IOS 二维码扫描

//
//  ViewController.m
//  CX 二维码扫描
//
//  Created by ma c on 16/4/12.
//  Copyright © 2016年 bjsxt. All rights reserved.
//

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

@end

@implementation ViewController

- (void)viewDidLoad {

}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

//创建捕捉会话
AVCaptureSession * session = [[AVCaptureSession alloc]init];
//添加输入设备
AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:@"AVMediaTypeVideo"];
AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
[session addInput:input];
//添加输出数据
AVCaptureMetadataOutput * output = [[AVCaptureMetadataOutput alloc]init];
[output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
[session addOutput:output];
//告诉元数据类型为二维码类型
//注意该方法在add后 否则崩溃
//测试需要真机稍有麻烦 就不截图了
[output setMetadataObjectTypes:@[AVMetadataObjectTypeQRCode]];
//添加扫描图层
AVCaptureVideoPreviewLayer *layer = [AVCaptureVideoPreviewLayer layerWithSession:session];
layer.frame = CGRectMake(10,20, self.view.frame.size.width, 400);
[self.view.layer addSublayer:layer];
//开始扫描
[session startRunning];

//下面的方法适当的时候操作
//停止扫描
//    [session stopRunning];
//移除图层
//    [layer removeFromSuperlayer];
}
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{
//metadataObjects 为扫描的后的数据

AVMetadataMachineReadableCodeObject * objc = [metadataObjects lastObject];
//我们想要的结果
NSLog(@"%@",objc.stringValue);
}
@end