavedPhotosAlbum(QRCodeImage, self, #selector(self.image(_: didFinishSavingWithError: contextInfo: )), nil)
inputVC.dismissViewControllerAnimated(true, completion: {
print("生成二维码")
})
}
inputVC.addAction(cancelAction)
inputVC.addAction(okayAction)
inputVC.addTextFieldWithConfigurationHandler({ (textField) in
textField.borderStyle = .None
textField.placeholder = "输入需要保存的信息"
textField.delegate = self
textField.becomeFirstResponder()
})
self.presentViewController(inputVC, animated: true, completion: {
print("输入信息可以生成二维码")
})
}
let action4 = UIAlertAction(title: "取消", style: .Cancel, handler: nil)
actionSheet.addAction(action1)
actionSheet.addAction(action2)
actionSheet.addAction(action3)
actionSheet.addAction(action4)
self.presentViewController(actionSheet, animated: true, completion: nil)
}
1.3、遮罩(蒙板)的设置:setupMaskView()
let kMargin = CGFloat(50)
func setupMaskView() {
maskView = UIView()
maskView.layer.borderColor = UIColor(red: CGFloat(0), green: CGFloat(0), blue: CGFloat(0), alpha: CGFloat(0.7)).CGColor
maskView.layer.borderWidth = kMargin
let maskViewSize = CGSizeMake(self.view.extWidth(), self.view.extWidth())///正方形,下面会露出来,还要添加补充遮罩
maskView.frame = CGRectMake(0, 64, maskViewSize.width, maskViewSize.height)
self.view.addSubview(maskView)
///补充遮罩
let mask = UIView(frame: CGRectMake(0, maskView.extY() + maskView.extHeight(), SCREENWIDTH, SCREENHEIGHT - (maskView.extY() + maskView.extHeight())))
mask.backgroundColor = UIColor(red: CGFloat(0), green: CGFloat(0), blue: CGFloat(0), alpha: CGFloat(0.7))
self.view.addSubview(mask)
}
1.4、扫描区域的设置:setupScanWindowView()
func setupScanWindowView() {
let scanWindowH = maskView.extWidth() - kMargin * 2 ///kMargin为黑色边框的宽度,
let scanWindowW = scanWindowH
scanWindow = UIView(frame: CGRectMake(kMargin, kMargin + 64, scanWindowW, scanWindowH))///隐形的框
scanWindow.clipsToBounds = true
self.view.addSubview(scanWindow)
scanNetImageView = UIImageView(image: UIImage(named: "scan_net"))
scanNetImageView.extSetY(-1 * scanNetImageView.extHeight())
scanWindow.addSubview(scanNetImageView)
let buttonWH = CGFloat(18)
let topLift = UIImageView(frame: CGRectMake(0, 0, buttonWH, buttonWH))
topLift.image = UIImage(named: "scan_1")
let topRight = UIImageView(frame: CGRectMake(scanWindowW - buttonWH, 0, buttonWH, buttonWH))
topRight.image = UIImage(named: "scan_2")
let bottomLeft = UIImageView(frame: CGRectMake(0, scanWindowH - buttonWH, buttonWH, buttonWH))
bottomLeft.image = UIImage(named: "scan_3")
let bottomRight = UIImageView(frame: CGRectMake(topRight.frame.origin.x, bottomLeft.frame.origin.y, buttonWH, buttonWH))
bottomRight.image = UIImage(named: "scan_4")
scanWindow.addSubview(topLift)
scanWindow.addSubview(topRight)
scanWindow.addSubview(bottomLeft)
scanWindow.addSubview(bottomRight)
self.view.addSubview(scanWindow)
}
2、二维码的扫描
主要用的的是AVCaptureSession
类,然后设置input
和output
即可,值得一提的是扫码支持的类型:output.metadataObjectTypes
。iOS已经提供了很多,但是并不全,不过包含了常用的二维码AVMetadataObjectTypeQRCode
和条形码AVMetadataObjectTypeCode128Code
等
func beginScanning() {///要真机
///模拟图片动起来
///way 1、UIView Animation
UIView.animateWithDuration(1.5, delay: 0, options: UIViewAnimationOptions.Repeat, animations: {
[unowned self] in
self.scanNetImageView.transform = CGAffineTransformTranslate(self.scanNetImageView.transform, 0, self.scanWindow.extHeight())
}, completion: nil)
///way 2、coreAnimation
//初始化链接对象
session = AVCaptureSession()
//高质量采集率
session.sessionPreset = AVCaptureSessionPresetHigh
let preLayer = AVCaptureVideoPreviewLayer(session: session)///注意session存放的地方
preLayer.frame = self.view.bounds
self.view.layer.insertSublayer(preLayer, atIndex: 0)
/*
* AVCaptureDevice 获取摄像设备
* AVCaptureDeviceInput 创建输入流
* AVCaptureMetadataOutput 创建输出了
*/
let device = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo)
var input: AVCaptureDeviceInput?
