iOS---扫码

我在两个项目中分别使用了ZBarSDK与系统自带的扫码，今天主要介绍一下系统自带的扫码。

1。系统自带的

（1）先声明两个属性

@property (nonatomic,strong)AVCaptureSession *session; //捕捉会话

@property (nonatomic,strong)AVCaptureVideoPreviewLayer *layer; //扫描图层

（2）添加输入设备并检查设备是否支持相机

//添加输入设备并创建捕捉会话

AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

self.session = [[AVCaptureSession alloc] init];

AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];

NSError *error=nil;

if (input) {

[self.session addInput:input];

}else{

NSLog(@"获取摄像设备error:%@",[error localizedDescription]);

}

//检查相机状态

AVAuthorizationStatus status = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];

if(status == AVAuthorizationStatusAuthorized) {

[self setupCamera];

} else {

[self showStr:@"您没有权限访问相机" withSelf:self withMinier:2.0];

}

(3)在能打开相机的情况下创扫描图层

//添加输出数据

AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc] init];

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

//高质量采集率

[self.session setSessionPreset:AVCaptureSessionPresetHigh];

[self.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 setMetadataObjectTypes:@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code]];

//添加扫描图层

self.layer = [AVCaptureVideoPreviewLayer layerWithSession:self.session];

self.layer.frame = CGRectMake((ScreenWidth-250)/2,ScreenHeight*0.25, 250, 250);

self.layer.videoGravity = AVLayerVideoGravityResizeAspectFill;

[self.view.layer addSublayer:self.layer];

(4)开始扫描

[self.session startRunning];

(5)如果扫描到数据会调用代理方法 （遵守AVCaptureMetadataOutputObjectsDelegate协议）

- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection {  }

   注意：xcode8的 用户在使用这个功能的时候要先再plist。info 中添加项： Privacy - Camera Usage Description     是否允许此App使用你的相机?

2.ZBarSDK

    参考自：http://www.mincoder.com/article/4419.shtml