iOS开发 二维码的生成

废话不多说  代码说话

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这里的self.url直接更换为 你要生成二维码的url即可

- (void)setUpQrCodeImage{

// 1. 实例化二维码滤镜

CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];

// 2. 恢复滤镜的默认属性

[filter setDefaults];

// 3. 将字符串转换成NSData

NSString *urlStr = self.url;// 分享的二维码

NSData *data = [urlStr dataUsingEncoding:NSUTF8StringEncoding];

// 4. 通过KVO设置滤镜inputMessage数据

[filter setValue:data forKey:@"inputMessage"];

// 5. 获得滤镜输出的图像

CIImage *outputImage = [filter outputImage];

// 6. 将CIImage转换成UIImage，并放大显示 (此时获取到的二维码比较模糊,所以需要用下面的createNonInterpolatedUIImageFormCIImage方法重绘二维码)

//    UIImage *codeImage = [UIImage imageWithCIImage:outputImage scale:1.0 orientation:UIImageOrientationUp];

self.QrCodeImageView.image = [self createNonInterpolatedUIImageFormCIImage:outputImage withSize:200];//重绘二维码,使其显示清晰

}

/**

* 根据CIImage生成指定大小的UIImage

*

* @param image CIImage

* @param size 图片宽度

*/

- (UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size

{

CGRect extent = CGRectIntegral(image.extent);

CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));

// 1.创建bitmap;

size_t width = CGRectGetWidth(extent) * scale;

size_t height = CGRectGetHeight(extent) * scale;

CGColorSpaceRef cs = CGColorSpaceCreateDeviceGray();

CGContextRef bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, (CGBitmapInfo)kCGImageAlphaNone);

CIContext *context = [CIContext contextWithOptions:nil];

CGImageRef bitmapImage = [context createCGImage:image fromRect:extent];

CGContextSetInterpolationQuality(bitmapRef, kCGInterpolationNone);

CGContextScaleCTM(bitmapRef, scale, scale);

CGContextDrawImage(bitmapRef, extent, bitmapImage);

// 2.保存bitmap到图片

CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);

CGContextRelease(bitmapRef);

CGImageRelease(bitmapImage);

return [UIImage imageWithCGImage:scaledImage];

}