do {
input = try AVCaptureDeviceInput(device: device)
///add input
}catch let error as NSError {
// 发生了错误
print(error.localizedDescription)
}
catch {
print("--input未知错误--")
}
///add input
session.addInput(input)
let output = AVCaptureMetadataOutput()
///add delegate
output.setMetadataObjectsDelegate(self, queue: dispatch_get_main_queue())//主队列(主线程)
///设置“感兴趣”区域(敏感区域)
let interestRect = preLayer.metadataOutputRectOfInterestForRect(scanWindow.frame)///扫描区 到 metadata输出区
///值等于CGRectMake(scanWindow.extY() / SCREENHEIGHT, scanWindow.extX() / SCREENWIDTH, scanWindow.extHeight() / SCREENHEIGHT, scanWindow.extWidth() / SCREENWIDTH)
///把一个在 preview layer 坐标系中的rect 转换成一个在 metadata output 坐标系中的rect
output.rectOfInterest = interestRect ///注意,这个并不是扫描区的坐标尺寸
session.addOutput(output)
//设置扫码支持的类型
output.metadataObjectTypes = [AVMetadataObjectTypeDataMatrixCode,
AVMetadataObjectTypeAztecCode,
AVMetadataObjectTypeQRCode,
AVMetadataObjectTypePDF417Code,
AVMetadataObjectTypeEAN13Code,
AVMetadataObjectTypeEAN8Code,
AVMetadataObjectTypeCode128Code]
///常用的码制有:PDF417二维条码、Datamatrix二维条码、QR Code、Code 49、Code 16K、Code one等,
///除了这些常见的二维条码之外,还有Vericode条码、Maxicode条码、CP条码、Codablock F条码、 Ultracode条码及Aztec条码。
///start grab
session.startRunning()
}
3、从相册中读取二维码
主要用到的是CIDetector
检测器类,然后获取feature
对象。
/***********照片读取**************/
func openAlbum(){//相册
if(UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.PhotoLibrary)){
///1.初始化相册拾取器
let pikController = UIImagePickerController()
///2.设置代理
pikController.delegate = self//两个代理
//3.设置资源:
/**
UIImagePickerControllerSourceTypePhotoLibrary,相册
UIImagePickerControllerSourceTypeCamera,相机
UIImagePickerControllerSourceTypeSavedPhotosAlbum,照片库
*/
pikController.sourceType = UIImagePickerControllerSourceType.SavedPhotosAlbum
//4.随便给他一个转场动画
pikController.modalTransitionStyle = UIModalTransitionStyle.FlipHorizontal
self.presentViewController(pikController, animated: true, completion: nil)
}else{
let alertVC = UIAlertController(title: "提示", message: "设备不支持访问相册,请在设置->隐私->照片中进行设置!", preferredStyle: UIAlertControllerStyle.Alert)
let action = UIAlertAction(title: "OK", style: .Cancel, handler: nil)
alertVC.addAction(action)
self.presentViewController(alertVC, animated: true, completion: nil)
}
}
///imagePickerControllerdelegate func
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
///1.获取选择的图片
let image = info[UIImagePickerControllerOriginalImage]
///2.初始化一个监测器
let detector = CIDetector(ofType: CIDetectorTypeQRCode, context: nil, options: [ CIDetectorAccuracy : CIDetectorAccuracyHigh ])
picker.dismissViewControllerAnimated(true) { () -> Void in
///监测到的结果数组
let features = detector.featuresInImage(CIImage(CGImage: (image?.CGImage)!))
