ios开发 根据URL或字符串生成二维码

1.二话不说直接上代码

//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.dataDic[@"shareurl"];
NSData *data = [urlStr dataUsingEncoding:NSUTF8StringEncoding];
// 4. 经过KVO设置滤镜inputMessage数据
[filter setValue:data forKey:@"inputMessage"];
// 5. 得到滤镜输出的图像
CIImage *outputImage = [filter outputImage];
// 6. 将CIImage转换成UIImage，并显示于imageView上 (此时获取到的二维码比较模糊,因此须要用下面的createNonInterpolatedUIImageFormCIImage方法重绘二维码)
self.QRcodeContentImageView = [[UIImageView alloc] initWithFrame:CGRectMake((SCREEN_WIDTH-170)/2, CGRectGetMaxY(nameLabel.frame) + 10, 170, 170)];
self.QRcodeContentImageView.image = [self createNonInterpolatedUIImageFormCIImage:outputImage withSize:170];//重绘二维码,使其显示清晰
[self.view addSubview:self.QRcodeContentImageView];

2.重绘方法

/** * 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.建立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];
}

注：本文转载于其余博客，github地址:https://github.com/ZSyingyu/ZYYCodePayDemo.git