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iOS之长按识别二维码/生成二维码/扫描二维码

2017-07-21 15:03 363 查看
参考:http://www.jianshu.com/p/997cec333822

参考:https://github.com/nglszs/BCQRcode

方式一:长按识别二维码

#import <UIKit/UIKit.h>

@interface ViewController :
UIViewController

@end

**************

#import "ViewController.h"

@interface
ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {

    [superviewDidLoad];

    

    self.title =@"二维码";

    

    UIBarButtonItem *leftBtn = [[UIBarButtonItemalloc]

                                initWithTitle:@"生成"

                                style:UIBarButtonItemStylePlain

                                target:self

                                action:@selector(backView)];

    self.navigationItem.leftBarButtonItem = leftBtn;

    UIBarButtonItem *rightBtn = [[UIBarButtonItemalloc]

                                 initWithTitle:@"扫描"

                                 style:UIBarButtonItemStylePlain

                                 target:self

                                 action:@selector(ScanView)];

    self.navigationItem.rightBarButtonItem =
rightBtn;

   //长按识别图中的二维码,类似于微信里面的功能,前提是当前页面必须有二维码

    UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizeralloc]initWithTarget:selfaction:@selector(readCode:)];

    [self.viewaddGestureRecognizer:longPress];

    

  

}

- (void)readCode:(UILongPressGestureRecognizer *)pressSender {

    if (pressSender.state ==UIGestureRecognizerStateBegan)
{

        

        

        //截图再读取

        UIGraphicsBeginImageContextWithOptions(self.view.bounds.size,YES,
0);

        

        CGContextRef context =UIGraphicsGetCurrentContext();

        

        [self.view.layerrenderInContext:context];

        

        UIImage *image =UIGraphicsGetImageFromCurrentImageContext();

        UIGraphicsEndImageContext();

        

        

     //识别二维码 

        CIImage *ciImage = [[CIImagealloc]initWithCGImage:image.CGImageoptions:nil];

        CIContext *ciContext = [CIContextcontextWithOptions:@{kCIContextUseSoftwareRenderer
: @(YES)}];//软件渲染

       

        CIDetector *detector = [CIDetectordetectorOfType:CIDetectorTypeQRCodecontext:ciContextoptions:@{CIDetectorAccuracy
:CIDetectorAccuracyHigh}];//二维码识别

        

        

        NSArray *features = [detectorfeaturesInImage:ciImage];

        

        

        for (CIQRCodeFeature *featurein features) {

           

            

            NSLog(@"msg = %@",feature.messageString);//打印二维码中的信息

            

            //对结果进行处理

            ResultViewController *resultVC = [[ResultViewControlleralloc]init];

            resultVC.contentString = feature.messageString;

            [self.navigationControllerpushViewController:resultVCanimated:NO];

        }

        

    }

}

- (void)backView {

    

  

    

        

        UIImageView *codeImageView = [[UIImageViewalloc]initWithFrame:CGRectMake((BCWidth
- 200)/2, 100, 200, 200)];

        codeImageView.layer.borderColor = [UIColororangeColor].CGColor;

        codeImageView.layer.borderWidth = 1;

        [self.viewaddSubview:codeImageView];

        

       

   
//有图片的时候,也可以不设置圆角

    [codeImageView creatCode:@"https://www.baidu.com"Image:[UIImageimageNamed:@"bg"]andImageCorner:4];

    

   
//没有图片的时候

    //  [codeImageView creatCode:@"这波可以" Image:nil andImageCorner:4];

}

- (void)ScanView {

    

    [self.navigationControllerpushViewController:[ScanCodeViewControllernew]animated:YES];

}

- (void)didReceiveMemoryWarning {

    [superdidReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

@end

************生成二维码

#import <UIKit/UIKit.h>

@interface UIImageView (CreatCode)

/**

 这里传入二维码的信息,image是加载二维码上方的图片,如果不要图片直接codeImage为nil即可,后面是图片的圆角

 */

- (void)creatCode:(NSString *)codeContent Image:(UIImage *)codeImage andImageCorner:(CGFloat)imageCorner;

@end
**************

#import "UIImageView+CreatCode.h"

#define ImageSize self.bounds.size.width

@implementation UIImageView (CreatCode)