if features.count >= 1 {
/**结果对象 */
///CIQRCodeFeature
let feature = features[0] as! CIQRCodeFeature
let scannedResult = feature.messageString
let alertVC = UIAlertController(title: "提示", message: scannedResult, preferredStyle: UIAlertControllerStyle.Alert)
self.presentViewController(alertVC, animated: true, completion: nil)
}else {
let alertVC = UIAlertController(title: "提示", message: "该图片没有包含一个二维码!", preferredStyle: UIAlertControllerStyle.Alert)
let action = UIAlertAction(title: "OK", style: .Cancel, handler: nil)
alertVC.addAction(action)
self.presentViewController(alertVC, animated: true, completion: nil)
}
}
}
4、生成二维码
生成二维码处理过程有点复杂,首先要导入CoreImage
,然后用CIFilter
生成图片,name
为CIQRCodeGenerator
就是二维码滤镜,CICode128BarcodeGenerator
就是条形码滤镜,当然还有很多滤镜,如下面会用到的颜色滤镜name
为CIFalseColor
。
4.1、原生二维码的生成
/***********生成二维码图片**************/ ///coreImage
func createQRCodeImage(withImage image: UIImage, string: String) -> UIImage {
/// 1. 实例化二维码滤镜
let filter = CIFilter(name: "CIQRCodeGenerator")///CICode128BarcodeGenerator ///条形码
///注意
/// 2. 恢复滤镜的默认属性
filter?.setDefaults()
/// 3. 将字符串转换成二进制数据,(生成二维码所需的数据)
let data = string.dataUsingEncoding(NSUTF8StringEncoding)
/// 4. 通过KVO把二进制数据添加到滤镜inputMessage中
filter?.setValue(data, forKey: "inputMessage")
filter?.setValue("H", forKey: "inputCorrectionLevel")
/// 5. 获得滤镜输出的图像
let outputImage = filter?.outputImage ///CIImage
/// 6. 将CIImage转换成UIImage,并放大显示
//let originQRCodeImage = UIImage(CIImage: outputImage!, scale: 0.07, orientation: UIImageOrientation.Up) ///原生二维码图片 ///这样将图片放大会变得模糊
//return originQRCodeImage
///进行重绘
let newQRCodeImage = createUIimageWithCGImage(ciImage: outputImage!, widthAndHeightValue: 300)
return newQRCodeImage
}
如果你直接用这行代码返回图片
let originQRCodeImage = UIImage(CIImage: outputImage!, scale: 0.07, orientation: UIImageOrientation.Up) ///原生二维码图片 ///这样将图片放大会变得模糊
return originQRCodeImage
得到的图片将会很模糊,因为这是将图片进行放大了,但图片将0.07改为了1,看到的图片将会很小。
所以还得处理一下:
func createUIimageWithCGImage(ciImage image: CIImage, widthAndHeightValue wh: CGFloat) -> UIImage {
let ciRect = CGRectIntegral(image.extent)///根据容器得到适合的尺寸
let scale = min(wh / ciRect.width, wh / ciRect.height)
///获取bitmap
let width = size_t(ciRect.width * scale)
let height = size_t(ciRect.height * scale)
let cs = CGColorSpaceCreateDeviceGray()///灰度颜色通道 ///CGColorSpaceRef
let info_UInt32 = CGImageAlphaInfo.None.rawValue
let bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, info_UInt32)
let contex = CIContext(options: nil)
let bitmapImageRef = contex.createCGImage(image, fromRect: CGRectMake(ciRect.origin.x, ciRect.origin.y, ciRect.size.width, ciRect.size.height)) ///CGImageRef
CGContextSetInterpolationQuality(bitmapRef, CGInterpolationQuality.High)///写入质量高,时间长
CGContextScaleCTM(bitmapRef, scale, scale) ///调整“画布”的缩放
CGContextDrawImage(bitmapRef, ciRect, bitmapImageRef) ///绘制图片
///保存
let scaledImage = CGBitmapContextCreateImage(bitmapRef)
///bitmapRef和bitmapImageRef不用主动释放,Core Foundation自动管理
//let originImage = UIImage(CGImage: scaledImage!) ///原生灰度图片(灰色)
let ciImage = CIImage(CGImage: scaledImage!)
///添加滤镜
let colorFilter = CIFilter(name: "CIFalseColor")///颜色滤镜
colorFilter!.setDefaults()
colorFilter!.setValue(ciImage, forKey:kCIInputImageKey)
colorFilter!.setValue(CIColor(red: 33.0 / 225.0, green: 192.0 / 225.0, blue: 174.0 / 225.0, alpha: 1.0), forKey:"inputColor0")///二维码元素(像素)
colorFilter!.setValue(CIColor(red: 1.0, green: 1.0, blue: 1.0, alpha: 1), forKey:"inputColor1")///背景
let colorImgae = colorFilter!.outputImage
let newQRCodeImage = UIImage(CIImage: colorImgae!)
return newQRCodeImage
}
这样将会得到彩色的二维码,效果也还不错,这里又添加colorFilter这样滤镜,达到着色的效果。iOS其实可以混合多个滤镜来实现很多不能的效果,手机自带的图片处理就是基于滤镜来完成,如果你有使用过PS,或了解过知识,这就很容易理解了。如果去掉这部分代码得到的将会是灰色的图片。
其实重新着色,还可以通过,context来重绘或者通过改变每个像素的的颜色值来达到目的,但是难度会远比添加一个滤镜要复杂的多,而且,Swift中通过指针来处理数据,写法将会更加复杂,这是因为Swift是一门语法安全性语言。也没有*P这样的写法。
关于CIFilter的更多知识,我就会在后续文章中分享,你们也可以通过资料去学习,总之,这部分知识还是很容易理解的,也比较有趣。
更新的CIFilter文章:点击这里 会教你获取更清晰的二维码。
最后,想了解更多详情:请查看我的demo,记得给个Star,😝😝😝
下载:点击这里