原生二维码的运用

 1   // 1.获取输入设备(摄像头)
 2     AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
 3     // 2.根据输入设备创建输入对象
 4     AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:NULL];
 5     
 6     if (input==nil) {
 7         return;
 8     }
 9     // 3.创建输出对象
10     AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc] init];
11     // 4.设置代理监听输出对象输出的数据
12     [output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
13     
14     // 5.创建会话(桥梁)
15     AVCaptureSession *session = [[AVCaptureSession alloc] init];
16     // 6.添加输入和输出到会话中（判断session是否已满）
17     if ([session canAddInput:input]) {
18         [session addInput:input];
19     }
20     if ([session canAddOutput:output]) {
21         [session addOutput:output];
22     }
23     // 7.告诉输出对象, 需要输出什么样的数据 (二维码还是条形码)
24     output.metadataObjectTypes =@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeCode128Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeUPCECode,AVMetadataObjectTypeCode39Code,AVMetadataObjectTypePDF417Code,AVMetadataObjectTypeAztecCode,AVMetadataObjectTypeCode93Code,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeCode39Mod43Code];
25     
26     // 8.创建预览图层
27     AVCaptureVideoPreviewLayer *previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:session];
28     [previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
29     previewLayer.frame = self.view.bounds;
30     [self.view.layer insertSublayer:previewLayer atIndex:0];
31     
32     //设置感应区域
33 //    CGRect rect = CGRectMake((WIDTH_FULL_SCREEN - imageSize) / 2, originalTop, imageSize, imageSize);
34 //    CGRect intertRect = [previewLayer metadataOutputRectOfInterestForRect:rect];
35 //    CGRect layerRect = [previewLayer rectForMetadataOutputRectOfInterest:intertRect];
36 //    NSLog(@"%@,  %@",NSStringFromCGRect(intertRect),NSStringFromCGRect(layerRect));
37 //    output.rectOfInterest = layerRect;//[previewLayer metadataOutputRectOfInterestForRect:rect];
38     
39     // 8.开始扫描数据
40     [session startRunning];
41     self.session = session;
42     
43     //设置中空区域
44     UIView *maskView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, WIDTH_FULL_SCREEN, HEIGHT_FULL_VIEW)];
45     maskView.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.4];
46     [self.view addSubview:maskView];
47     [self.view bringSubviewToFront:self.flashButton];
48     UIBezierPath *rectPath = [UIBezierPath bezierPathWithRect:CGRectMake(0, 0, WIDTH_FULL_SCREEN, HEIGHT_FULL_VIEW)];
49     [rectPath appendPath:[[UIBezierPath bezierPathWithRoundedRect:CGRectMake((WIDTH_FULL_SCREEN - imageSize) / 2, originalTop, imageSize, imageSize) cornerRadius:1] bezierPathByReversingPath]];
50     CAShapeLayer *shapeLayer = [CAShapeLayer layer];
51     shapeLayer.path = rectPath.CGPath;
52     maskView.layer.mask = shapeLayer;
53 }
54 
55 #pragma mark - AVCaptureMetadataOutputObjectsDelegate
56 // 扫描到数据时会调用
57 - (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{
58     if (metadataObjects.count > 0) {
59         // 1.停止扫描
60         [self.session stopRunning];
61         // 2.停止冲击波
62         [self.link removeFromRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];
63          
64         // 3.取出扫描到得数据
65         AVMetadataMachineReadableCodeObject *obj = [metadataObjects lastObject];
66         
67         //处理结果
68         UIAlertController *alertCtrl = [UIAlertController alertControllerWithTitle:@"扫描结果" message:[obj stringValue] preferredStyle:UIAlertControllerStyleAlert];
69         [alertCtrl addAction:[UIAlertAction actionWithTitle:@"确认" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
70             [self.session startRunning];
71             [self.link addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];
72         }]];
73         [self presentViewController:alertCtrl animated:YES completion:nil];
74     }
75 }