ios实现二维码扫描

1 包含

#import <AVFoundation/AVFoundation.h>

2 导入AVFoundation库文件

#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>
@interface ViewController ()<AVCaptureMetadataOutputObjectsDelegate>
- (IBAction)scan:(UIButton *)sender;
@property (strong,nonatomic)AVCaptureDevice *device;
@property (strong,nonatomic)AVCaptureDeviceInput *input;
@property (strong,nonatomic)AVCaptureMetadataOutput *output;
@property (strong,nonatomic)AVCaptureSession *session;
@property (strong,nonatomic)AVCaptureVideoPreviewLayer *preview;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
}

- (void)setupCamera
{
    // 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()];
    
    // 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];
    
    // Preview
    _preview =[AVCaptureVideoPreviewLayer layerWithSession:self.session];
    _preview.videoGravity = AVLayerVideoGravityResizeAspectFill;
    _preview.frame =CGRectMake(20,110,280,280);
    [self.view.layer insertSublayer:self.preview atIndex:0];
    
    
    
    // Start
    [_session startRunning];
}
#pragma mark AVCaptureMetadataOutputObjectsDelegate
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection
{
    NSString *stringValue = [[NSString alloc] init];
    
    if (metadataObjects.count >0) {
        AVMetadataMachineReadableCodeObject *metadataObject = [metadataObjects objectAtIndex:0];
        stringValue = metadataObject.stringValue;
    }
    
    [_session stopRunning];
    NSLog(@"%@",stringValue);
    [self dismissViewControllerAnimated:YES completion:^{
        UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil
                                                      message:stringValue
                                                     delegate:nil
                                            cancelButtonTitle:@"OK"
                                            otherButtonTitles:nil,nil];
        [alert show];
    }];
}
- (IBAction)scan:(UIButton *)sender {
    [self setupCamera];
}

有待完善。。。。。