二维码扫描

自用-二维码扫描模块代码

效果图

scan.gif

直接上代码 注释写的还算详细
-需要准备下面的东西,其中preView是要显示的样式(就是摄像头画面加一个扫描框,因为扫描是不需要画面的,为了用户体验)

@interface ScanViewController () 
 //1.输入设备(从外界采集信息)  输入设备很多种  摄像头  麦克风  键盘
@property (nonatomic, strong) AVCaptureDeviceInput* input;
//2.输出设备 (解析采集来得内容 然后获取到数据) Metadata 元数据
@property (nonatomic, strong) AVCaptureMetadataOutput* output;
//3.会话 session (连接输入和输出进行工作)
@property (nonatomic, strong) AVCaptureSession* session;//4.展示layer@property (nonatomic, strong) PreView* preView;
@end

• 接下来是扫描代码
  #pragma mark--开始扫描
  - (void)startScan
  {

      //1.输入设备(从外界采集信息)
      //创建具体的设备  摄像头
      //AVMediaTypeVideo  摄像头     AVMediaTypeAudio 麦克风
     AVCaptureDevice* device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    self.input = [AVCaptureDeviceInput deviceInputWithDevice:device error:NULL];
  
    //2.输出设备 (解析采集来得内容 然后获取到数据) Metadata 元数据
    self.output = [[AVCaptureMetadataOutput alloc] init];
  
    //3.会话 session (连接输入和输出进行工作)
  
    self.session = [[AVCaptureSession alloc] init];
  
    //会话扫描展示的大小
    [self.session setSessionPreset:AVCaptureSessionPresetHigh];
    //添加输入设备和输出设备
    if ([self.session canAddInput:self.input]) {
        [self.session addInput:self.input];
    }
    if ([self.session canAddOutput:self.output]) {
        [self.session addOutput:self.output];
    }
  
    //指定输出设备的 代理   来返回 解析到得数据
    [self.output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
  
    //设置元数据类型 QRCode 二维码+条形码
    [self.output setMetadataObjectTypes:@[ AVMetadataObjectTypeQRCode, AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code ]];
  
    //.创建特殊视图展示二维码界面
    self.preView = [[PreView alloc] initWithFrame:self.view.bounds];
    self.preView.session = self.session;
    [self.view addSubview:self.preView];
  
    //设置扫描区域(我设置的中间靠上w:300 h:300,这样不会打开就扫描上,用户体验会好点)-需要先设置frame 然后转化添加到上去
    CGRect rect = CGRectMake(30, 100, 300, 300);
    CGRect interRect = [self.preView.previewLayer metadataOutputRectOfInterestForRect:rect];
    self.output.rectOfInterest = interRect;
  
    //5.开启 会话
    [self.session startRunning];
    }
  

• 然后就是扫描到结果 从代理的实现中拿到结果
  #pragma mark--扫描成功 二维码代理--
  /**
  * 解析出元数据就会调用
  *
  * @param captureOutput 输出
  * @param metadataObjects 元数据数组
  * @param connection 连接
  /
  - (void)captureOutput(AVCaptureOutput)captureOutput didOutputMetadataObjects:(NSArray)metadataObjects fromConnection:(AVCaptureConnection)connection
  {
  //结束扫描
  [self stopScan];
  NSMutableString* str = [NSMutableString string];
  for (AVMetadataMachineReadableCodeObject* objc in metadataObjects) {
  [str appendString:objc.stringValue];
  }
  //打印
  NSLog(@"%@",(NSString *)str);
  [self.navigationController popViewControllerAnimated:YES];
  }
  -结束扫描的代码
  #pragma mark--结束扫描
  - (void)stopScan
  {
  //停止会话
  [self.session stopRunning];
  //移除特殊的图层
  [self.preView removeFromSuperview];
  }

• 接下来需要注意的就是preView的实现 向微信扫描一样,有一个半透明的遮罩,中间有一个透明区域,这个地方用layer的mask实现,扫描动画,使用定时器实现,上代码
  @interface PreView ()
  @property(nonatomic,strong)UIImageView bgImage;
  //添加线
  @property (nonatomic, strong) UIImageView lineImageView;
  //定时器
  @property (nonatomic, strong) CADisplayLink* displayLink;
  @end

  @implementation PreView
  /**
  *  layer
  *  @return 返回AVCaptureVideoPreviewLayer 特殊的layer 可以展示输入设备采集到的信息
  */
  +(Class)layerClass{
      return [AVCaptureVideoPreviewLayer class];
   }
  
  -(AVCaptureVideoPreviewLayer *)previewLayer{
  
      AVCaptureVideoPreviewLayer *layer = (AVCaptureVideoPreviewLayer *)self.layer;
      return layer;
  }
  
  -(void)setSession:(AVCaptureSession *)session{
  
      _session = session;
      AVCaptureVideoPreviewLayer *layer = (AVCaptureVideoPreviewLayer *)self.layer;
      layer.session = session;
  }
  - (instancetype)initWithFrame:(CGRect)frame
  {
      self = [super initWithFrame:frame];
      if (self) {
         [self setMask];
      }
      return self;
  }
  -(void)setMask{
     //添加扫描线
     self.lineImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"line"]];
     self.lineImageView.frame = CGRectMake((kScreenWidth - 280) / 2, 100, 280, 2);
     [self addSubview:self.lineImageView];
     //计时器
     self.displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(scanAnimation)];
    [self.displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
     //创建一个maskView
     UIView *maskView = [[UIView alloc]initWithFrame:CGRectMake(0, 64, kScreenWidth, kScreenHigh-64)];
     //颜色设置透明
      maskView.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.5];
      [self addSubview:maskView];
      //创建一个中间有镂空区域的path
      UIBezierPath *maskPath = [UIBezierPath bezierPathWithRect:CGRectMake(0, 0, kScreenWidth, kScreenHigh-64)];
      [maskPath appendPath:[[UIBezierPath bezierPathWithRoundedRect:CGRectMake((kScreenWidth-280)/2, 100-64, 280, 280) cornerRadius:1] bezierPathByReversingPath]];
  
     CAShapeLayer *maskLayer = [[CAShapeLayer alloc]init];
     maskLayer.path = maskPath.CGPath;
     maskView.layer.mask = maskLayer;
    //添加扫描框
    [self addSubview:self.bgImage];
    _bgImage.frame = CGRectMake((kScreenWidth-280)/2, 100, 280, 280);
  }
  
   #pragma mark--扫描动画--
  - (void)scanAnimation
  {
    CGRect frame = self.lineImageView.frame;
    if (self.lineImageView.frame.origin.y > 100 + 270) {
       frame.origin.y = 100;
       self.lineImageView.frame = frame;
       } else {
        frame.origin.y += 2;
        self.lineImageView.frame = frame;
               }
  }
  
   #pragma mark --懒加载
   -(UIImageView *)bgImage{ 
     if (!_bgImage) {
    _bgImage = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"icon_scanbg"]];
      }
     return _bgImage;
  }
  @end
  

• 差不多 这样就搞定了,需要注意的是preView的加载和移除 还有扫描方法的加载时间,发现如果Push出来的窗口,二维码界面打开会有一秒多延迟,建议加一个MBProgress过度,如果Model的话,就没有这个问题(执行扫描我在viewWillAppear中加载)

附上github地址:https://github.com/superHS/Demo.git