使用二维码——第三方库ZBar和libqrencode的使用

1.下载ZBar SDK并导入工程
地址：https://github.com/bmorton/ZBarSDK
2.往项目中添加Framework框架及动态库

AVFoundation.framework
CoreMedia.framework
CoreVideo.framework
libiconv.dylib
libber.a

3.在使用的地方引入头文件

#import "ZBarSDK.h"

4.使用 ZBarReaderViewController扫描二维码

扫描：
- (void)scan:(id)sender{    
ZBarReaderViewController *reader = [[ZBarReaderViewController alloc] init];   
reader.readerDelegate = self;    reader.supportedOrientationsMask = ZBarOrientationMaskAll;    
ZBarImageScanner *scanner = reader.scanner;    [scanner setSymbology:ZBAR_I25 config:ZBAR_CFG_ENABLE to:0];       
reader.showsZBarControls = YES;       [self presentViewController:reader animated:YES completion:nil];
}

现在获取二维码的相关信息：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo(NSDictionary *)info{    
idresults = [info objectForKey:ZBarReaderControllerResults];    
ZBarSymbol *symbol = nil;    //代码如何修改   
 for (symbol in results)        break;    //symbol = results;   
 imageVIew.image = [info objectForKey:UIImagePickerControllerOriginalImage];   
    [picker dismissViewControllerAnimated:YES completion:nil];
    _label.text = symbol.data;   
    NSLog(@"扫描内容:%@",symbol.data);
}

5.使用 ZBarReaderView实现扫描页面高度订制
实现协议 ZBarReaderViewDelegate （UIAlertView）
并定义： ZBarReaderView *readerVIew;
ZBarCameraSimulator *cameraSim;

实现代码：
readerVIew = [[ZBarReaderView alloc]init];    readerVIew.frame = CGRectMake(50, 44, 200, 200);    readerVIew.readerDelegate = self;    //关闭闪光灯    readerVIew.torchMode = 0;    //扫描区域：很重要    CGRect scanMaskRect = CGRectMake(60, CGRectGetMidY(readerVIew.frame)-126, 200, 200);       //[readerVIew setAllowsPinchZoom:YES];       if (TARGET_IPHONE_SIMULATOR)//应为是否有权限？    {        cameraSim = [[ZBarCameraSimulator alloc]initWithViewController:self];        cameraSim.readerView = readerVIew;    }    [self.view addSubview:readerVIew];    //扫描区域计算:加上该代码后似乎无法扫描出结果了    readerVIew.scanCrop = [self getScanCrop:scanMaskRect readerViewBounds:readerVIew.bounds];    [readerVIew start];

区域范围：

-(CGRect)getScanCrop:(CGRect)rect readerViewBounds:(CGRect)readerViewBounds{    CGFloat x,y,width,height;       x = rect.origin.x / readerViewBounds.size.width;    y = rect.origin.y / readerViewBounds.size.height;    width = rect.size.width / readerViewBounds.size.width;    height = rect.size.height / readerViewBounds.size.height;       return CGRectMake(x, y, width, height);
}

ZBarReaderViewDelegate的方法：

- (void)readerView:(ZBarReaderView *)readerView didReadSymbols:(ZBarSymbolSet *)symbols fromImage:(UIImage *)image{    NSString *codeData = [[NSString alloc]init];    for (ZBarSymbol *sym in symbols)    {        codeData = sym.data;        break;    }    //可以获取到    UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"扫描结果" message:codeData delegate:self cancelButtonTitle:@"OK" otherButtonTitles: nil];    alert.delegate = self;    [alert show];    [readerVIew stop];
}

打开获取到的信息：

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{       [[UIApplication sharedApplication]openURL:[NSURL URLWithString:alertView.message]];
}

6.使用libqrencode生成二维码
步骤一：首先向工程中导入第三方库libqrencode
步骤二：向QRCodeGenerator.h或者整个项目中引入框架 #import ，否则会报错
步骤三：在相应的文件中引入头文件

#import "QRCodeGenerator.h"

步骤四：调用库中的方法生成图片（参数为字符串和图片大小）

        UIImage *image = [QRCodeGenerator qrImageForString:_label.text imageSize:imageVIew.bounds.size.width];

其他应用待进一步挖掘。