iOS二维码扫描

每一步：添加 AVFoundation.framework 库

General > Linked Frameworks and Libraries

第二步：实现代码

#import "ViewController.h"

#import <AVFoundation/AVFoundation.h>

@interface ViewController ()<AVCaptureMetadataOutputObjectsDelegate>

/** 2.输入设置采集摄像头捕捉到的信息 */

@property (nonatomic,strong) AVCaptureDeviceInput *input;

/** 3.输出设备解析输入设备采集到的信息 */

@property (nonatomic,strong) AVCaptureMetadataOutput *output;

/** 4. layer (特殊图层能够展示摄像头采集到的画面)展示输入设备采集到的信息 */

@property (nonatomic,strong) AVCaptureVideoPreviewLayer *layer;

/** 5.关联输入设备和输出设备会话 */

@property (nonatomic,strong) AVCaptureSession *session;

@end

@implementation ViewController

- (void)viewDidLoad {

    [superviewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

}

// 点击扫描二维码

- (IBAction)click:(id)sender {

    

    // 1.创建输入设备

    //     AVMediaTypeVideo 摄像头

    //     AVMediaTypeAudio 麦克风

    //     AVCaptureDeviceInput 输入设备    default默认后置

    //    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

    NSArray *allDevice = [AVCaptureDevicedevicesWithMediaType:AVMediaTypeVideo];

    

    self.input = [AVCaptureDeviceInputdeviceInputWithDevice:[allDevicefirstObject] error:nil];

    

    //2. 创建输出设备

    self.output = [[AVCaptureMetadataOutputalloc]init];

    //解析返回的数据

    

    //设置输出设备的代理返回解析后的数据

    [self.outputsetMetadataObjectsDelegate:selfqueue:dispatch_get_main_queue()];

    //3.创建会话

    self.session = [[AVCaptureSessionalloc]init];

    //4.关联会话和设备

    if ([self.sessioncanAddInput:self.input]) {

        [self.sessionaddInput:self.input];

    }

    if ([self.sessioncanAddOutput:self.output]) {

        [self.sessionaddOutput:self.output];

    }

    //告诉数据类型  AVMetadataObjectTypeQRCode二维码

    self.output.metadataObjectTypes = @[AVMetadataObjectTypeQRCode];

    // 扫描框大小 整个屏幕

    [self.sessionsetSessionPreset:AVCaptureSessionPreset640x480];

    //5.指定layer的 frame 然后添加到 view上

    self.layer = [[AVCaptureVideoPreviewLayeralloc]initWithSession:self.session];

    self.layer.frame =self.view.bounds;

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

    //开启会话

    [self.sessionstartRunning];

}

//扫描出结果后就会调用的代理方法方法

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

    AVMetadataMachineReadableCodeObject *objc = [metadataObjectsfirstObject];

    NSString *str = objc.stringValue;

    

    NSLog(@"%@",str);

    //停止扫描

    [self.sessionstopRunning];

    

    //移除 layer

    [self.layerremoveFromSuperlayer];

}

@end