iOS设置和获取条形码

//
//  Copyright © 2016年 hjl. All rights reserved.
//

#import "HHBarcodeViewController.h"
#import <AVFoundation/AVFoundation.h>
@interface HHBarcodeViewController ()

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

//* 预览图层 */
@property (nonatomic, weak) AVCaptureVideoPreviewLayer *previewLayer;
@end

@implementation HHBarcodeViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    // 条形码页面动画
    CADisplayLink *disp = [CADisplayLink displayLinkWithTarget:self selector:@selector(update)];

    [disp addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];
    // 1. 实例化拍摄设备
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    // 2. 设置输入设备
    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
    // 3. 实例化拍摄元数据输出
    AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc] init];
    // 4. 设置输出数据代理
    [output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
    // 5. 添加拍摄会话
    AVCaptureSession *session = [[AVCaptureSession alloc] init];
    self.session = session;
    // 6. 添加会话输入/输出
    if ([session canAddInput:input]) {
        [session addInput:input];
    }
    if ([session canAddOutput:output]) {
        [session addOutput:output];
    }
    //7 设置输出数据类型，需要将元数据输出添加到会话后，才能指定元数据类型，否则会报错
    [output setMetadataObjectTypes:@[
            AVMetadataObjectTypeUPCECode,
            AVMetadataObjectTypeCode39Code,
            AVMetadataObjectTypeCode39Mod43Code,
            AVMetadataObjectTypeEAN13Code,
            AVMetadataObjectTypeEAN8Code,
            AVMetadataObjectTypeCode93Code,
            AVMetadataObjectTypeCode128Code,
            AVMetadataObjectTypePDF417Code,
            AVMetadataObjectTypeAztecCode,
            AVMetadataObjectTypeInterleaved2of5Code,
            AVMetadataObjectTypeITF14Code,
            AVMetadataObjectTypeDataMatrixCode,
            ]];
    //8 实例化预览图层
    AVCaptureVideoPreviewLayer *previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:session];
    previewLayer.frame = self.view.bounds;
    self.previewLayer = previewLayer;
    //previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
    //9 将图层插入当前视图
    [self.view.layer insertSublayer:previewLayer atIndex:0];
    //10 启动会话
    [_session startRunning];

}

#pragma 代理
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{

    //1 判断是否获取到数据
    if (metadataObjects.count > 0) {
        //2 停止刷新
        [self.session stopRunning];
        //3 移除预览图层
        [self.previewLayer removeFromSuperlayer];
        //4 读取数据
        AVMetadataMachineReadableCodeObject *obj = [metadataObjects lastObject];
        HHLog(@"%@", obj.stringValue);
    }

}

- (void)update{
    _barcodeConsY.constant += 3;
    if(_barcodeConsY.constant >= 224){
        _barcodeConsY.constant = 0;
    }
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
@end