二维码生成

#import "QRCodeGenerator.h"
@interface ViewController ()
{
   
    UITextField*field;
   
    UIButton*btn;
   
    UIImageView*imgVV;
   
}
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.view.backgroundColor = [UIColor whiteColor];
    field = [[UITextField alloc]initWithFrame:CGRectMake((self.view.frame.size.width-200)/2,100,200,44)];
    field.placeholder = @"请输入内容";
    field.borderStyle = UITextBorderStyleRoundedRect;
    [self.view addSubview:field];
        btn= [[UIButton alloc]initWithFrame:CGRectMake((self.view.frame.size.width-200)/2,180,200,44)];
        [btn setTitle:@"点击生成二维码" forState:UIControlStateNormal];
        btn.backgroundColor = [UIColor lightGrayColor];
        [btn addTarget:self action:@selector(abc) forControlEvents:UIControlEventTouchUpInside];
        [self.view addSubview:btn];
}
-(void)abc{
        imgVV= [[UIImageView alloc]initWithFrame:CGRectMake((self.view.frame.size.width-200)/2,300,200,200)];
        imgVV.image = [QRCodeGenerator qrImageForString:field.text imageSize:imgVV.bounds.size.width];
        [self.view addSubview:imgVV];



}