- (void)creatCode:(NSString *)codeContent Image:(UIImage *)codeImage andImageCorner:(CGFloat)imageCorner
{

    

   
//用CoreImage框架实现二维码的生成,下面方法最好异步调用

    

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,
0), ^{

        CIFilter *codeFilter = [CIFilterfilterWithName:@"CIQRCodeGenerator"];

        

       
//每次调用都恢复其默认属性

        [codeFilter setDefaults];

        

        NSData *codeData = [codeContentdataUsingEncoding:NSUTF8StringEncoding];

        

        //设置滤镜数据

        [codeFilter setValue:codeDataforKey:@"inputMessage"];

        

        //获得滤镜输出的图片

        CIImage *outputImage = [codeFilteroutputImage];

        

       
//这里的图像必须经过位图转换,不然会很模糊

        

        UIImage *translateImage = [selfcreatUIImageFromCIImage:outputImageandSize:ImageSize];

        

       
//这里如果不想设置圆角,直接传一个image就好了

        UIImage *resultImage = [selfsetSuperImage:translateImageandSubImage:[selfimageCornerRadius:imageCornerandImage:codeImage]];

        

        dispatch_async(dispatch_get_main_queue(), ^{

            

            self.image = resultImage;

         

        });

       

        

        

});

}

//这里的size我是用imageview的宽度来算的,你可以改为自己想要的size

- (UIImage *)creatUIImageFromCIImage:(CIImage *)image andSize:(CGFloat)size
{

   
//下面是创建bitmao没什么好解释的,不懂得自行百度或者参考官方文档

    

    CGRect extent =CGRectIntegral(image.extent);

    CGFloat scale =MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));

    

    size_t width =CGRectGetWidth(extent) * scale;

    size_t height =CGRectGetHeight(extent) * scale;

    

    CGColorSpaceRef colorRef =CGColorSpaceCreateDeviceGray();

    

    CGContextRef contextRef =CGBitmapContextCreate(nil,
width, height, 8, 0, colorRef, (CGBitmapInfo)kCGImageAlphaNone);

    

    CIContext *context = [CIContextcontextWithOptions:nil];

    

    CGImageRef imageRef = [contextcreateCGImage:imagefromRect:extent];

    CGContextSetInterpolationQuality(contextRef,kCGInterpolationNone);

    

    CGContextScaleCTM(contextRef, scale, scale);

    

    CGContextDrawImage(contextRef, extent, imageRef);

    CGImageRef  newImage =CGBitmapContextCreateImage(contextRef);

    CGContextRelease(contextRef);

    CGImageRelease(imageRef);

    

    

    

    return [UIImageimageWithCGImage:newImage];

}

//这里将二维码上方的图片设置圆角并缩放

- (UIImage *)imageCornerRadius:(CGFloat)cornerRadius andImage:(UIImage
*)image {

   
//这里是将图片进行处理,frame不能太大,否则会挡住二维码

    CGRect frame =CGRectMake(0, 0,ImageSize/5,
ImageSize/5);

    UIGraphicsBeginImageContextWithOptions(frame.size,NO,
0);

    [[UIBezierPathbezierPathWithRoundedRect:framecornerRadius:cornerRadius]addClip];

    

    [image drawInRect:frame];

    UIImage *clipImage =UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return clipImage;

}

- (UIImage *)setSuperImage:(UIImage *)superImage andSubImage:(UIImage *)subImage
{

   
//将两张图片绘制在一起

    UIGraphicsBeginImageContextWithOptions(superImage.size,YES,
0);

    [superImage drawInRect:CGRectMake(0, 0, superImage.size.width,
superImage.size.height)];

    [subImage drawInRect:CGRectMake((ImageSize -ImageSize/5)/2,
(ImageSize -ImageSize/5)/2, subImage.size.width,
subImage.size.height)];

    UIImage *resultImage =UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    

    

    return resultImage;

}

@end

***************扫描二维码

#import <UIKit/UIKit.h>

#import <AVFoundation/AVFoundation.h>

@interface ScanCodeViewController :UIViewController<AVCaptureMetadataOutputObjectsDelegate>

{

    AVCaptureSession * session;

    AVCaptureMetadataOutput * output;

    NSInteger lineNum;

    BOOL upOrDown;

