iOS自带扫描 和 生成二维码

1.二维码生成libqrencode介绍：是一个用C语言编写的用来解析二维条形码(QRCode)的程序库，libqrencode通过手机的CCD摄像头来扫描二维条形码。导入libqrencode库，下面直接代码：[objc] view plaincopy#import < ...

1.二维码生成

libqrencode介绍：是一个用C语言编写的用来解析二维条形码(QRCode)的程序库，libqrencode通过手机的CCD摄像头来扫描二维条形码。

导入libqrencode库，下面直接代码：

 #import <Foundation/Foundation.h>

 @interface QRCodeGenerator : NSObject

 + (UIImage *)qrImageForString:(NSString *)string imageSize:(CGFloat)size;
 + (UIImage *) twoDimensionCodeImage:(UIImage *)twoDimensionCode withAvatarImage:(UIImage *)avatarImage;
 @end

 #import "QRCodeGenerator.h"
 #import "qrencode.h"

 enum {
     qr_margin = 3
 };

 @implementation QRCodeGenerator

 + (void)drawQRCode:(QRcode *)code context:(CGContextRef)ctx size:(CGFloat)size {
     unsigned charchar *data = 0;
     int width;
     data = code->data;
     width = code->width;
     float zoom = (double)size / (code->width + 2.0 * qr_margin);
     CGRect rectDraw = CGRectMake(0, 0, zoom, zoom);

     // draw
     CGContextSetFillColor(ctx, CGColorGetComponents([UIColor blackColor].CGColor));
     for(int i = 0; i < width; ++i) {
         for(int j = 0; j < width; ++j) {
             if(*data & 1) {
                 rectDraw.origin = CGPointMake((j + qr_margin) * zoom,(i + qr_margin) * zoom);
                 CGContextAddRect(ctx, rectDraw);
             }
             ++data;
         }
     }
     CGContextFillPath(ctx);
 }

 + (UIImage *)qrImageForString:(NSString *)string imageSize:(CGFloat)size {
     if (![string length]) {
         return nil;
     }

     QRcode *code = QRcode_encodeString([string UTF8String], 0, QR_ECLEVEL_L, QR_MODE_8, 1);
     if (!code) {
         return nil;
     }

     // create context
     CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
     CGContextRef ctx = CGBitmapContextCreate(0, size, size, 8, size * 4, colorSpace, kCGImageAlphaPremultipliedLast);

     CGAffineTransform translateTransform = CGAffineTransformMakeTranslation(0, -size);
     CGAffineTransform scaleTransform = CGAffineTransformMakeScale(1, -1);
     CGContextConcatCTM(ctx, CGAffineTransformConcat(translateTransform, scaleTransform));

     // draw QR on this context
     [QRCodeGenerator drawQRCode:code context:ctx size:size];

     // get image
     CGImageRef qrCGImage = CGBitmapContextCreateImage(ctx);
     UIImage * qrImage = [UIImage imageWithCGImage:qrCGImage];

     // some releases
     CGContextRelease(ctx);
     CGImageRelease(qrCGImage);
     CGColorSpaceRelease(colorSpace);
     QRcode_free(code);

     return qrImage;
 }

 + (UIImage *) twoDimensionCodeImage:(UIImage *)twoDimensionCode withAvatarImage:(UIImage *)avatarImage{

     // two-dimension code 二维码

     CGSize size = twoDimensionCode.size;

     CGSize size2 =CGSizeMake(1.0 / 5.5 * size.width, 1.0 / 5.5 * size.height);



     UIGraphicsBeginImageContext(size);



     [twoDimensionCode drawInRect:CGRectMake(0, 0, size.width, size.height)];

     [[self avatarImage:avatarImage] drawInRect:CGRectMake((size.width - size2.width) / 2.0, (size.height - size2.height) / 2.0, size2.width, size2.height)];



     UIImage *resultingImage =UIGraphicsGetImageFromCurrentImageContext();

     UIGraphicsEndImageContext();

     return resultingImage;

 }


 + (UIImage *) avatarImage:(UIImage *)avatarImage{

     UIImage * avatarBackgroudImage = [UIImage imageNamed:@"icon.png"];

     CGSize size = avatarBackgroudImage.size;

     UIGraphicsBeginImageContext(size);



     [avatarBackgroudImage drawInRect:CGRectMake(0, 0, size.width, size.height)];

     [avatarImage drawInRect:CGRectMake(10, 10, size.width - 20, size.height - 20)];



     UIImage *resultingImage =UIGraphicsGetImageFromCurrentImageContext();

     UIGraphicsEndImageContext();

     return resultingImage;

 }

 @end

2.扫描

iOS7苹果推出了自带的扫描功能，下面直接代码：

 -(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 =@[AVMetadataObjectTypeCode128Code,AVMetadataObjectTypeUPCECode,AVMetadataObjectTypeCode39Code,AVMetadataObjectTypeCode39Mod43Code,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeCode93Code,AVMetadataObjectTypePDF417Code,AVMetadataObjectTypeQRCode,AVMetadataObjectTypeAztecCode,AVMetadataObjectTypeInterleaved2of5Code,AVMetadataObjectTypeITF14Code,AVMetadataObjectTypeDataMatrixCode] ;

     // 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;
     }

     [_session stopRunning];
     UIAlertView * alert = [[UIAlertView alloc]initWithTitle:@"提示" message:[NSString stringWithFormat:@"结果：%@",stringValue] delegate:self cancelButtonTitle:nil otherButtonTitles:@"知道了",@"重新扫描", nil nil];
     [alert show];
 }
 - (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
 {
     if(buttonIndex == 0)
     {
         [self dismissViewControllerAnimated:YES completion:^
          {
              [timer invalidate];
          }];

     }
     else
     {
         [_session startRunning];
     }
 }