iOS模仿微信长按识别二维码的多种方式
参考：https://github.com/nglszs/BCQRcode
方式一：
#import <UIKit/UIKit.h>
@interface ViewController : UIViewController
@end
**************
#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.title = @"二维码";
UIBarButtonItem *leftBtn = [[UIBarButtonItem alloc]
initWithTitle:@"生成"
style:UIBarButtonItemStylePlain
target:self
action:@selector(backView)];
self.navigationItem.leftBarButtonItem = leftBtn;
UIBarButtonItem *rightBtn = [[UIBarButtonItem alloc]
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 = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(readCode:)];
[self.view addGestureRecognizer: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.layer renderInContext:context];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
//识别二维码
CIImage *ciImage = [[CIImage alloc] initWithCGImage:image.CGImage options:nil];
CIContext *ciContext = [CIContext contextWithOptions:@{kCIContextUseSoftwareRenderer : @(YES)}]; // 软件渲染
CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeQRCode context:ciContext options:@{CIDetectorAccuracy : CIDetectorAccuracyHigh}];// 二维码识别
NSArray *features = [detector featuresInImage:ciImage];
for (CIQRCodeFeature *feature in features) {
NSLog(@"msg = %@",feature.messageString); // 打印二维码中的信息
//对结果进行处理
ResultViewController *resultVC = [[ResultViewController alloc] init];
resultVC.contentString = feature.messageString;
[self.navigationController pushViewController:resultVC animated:NO];
}
}
}
- (void)backView {
UIImageView *codeImageView = [[UIImageView alloc] initWithFrame:CGRectMake((BCWidth - 200)/2, 100, 200, 200)];
codeImageView.layer.borderColor = [UIColor orangeColor].CGColor;
codeImageView.layer.borderWidth = 1;
[self.view addSubview:codeImageView];
//有图片的时候，也可以不设置圆角
[codeImageView creatCode:@"https://www.baidu.com" Image:[UIImage imageNamed:@"bg"] andImageCorner:4];
//没有图片的时候
// [codeImageView creatCode:@"这波可以" Image:nil andImageCorner:4];
}
- (void)ScanView {
[self.navigationController pushViewController:[ScanCodeViewController new] animated:YES];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// 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 = [CIFilter filterWithName:@"CIQRCodeGenerator"];
//每次调用都恢复其默认属性
[codeFilter setDefaults];
NSData *codeData = [codeContent dataUsingEncoding:NSUTF8StringEncoding];
//设置滤镜数据
[codeFilter setValue:codeData forKey:@"inputMessage"];
//获得滤镜输出的图片
CIImage *outputImage = [codeFilter outputImage];
//这里的图像必须经过位图转换，不然会很模糊
UIImage *translateImage = [self creatUIImageFromCIImage:outputImage andSize:ImageSize];
//这里如果不想设置圆角，直接传一个image就好了
UIImage *resultImage = [self setSuperImage:translateImage andSubImage:[self imageCornerRadius:imageCorner andImage: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 = [CIContext contextWithOptions:nil];
CGImageRef imageRef = [context createCGImage:image fromRect:extent];
CGContextSetInterpolationQuality(contextRef, kCGInterpolationNone);
CGContextScaleCTM(contextRef, scale, scale);
CGContextDrawImage(contextRef, extent, imageRef);
CGImageRef newImage = CGBitmapContextCreateImage(contextRef);
CGContextRelease(contextRef);
CGImageRelease(imageRef);
return [UIImage imageWithCGImage: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);
[[UIBezierPath bezierPathWithRoundedRect:frame cornerRadius: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 {
[super viewDidLoad];
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0) {
AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
if (authStatus == AVAuthorizationStatusDenied || authStatus == AVAuthorizationStatusRestricted)
{
[[[UIAlertView alloc] initWithTitle:nil message:@"本应用无访问相机的权限，如需访问，可在设置中修改" delegate:nil cancelButtonTitle:@"好的" otherButtonTitles:nil, nil] show];
return;
} else {
//打开相机
AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
//创建输入流
AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
//创建输出流
output = [[AVCaptureMetadataOutput alloc]init];
//设置代理 在主线程里刷新
[output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
//设置扫描区域，这个需要仔细调整
[output setRectOfInterest:CGRectMake(64/BCHeight, (BCWidth - 320)/2/BCWidth, 320/BCHeight, 320/BCWidth)];
//初始化链接对象
session = [[AVCaptureSession alloc]init];
//高质量采集率
[session setSessionPreset:AVCaptureSessionPresetHigh];
[session addInput:input];
[session addOutput:output];
//设置扫码支持的编码格式
output.metadataObjectTypes=@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code];
AVCaptureVideoPreviewLayer * layer = [AVCaptureVideoPreviewLayer layerWithSession:session];
layer.videoGravity=AVLayerVideoGravityResizeAspectFill;
layer.frame=self.view.layer.bounds;
[self.view.layer addSublayer: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 = [[UIImageView alloc] initWithFrame:CGRectMake(0, 64, BCWidth, BCHeight - 64)];
_backImageView.image = [UIImage imageNamed:@"camera_bg"];
[self.view addSubview:_backImageView];
_lineImageView = [[UIImageView alloc] initWithFrame:CGRectMake(16, 15, BCWidth - 32, 1)];
_lineImageView.backgroundColor = [UIColor orangeColor];
[_backImageView addSubview:_lineImageView];
//各种参数设置
lineNum = 0;
upOrDown = NO;
lineTimer = [NSTimer scheduledTimerWithTimeInterval:0.01 target:self selector:@selector(lineAnimation) userInfo:nil repeats: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 ([metadataObjects count] > 0) {
[session stopRunning]; //停止扫码
AVMetadataMachineReadableCodeObject *metadataObject = [metadataObjects firstObject];
ResultViewController *resultVC = [[ResultViewController alloc] init];
resultVC.contentString = metadataObject.stringValue;
[self.navigationController pushViewController:resultVC animated:NO];
}
}
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[session startRunning];
[lineTimer setFireDate:[NSDate distantPast]];
}
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
[session stopRunning];
[lineTimer setFireDate:[NSDate distantFuture]];
if (![self.navigationController.viewControllers containsObject:self]) {//释放timer
[lineTimer invalidate];
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 {
[super viewDidLoad];
//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 ([_contentString hasPrefix:@"http"]) {
WKWebView *showView = [[WKWebView alloc] initWithFrame:BCScreen];
NSURLRequest *codeRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:_contentString]];
[showView loadRequest:codeRequest];
[self.view addSubview:showView];
} else {
UILabel *showLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 80, 200, 50)];
showLabel.center = self.view.center;
showLabel.font = [UIFont boldSystemFontOfSize:16];
showLabel.text = [NSString stringWithFormat:@"扫描结果是---%@",_contentString];
showLabel.numberOfLines = 0;
[self.view addSubview: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
{
return YES;
}
以上所述是小编给大家介绍的iOS模仿微信长按识别二维码的多种方式，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对海外IDC网网站的支持！
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