生成二維碼

//創(chuàng)建濾鏡
    CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
    
    
    //設置屬性為默認值
    [filter setDefaults];
    
    //設置內(nèi)容
    [filter setValue:[@"https://itunes.apple.com/cn/app/招商全能王/id1153952115?mt=8" dataUsingEncoding:NSUTF8StringEncoding] forKey:@"inputMessage"];
    
    
    CIImage *image =  [filter outputImage];
    
    image = [image imageByApplyingTransform:CGAffineTransformMakeScale(8, 8)];

    這個image是保存不到相冊的，需要繪制一下

繪制圖片和保存到相冊中

    UIImage *newImage = [UIImage imageWithCIImage:image];
    
    UIGraphicsBeginImageContext(newImage.size);
    //  繪制二維碼圖片
    [newImage drawInRect:CGRectMake(0, 0, newImage.size.width, newImage.size.height)];
    
    //  從圖片上下文中取出圖片
    newImage  = UIGraphicsGetImageFromCurrentImageContext();
    
    //  關(guān)閉圖片上下文
    UIGraphicsEndImageContext();
    //保存圖片到相冊
    UIImageWriteToSavedPhotosAlbum(newImage, nil, nil, NULL);