    NSTimer *lineTimer;

}

@property (nonatomic,strong)UIImageView
*lineImageView;

@property (nonatomic,strong)UIImageView
*backImageView;

@end

******************

#import "ScanCodeViewController.h"

@implementation ScanCodeViewController

- (void)viewDidLoad {

    [superviewDidLoad];

    

    

    if ([[[UIDevicecurrentDevice]systemVersion]floatValue]
>= 7.0) {

                AVAuthorizationStatus authStatus =  [AVCaptureDeviceauthorizationStatusForMediaType:AVMediaTypeVideo];

        

                if (authStatus ==AVAuthorizationStatusDenied || authStatus ==AVAuthorizationStatusRestricted)

                {

                    [[[UIAlertViewalloc]initWithTitle:nilmessage:@"本应用无访问相机的权限,如需访问,可在设置中修改"delegate:nilcancelButtonTitle:@"好的"otherButtonTitles:nil,nil]show];

                    return;

        

                } else {

        

        

                    //打开相机

                    AVCaptureDevice * device = [AVCaptureDevicedefaultDeviceWithMediaType:AVMediaTypeVideo];

                   

                    //创建输入流

                    AVCaptureDeviceInput * input = [AVCaptureDeviceInputdeviceInputWithDevice:deviceerror:nil];

                    //创建输出流

                    output = [[AVCaptureMetadataOutputalloc]init];

                    //设置代理在主线程里刷新

                    [outputsetMetadataObjectsDelegate:selfqueue:dispatch_get_main_queue()];

        

                    //设置扫描区域,这个需要仔细调整

                    [outputsetRectOfInterest:CGRectMake(64/BCHeight,
(BCWidth - 320)/2/BCWidth, 320/BCHeight, 320/BCWidth)];

        

        

                    //初始化链接对象

                    session = [[AVCaptureSessionalloc]init];

                    //高质量采集率

                    [sessionsetSessionPreset:AVCaptureSessionPresetHigh];

        

                    [sessionaddInput:input];

                    [sessionaddOutput:output];

        

                    //设置扫码支持的编码格式

                    output.metadataObjectTypes=@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeCode128Code];

        

                    

                    AVCaptureVideoPreviewLayer * layer = [AVCaptureVideoPreviewLayerlayerWithSession:session];

                    layer.videoGravity=AVLayerVideoGravityResizeAspectFill;

                    layer.frame=self.view.layer.bounds;

                    [self.view.layeraddSublayer:layer];

        

            }

    }

    

    

                [self_initView];

}

//里面所有的控件可以自己定制,这里只是简单的例子

- (void)_initView {

    //扫码框

    _backImageView = [[UIImageViewalloc]initWithFrame:CGRectMake(0,
64,BCWidth,BCHeight - 64)];

    _backImageView.image = [UIImageimageNamed:@"camera_bg"];

    [self.viewaddSubview:_backImageView];

    

    _lineImageView = [[UIImageViewalloc]initWithFrame:CGRectMake(16,
15,BCWidth - 32, 1)];

    _lineImageView.backgroundColor = [UIColororangeColor];

    [_backImageViewaddSubview:_lineImageView];

    

    //各种参数设置

    lineNum = 0;

    upOrDown =NO;

    

    lineTimer = [NSTimerscheduledTimerWithTimeInterval:0.01target:selfselector:@selector(lineAnimation)userInfo:nilrepeats:YES];

}

-(void)lineAnimation {

    if (upOrDown ==NO) {

        lineNum ++;

        _lineImageView.frame =CGRectMake(CGRectGetMinX(_lineImageView.frame),
15 + lineNum, BCWidth - 32, 1);

        CGFloat tempHeight =CGRectGetHeight(_backImageView.frame)
* 321/542;

        NSInteger height = (NSInteger)tempHeight + 20;

        if (lineNum == height) {

            upOrDown =YES;

        }

    }

    else {

        lineNum --;

        _lineImageView.frame =CGRectMake(CGRectGetMinX(_lineImageView.frame),
15 + lineNum, BCWidth - 32, 1);

        if (lineNum == 0) {

            upOrDown =NO;

        }

    }

}

#pragma mark AVCaptureMetadataOutputObjectsDelegate

- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray
*)metadataObjects fromConnection:(AVCaptureConnection *)connection {

    if ([metadataObjectscount] > 0) {

        

