快速生成二維碼

導入CoreImage框架 #import <CoreImage/CoreImage.h> 
經過濾鏡CIFilter生成二維碼

#import "ViewController.h"

#import <CoreImage/CoreImage.h>

@interface ViewController ()

@property (weak, nonatomic) IBOutlet UIImageView *iv;

@end

@implementation ViewController

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

// 1.實例化二維碼濾鏡

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

// 2.恢復濾鏡的默認屬性 (由於濾鏡有可能保存上一次的屬性)

[filter setDefaults];

// 3.將字符串轉換成NSdata

NSData *data  = [@"http://www.itheima.com" dataUsingEncoding:NSUTF8StringEncoding];

// 4.經過KVO設置濾鏡, 傳入data, 未來濾鏡就知道要經過傳入的數據生成二維碼

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

// 5.生成二維碼

CIImage *outputImage = [filter outputImage];

UIImage *image = [UIImage  imageWithCIImage:outputImage];

// 6.設置生成好得二維碼到imageview上

self.iv.image = image;

}

@end