二维码(生成)

二维码

• 从iOS7开始集成了二维码的生成和读取功能

• 此前被广泛使用的zbarsdk目前不支持64位处理器

• 生成二维码的步骤：1>导入CoreImage框架 2>通过滤镜CIFilter生成二维码

• 二维码的内容(传统的条形码只能放数字)：1>纯文本 2>名片 3>URL

• 二维码中间的图片自己放一个UIView

//
//  ViewController.m
//  二维码
//
//  Created by ma c on 16/5/11.
//  Copyright © 2016年 YYN. All rights reserved.
//

#import "ViewController.h"
#import <CoreImage/CoreImage.h>

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIImageView *imageView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    
    CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
    
    [filter setDefaults];
    
    NSString *string = @"www.baidu.com";
    NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
    
    [filter setValue:data forKey:@"inputMessage"];
    
    CIImage *outputImage = [filter outputImage];
    
    
    self.imageView.image = [self createNonInterpolatedUIImageFormCIImage:outputImage withSize:200];

}
/**
 *  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];
}


- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end