        [sessionstopRunning];//停止扫码

        

        

        AVMetadataMachineReadableCodeObject *metadataObject = [metadataObjectsfirstObject];

        

        ResultViewController *resultVC = [[ResultViewControlleralloc]init];

        resultVC.contentString = metadataObject.stringValue;

        [self.navigationControllerpushViewController:resultVCanimated:NO];

        

        

    }

}

- (void)viewWillAppear:(BOOL)animated {

    [superviewWillAppear:animated];

    

    [sessionstartRunning];

    [lineTimersetFireDate:[NSDatedistantPast]];

}

- (void)viewWillDisappear:(BOOL)animated {

    [superviewWillDisappear:animated];

    

    [sessionstopRunning];

    [lineTimersetFireDate:[NSDatedistantFuture]];

    

    if (![self.navigationController.viewControllers containsObject:self])
{//释放timer

        

        [lineTimerinvalidate];

        lineTimer =nil;

    }

}

- (void)dealloc {

    NSLog(@"已释放");

}

@end

*******吧识别的二维码信息传过来加载网页

#import <UIKit/UIKit.h>

@interface ResultViewController :UIViewController

@property(nonatomic,retain)NSString
*contentString;

@end

********

#import "ResultViewController.h"

#import <WebKit/WebKit.h>

@implementation ResultViewController

- (void)viewDidLoad {

    [superviewDidLoad];

    

   
//这个界面我只是简单的处理一下,可以自己定制,实际应用中扫码跳转不可能就这两种逻辑

    if ([_contentStringhasPrefix:@"http"])
{

        

        WKWebView *showView = [[WKWebViewalloc]initWithFrame:BCScreen];

        NSURLRequest *codeRequest = [NSURLRequestrequestWithURL:[NSURLURLWithString:_contentString]];

        [showView loadRequest:codeRequest];

        [self.viewaddSubview:showView];

        

    } else {

        

        UILabel *showLabel = [[UILabelalloc]initWithFrame:CGRectMake(0,
80, 200, 50)];

        showLabel.center =self.view.center;

        showLabel.font = [UIFontboldSystemFontOfSize:16];

        showLabel.text = [NSStringstringWithFormat:@"扫描结果是---%@",_contentString];

        showLabel.numberOfLines = 0;

        [self.viewaddSubview:showLabel];

    }

    

    

}

@end

方式二:识别网页中的二维码

iOS WebView中 长按二维码的识别

思路:

长按webView 的过程中 截屏,再去解析是否有二维码,但是有个缺点 就是 万一截了一个 一半的二维码 那就无解了。
在webview中 注入获取点击图片的JS 获取图片,再解析。缺点:万一图片过大 需要下载,势必会影响用户体验。

@interface CVWebViewController ()<UIGestureRecognizerDelegate>

@property (weak,nonatomic)IBOutlet UIWebView
*webView;

@end

@implementation CVWebViewController

- (void)viewDidLoad

{

    [self.webView  loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://mp.weixin.qq.com/s?__biz=MzI2ODAzODAzMw==&mid=2650057120&idx=2&sn=c875f7d03ea3823e8dcb3dc4d0cff51d&scene=0#wechat_redirect"]]];

    UILongPressGestureRecognizer *longPressed = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressed:)];

    longPressed.delegate = self;

    [self.webView addGestureRecognizer:longPressed];

}

- (void)longPressed:(UITapGestureRecognizer*)recognizer

{

    if (recognizer.state != UIGestureRecognizerStateBegan) {

        return;

    }

    CGPoint touchPoint = [recognizer locationInView:self.webView];

    NSString *js = [NSString stringWithFormat:@"document.elementFromPoint(%f, %f).src", touchPoint.x, touchPoint.y];

    NSString *imageUrl = [self.webView stringByEvaluatingJavaScriptFromString:js];

    if (imageUrl.length == 0) {

        return;

    }

    NSLog(@"image url:%@",imageUrl);

    NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:imageUrl]];

    

    UIImage *image = [UIImage imageWithData:data];

    if (image) {

        //......

        //save image or Extract QR code

    }

}

-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer

{

    returnYES;

}
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