iOS7+ 扫描二维码和条形码实现 耗时操作

iOS7以前都是用Zxing Zbar 来实现 扫描二维码以及条形码,从iOS7 出来后,系统自带API很强大,渐渐也就放弃了Zxing Zbar的使用,

直接上主要代码:

- (void)setupCamera

{

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

        [HUDUtils showHUDProgress:@""];

    AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];

        if (authStatus == AVAuthorizationStatusAuthorized) {//已经授权

        }else { //没有授权

            NSString *recommand;

            if (IS_IOS_8) {

                recommand = @"无法打开相机,请去设置中打开后继续操作\n设置->好点商家->相机";

            }else{

                recommand = @"无法接收推送消息,请去设置中打开后继续操作\n设置->隐私->相机->好点商家";

            }

            UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"提示" message:recommand delegate:nil cancelButtonTitle:@"确定" otherButtonTitles: nil];

            [alert show];

            return;

        }

        /// Device

        _device  = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

        // Input

        _input   = [AVCaptureDeviceInput deviceInputWithDevice:self.device error:nil];

        // Output

        _output  = [[AVCaptureMetadataOutput alloc] init];

        [_output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];

        _output.rectOfInterest = self.scanImageView.bounds;

        // Session

        _session = [[AVCaptureSession alloc]init];

        [_session setSessionPreset:AVCaptureSessionPresetHigh];

        if ([_session canAddInput:self.input])

        {

            [_session addInput:self.input];

        }

        if ([_session canAddOutput:self.output])

        {

            [_session addOutput:self.output];

        }

        // 条码类型 AVMetadataObjectTypeQRCode

        _output.metadataObjectTypes =@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeUPCECode];

    dispatch_async(dispatch_get_main_queue(), ^{

    // Preview

        [HUDUtils dismiss];

        _preview =[AVCaptureVideoPreviewLayer layerWithSession:self.session];

        _preview.videoGravity = AVLayerVideoGravityResizeAspectFill;

        _preview.frame        = self.view.frame;

        [self.view.layer insertSublayer:self.preview atIndex:0];

        /* 配置取景框之外颜色开始 */

        // scanCrop

        UIView *viewTopScan =

        [[UIView alloc] initWithFrame:CGRectMake(0, 0, ScreenWidth, self.scanImageView.top)];

        UIView *viewBottomScan =

        [[UIView alloc] initWithFrame:CGRectMake(0, self.scanImageView.bottom,

                                             ScreenWidth,

                                             ScreenHeight - self.scanImageView.bottom)];

        UIView *viewLeftScan =

        [[UIView alloc] initWithFrame:CGRectMake(0, self.scanImageView.top, (ScreenWidth-self.scanImageView.width)/2, self.scanImageView.height)];

        UIView *viewRightScan =

        [[UIView alloc] initWithFrame:CGRectMake(self.scanImageView.right,

                                             self.scanImageView.top,

                                             (ScreenWidth-self.scanImageView.width)/2,

                                             self.scanImageView.height)];

        viewTopScan.backgroundColor = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.2];

        viewBottomScan.backgroundColor = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.2];

        viewLeftScan.backgroundColor = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.2];

        viewRightScan.backgroundColor = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.2];

        [self.view addSubview:viewTopScan];

        [self.view addSubview:viewBottomScan];

        [self.view addSubview:viewLeftScan];

        [self.view addSubview:viewRightScan];

        /* 配置取景框之外颜色结束 */

        self.contentLable.layer.cornerRadius = self.contentLable.height / 2 ;

        self.contentLable.layer.backgroundColor = [[UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.8] CGColor];

        // Start

        [_session startRunning];

        });

    });

}

有一点需要注意,在初始化相机的时候,会耗时,在iPhone 4 机器上体现的尤为明显,也很简单,加上一个异步操作解决问题.