iOS系统原生二维码条形码扫描

　1.在工程中添加框架AVFoundation.framework

　　2.声明代理：AVCaptureMetadataOutputObjectsDelegate 。 define 几个东东用来画框、画线：

#define SCANVIEW_EdgeTop 40.0#define SCANVIEW_EdgeLeft 50.0#define TINTCOLOR_ALPHA 0.2 //浅色透明度#define DARKCOLOR_ALPHA 0.5 //深色透明度#define VIEW_WIDTH [UIScreen mainScreen].bounds.size.width#define VIEW_HEIGHT [UIScreen mainScreen].bounds.size.height

 

　　3.声明以下属性：

    AVCaptureSession * session;//输入输出的中间桥梁    UIView *AVCapView;//此 view 用来放置扫描框、取消按钮、说明 label    UIView *_QrCodeline;//上下移动绿色的线条    NSTimer *_timer;

　　4.在某个方法中（我是点击扫描按钮）创建扫描界面，开始扫描：

 //创建一个 view 来放置扫描区域、说明 label、取消按钮    UIView *tempView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, [UIScreen mainScreen].bounds.size.height )];    AVCapView = tempView;    AVCapView.backgroundColor = [UIColor colorWithRed:54.f/255 green:53.f/255 blue:58.f/255 alpha:1];        UIButton *cancelBtn = [[UIButton alloc]initWithFrame:CGRectMake(15, [UIScreen mainScreen].bounds.size.height - 100, 50, 25)];    UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(15, 268, 290, 60)];    label.numberOfLines = 0;    label.text = @"小提示：将条形码或二维码对准上方区域中心即可";    label.textColor = [UIColor grayColor];    [cancelBtn setTitle:@"取消" forState: UIControlStateNormal];    [cancelBtn setTitleColor:[UIColor grayColor] forState:UIControlStateNormal];    [cancelBtn addTarget:self action:@selector(touchAVCancelBtn) forControlEvents:UIControlEventTouchUpInside];    [AVCapView addSubview:label];    [AVCapView addSubview:cancelBtn];    [self.view addSubview:AVCapView];            //画上边框    UIView *topView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop, VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft, 1)];    topView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:topView];        //画左边框    UIView *leftView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop , 1,VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft )];    leftView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:leftView];        //画右边框    UIView *rightView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft + VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop , 1,VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + 1)];    rightView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:rightView];        //画下边框    UIView *downView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop + VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft,VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft ,1 )];    downView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:downView];        //画中间的基准线    _QrCodeline = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft + 1, SCANVIEW_EdgeTop, VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft - 1, 2)];    _QrCodeline.backgroundColor = [UIColor greenColor];    [AVCapView addSubview:_QrCodeline];            // 先让基准线运动一次，避免定时器的时差    [UIView animateWithDuration:1.2 animations:^{                _QrCodeline.frame = CGRectMake(SCANVIEW_EdgeLeft + 1, VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + SCANVIEW_EdgeTop , VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft - 1, 2);            }];    [self performSelector:@selector(createTimer) withObject:nil afterDelay:0.4];        AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];    //创建输入流    AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];    //创建输出流    AVCaptureMetadataOutput * output = [[AVCaptureMetadataOutput alloc]init];    //设置代理 在主线程里刷新    [output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];        //初始化链接对象    session = [[AVCaptureSession alloc]init];    //高质量采集率    [session setSessionPreset:AVCaptureSessionPresetHigh];        [session addInput:input];    [session addOutput:output];    //设置扫码支持的编码格式(如下设置条形码和二维码兼容)    output.metadataObjectTypes=@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code];        AVCaptureVideoPreviewLayer * layer = [AVCaptureVideoPreviewLayer layerWithSession:session];    layer.videoGravity=AVLayerVideoGravityResizeAspectFill;    layer.frame = CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop, VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft, 220);    [AVCapView.layer insertSublayer:layer atIndex:0];    //开始捕获    [session startRunning];

　　5.实现定时器、还有基准线的滚动方法

- (void)createTimer{    _timer=[NSTimer scheduledTimerWithTimeInterval:1.1 target:self selector:@selector(moveUpAndDownLine) userInfo:nil repeats:YES];}- (void)stopTimer{    if ([_timer isValid] == YES) {        [_timer invalidate];        _timer = nil;    }    }// 滚来滚去 :D :D :D- (void)moveUpAndDownLine{    CGFloat YY = _QrCodeline.frame.origin.y;        if (YY != VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + SCANVIEW_EdgeTop ) {        [UIView animateWithDuration:1.2 animations:^{            _QrCodeline.frame = CGRectMake(SCANVIEW_EdgeLeft + 1, VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + SCANVIEW_EdgeTop , VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft - 1,2);        }];    }else {        [UIView animateWithDuration:1.2 animations:^{            _QrCodeline.frame = CGRectMake(SCANVIEW_EdgeLeft + 1, SCANVIEW_EdgeTop, VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft - 1,2);        }];    }}

6.扫描成功后，想干嘛干嘛，就在这个代理方法里面实现就行了

-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{    if (metadataObjects.count>0) {        //[session stopRunning];        AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjects objectAtIndex : 0 ];        //输出扫描字符串        NSLog(@"%@",metadataObject.stringValue);        [session stopRunning];        [self stopTimer];        [AVCapView removeFromSuperview];        .....        }}

 

7.如果用户不想扫描了，点击取消按钮：

- (void)touchAVCancelBtn{    [session stopRunning];//摄像也要停止    [self stopTimer];//定时器要停止    [AVCapView removeFromSuperview];//刚刚创建的 view 要移除       ...