iOS二维码扫描

测试环境：iPhone 5s  iOS7.1

首先添加框架AVFoundation.framework，然后导入自定义类CMCaptureViewController.h、CMCaptureViewController.m，以及用到的图片资源：line@2x.png、pick_bg@2x.png。

用的时候只需要切换到二维码视图控制器CMCaptureViewController即可，会跳到二维码扫描界面

如：

[self presentViewController:captureViewController animated:YES completion:nil];

要获得扫描的二维码内容，只需要成为其委托，实现委托方法

- (void)captureController:(CMCaptureViewController *)controller data:(id)metadata;

参数metadata中包含扫描到的字符串。

CMCaptureViewController.h、CMCaptureViewController.m的源代码如下：

//  CMCaptureViewController.h
//  二维码扫描

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@class CMCaptureViewController;
@protocol CMCaptureViewDelegate <NSObject>

- (void)captureController:(CMCaptureViewController *)controller data:(id)metadata;

@end

@interface CMCaptureViewController : UIViewController<AVCaptureMetadataOutputObjectsDelegate>
{
    int num;
    BOOL upOrdown;
    NSTimer * timer;
}
@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;
@property (nonatomic, retain) UIImageView * line;
@property (nonatomic, weak) id <CMCaptureViewDelegate> delegate;

@end

//  CMCaptureViewController.m
//  二维码扫描


#import "CMCaptureViewController.h"

@interface CMCaptureViewController ()

@end

@implementation CMCaptureViewController

- (void)loadView
{
    [super loadView];
    self.view.backgroundColor = [UIColor redColor];
    UIButton * scanButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [scanButton setTitle:@"取消" forState:UIControlStateNormal];
    scanButton.frame = CGRectMake(100, 420, 120, 40);
    [scanButton addTarget:self action:@selector(backAction) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:scanButton];
    
    UILabel * labIntroudction= [[UILabel alloc] initWithFrame:CGRectMake(15, 40, 290, 50)];
    labIntroudction.backgroundColor = [UIColor clearColor];
    labIntroudction.numberOfLines=2;
    labIntroudction.textColor=[UIColor whiteColor];
    labIntroudction.text=@"将二维码图像置于矩形方框内，离手机摄像头10CM左右，系统会自动识别。";
    [self.view addSubview:labIntroudction];
    
    
    UIImageView * imageView = [[UIImageView alloc]initWithFrame:CGRectMake(10, 100, 300, 300)];
    imageView.image = [UIImage imageNamed:@"pick_bg"];
    [self.view addSubview:imageView];
    
    upOrdown = NO;
    num =0;
    _line = [[UIImageView alloc] initWithFrame:CGRectMake(50, 110, 220, 2)];
    _line.image = [UIImage imageNamed:@"line.png"];
    [self.view addSubview:_line];
    
    timer = [NSTimer scheduledTimerWithTimeInterval:.02 target:self selector:@selector(animation1) userInfo:nil repeats:YES];

}


-(void)animation1
{
    if (upOrdown == NO) {
        num ++;
        _line.frame = CGRectMake(50, 110+2*num, 220, 2);
        if (2*num == 280) {
            upOrdown = YES;
        }
    }
    else {
        num --;
        _line.frame = CGRectMake(50, 110+2*num, 220, 2);
        if (num == 0) {
            upOrdown = NO;
        }
    }

}

-(void)backAction
{
    
    [self dismissViewControllerAnimated:YES completion:^{
        [timer invalidate];
    }];
}



-(void)viewWillAppear:(BOOL)animated
{
    [self setupCamera];
}
- (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;
    
    if ([metadataObjects count] >0)
    {
        AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjects objectAtIndex:0];
        stringValue = metadataObject.stringValue;
        NSLog(@"[%@]", stringValue);
    }
    
    [_session stopRunning];

    [self dismissViewControllerAnimated:YES completion:^
    {
        [timer invalidate];
        
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
            if ([self.delegate respondsToSelector:@selector(captureController:data:)])
            {
                [self.delegate captureController:self data:stringValue];
            }
        });

    }];
}

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



@end

pick_bg@2x.png

line@2x.png