代码地址如下：
http://www.demodashi.com/demo/12551.html

一、效果预览：

功能描述:WSLNativeScanTool是在利用原生API的条件下封装的二维码扫描工具，支持二维码的扫描、识别图中二维码、生成自定义颜色和中心图标的二维码、监测环境亮度、打开闪光灯这些功能；WSLScanView是参照微信封装的一个扫一扫界面，支持线条颜色、大小、动画图片、矩形扫描框样式的自定义；这个示例本身就是仿照微信的扫一扫功能实现的。

二、实现

主要代码如下：

• 初始化扫描识别对象

- (AVCaptureSession *)session{if (_session == nil){//获取摄像设备AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];//创建输入流AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];if (!input){return nil;}//创建二维码扫描输出流AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc] init];//设置代理 在主线程里刷新[output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];//设置采集扫描区域的比例 默认全屏是（0，0，1，1）//rectOfInterest 填写的是一个比例，输出流视图preview.frame为 x , y, w, h, 要设置的矩形快的scanFrame 为 x1, y1, w1, h1. 那么rectOfInterest 应该设置为 CGRectMake(y1/y, x1/x, h1/h, w1/w)。CGFloat x = CGRectGetMinX(self.scanFrame)/ CGRectGetWidth(self.preview.frame);CGFloat y = CGRectGetMinY(self.scanFrame)/ CGRectGetHeight(self.preview.frame);CGFloat width = CGRectGetWidth(self.scanFrame)/ CGRectGetWidth(self.preview.frame);CGFloat height = CGRectGetHeight(self.scanFrame)/ CGRectGetHeight(self.preview.frame);output.rectOfInterest = CGRectMake(y, x, height, width);// 创建环境光感输出流AVCaptureVideoDataOutput *lightOutput = [[AVCaptureVideoDataOutput alloc] init];[lightOutput setSampleBufferDelegate:self queue:dispatch_get_main_queue()];_session = [[AVCaptureSession alloc] init];//高质量采集率[_session setSessionPreset:AVCaptureSessionPresetHigh];[_session addInput:input];[_session addOutput:output];[_session addOutput:lightOutput];//设置扫码支持的编码格式(这里设置条形码和二维码兼容)output.metadataObjectTypes = @[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeCode128Code];}return _session;
}

• 扫描出结果的代理方法

#pragma mark -- AVCaptureMetadataOutputObjectsDelegate
//扫描完成后执行
-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{if (metadataObjects.count > 0){AVMetadataMachineReadableCodeObject *metadataObject = [metadataObjects firstObject];// 扫描完成后的字符//        NSLog(@"扫描出 %@",metadataObject.stringValue);if(self.scanFinishedBlock != nil){self.scanFinishedBlock(metadataObject.stringValue);}}
}
#pragma mark- AVCaptureVideoDataOutputSampleBufferDelegate的方法
//扫描过程中执行，主要用来判断环境的黑暗程度
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection{if (self.monitorLightBlock == nil) {return;}CFDictionaryRef metadataDict = CMCopyDictionaryOfAttachments(NULL,sampleBuffer, kCMAttachmentMode_ShouldPropagate);NSDictionary *metadata = [[NSMutableDictionary alloc] initWithDictionary:(__bridge NSDictionary*)metadataDict];CFRelease(metadataDict);NSDictionary *exifMetadata = [[metadata objectForKey:(NSString *)kCGImagePropertyExifDictionary] mutableCopy];float brightnessValue = [[exifMetadata objectForKey:(NSString *)kCGImagePropertyExifBrightnessValue] floatValue];//    NSLog(@"环境光感 ： %f",brightnessValue);// 根据brightnessValue的值来判断是否需要打开和关闭闪光灯AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];BOOL result = [device hasTorch];// 判断设备是否有闪光灯if ((brightnessValue < 0) && result) {// 环境太暗，可以打开闪光灯了}else if((brightnessValue > 0) && result){// 环境亮度可以}if (self.monitorLightBlock != nil) {self.monitorLightBlock(brightnessValue);}}

三、用法

• 实例化WSLNativeScanTool工具类和WSLScanView界面类；用法很简单，头文件里注释的也挺详细的。

//输出流视图UIView *preview  = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height - 0)];[self.view addSubview:preview];__weak typeof(self) weakSelf = self;//构建扫描样式视图_scanView = [[WSLScanView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height - 0)];_scanView.scanRetangleRect = CGRectMake(60, 120, (self.view.frame.size.width - 2 * 60),  (self.view.frame.size.width - 2 * 60));_scanView.colorAngle = [UIColor greenColor];_scanView.photoframeAngleW = 20;_scanView.photoframeAngleH = 20;_scanView.photoframeLineW = 2;_scanView.isNeedShowRetangle = YES;_scanView.colorRetangleLine = [UIColor whiteColor];_scanView.notRecoginitonArea = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.5];_scanView.animationImage = [UIImage imageNamed:@"scanLine"];_scanView.myQRCodeBlock = ^{[WSLNativeScanTool createQRCodeImageWithString:@"https://www.jianshu.com/u/e15d1f644bea" andSize:CGSizeMake(250, 250) andBackColor:[UIColor whiteColor] andFrontColor:[UIColor orangeColor] andCenterImage:[UIImage imageNamed:@"piao"]];createQRCodeController.qrString = @"https://www.jianshu.com/u/e15d1f644bea";};_scanView.flashSwitchBlock = ^(BOOL open) {[weakSelf.scanTool openFlashSwitch:open];};[self.view addSubview:_scanView];//初始化扫描工具_scanTool = [[WSLNativeScanTool alloc] initWithPreview:preview andScanFrame:_scanView.scanRetangleRect];_scanTool.scanFinishedBlock = ^(NSString *scanString) {NSLog(@"扫描结果 %@",scanString);[weakSelf.scanTool sessionStopRunning];[weakSelf.scanTool openFlashSwitch:NO];};_scanTool.monitorLightBlock = ^(float brightness) {NSLog(@"环境光感 ： %f",brightness);if (brightness < 0) {// 环境太暗，显示闪光灯开关按钮[weakSelf.scanView showFlashSwitch:YES];}else if(brightness > 0){// 环境亮度可以,且闪光灯处于关闭状态时，隐藏闪光灯开关if(!weakSelf.scanTool.flashOpen){[weakSelf.scanView showFlashSwitch:NO];}}};[_scanTool sessionStartRunning];[_scanView startScanAnimation];

四、项目结构

五、其他补充

暂没
iOS 原生二维码扫描和生成

代码地址如下：
http://www.demodashi.com/demo/12551.html

注：本文著作权归作者，由demo大师代发，拒绝转载，转载需要作者授权