一、iOS7之后，我们可以使用系统框架来生成二维码
1、系统二维码主要通过CIFilter的对象来生成, 先导入这个类所在的框架:
#import <CoreImage/CoreImage.h>
2、生成二维码的UIImage
+ (UIImage*)createQRWithString:(NSString*)text QRSize:(CGSize)size QRColor:(UIColor*)qrColor bkColor:(UIColor*)bkColor
{
NSData *stringData = [text dataUsingEncoding: NSUTF8StringEncoding];
//生成
CIFilter *qrFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
[qrFilter setValue:stringData forKey:@"inputMessage"];
[qrFilter setValue:@"H" forKey:@"inputCorrectionLevel"];
//上色
CIFilter *colorFilter = [CIFilter filterWithName:@"CIFalseColor"
keysAndValues:
@"inputImage",qrFilter.outputImage,
@"inputColor0",[CIColor colorWithCGColor:qrColor.CGColor],
@"inputColor1",[CIColor colorWithCGColor:bkColor.CGColor],
nil];
//生成CIImage
CIImage *qrImage = colorFilter.outputImage;
//绘制
CGImageRef cgImage = [[CIContext contextWithOptions:nil] createCGImage:qrImage fromRect:qrImage.extent];
UIGraphicsBeginImageContext(size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetInterpolationQuality(context, kCGInterpolationNone);
CGContextScaleCTM(context, 1.0, -1.0);
CGContextDrawImage(context, CGContextGetClipBoundingBox(context), cgImage);
UIImage *codeImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
CGImageRelease(cgImage);
return codeImage;
}
二、在二维码上添加其他图片
1、在二维码上添加其他图片时，不能太大，否则会导致扫描不到二维码中的信息
