iOS系統原生二維碼條碼掃描

iOS系統原生二維碼條碼掃描

本文講述如何用系統內建的東東實現二維碼掃描的功能:點擊當前頁面的某個按鈕，建立掃描VIEW。細心的小夥伴可以發現 title被改變了，返回按鈕被隱藏了。這個代碼自己寫就行了，與本文關係不大。。。綠色的線會上下跑，不要擔心:D

實現效果如下：

　　1.在工程中添加架構AVFoundation.framework

　　2.聲明代理：AVCaptureMetadataOutputObjectsDelegate 。 define 幾個東東用來畫框、畫線：

#define SCANVIEW_EdgeTop 40.0#define SCANVIEW_EdgeLeft 50.0#define TINTCOLOR_ALPHA 0.2 //淺色透明度#define DARKCOLOR_ALPHA 0.5 //深色透明度#define VIEW_WIDTH [UIScreen mainScreen].bounds.size.width#define VIEW_HEIGHT [UIScreen mainScreen].bounds.size.height

 

　　3.聲明以下屬性：

    AVCaptureSession * session;//輸入輸出的中間橋樑    UIView *AVCapView;//此 view 用來放置掃描框、取消按鈕、說明 label    UIView *_QrCodeline;//上下移動綠色的線條    NSTimer *_timer;

　　4.在某個方法中（我是點擊掃描按鈕）建立掃描介面，開始掃描：

 //建立一個 view 來放置掃描地區、說明 label、取消按鈕    UIView *tempView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, [UIScreen mainScreen].bounds.size.height )];    AVCapView = tempView;    AVCapView.backgroundColor = [UIColor colorWithRed:54.f/255 green:53.f/255 blue:58.f/255 alpha:1];        UIButton *cancelBtn = [[UIButton alloc]initWithFrame:CGRectMake(15, [UIScreen mainScreen].bounds.size.height - 100, 50, 25)];    UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(15, 268, 290, 60)];    label.numberOfLines = 0;    label.text = @"小提示：將條碼或二維碼對準上方地區中心即可";    label.textColor = [UIColor grayColor];    [cancelBtn setTitle:@"取消" forState: UIControlStateNormal];    [cancelBtn setTitleColor:[UIColor grayColor] forState:UIControlStateNormal];    [cancelBtn addTarget:self action:@selector(touchAVCancelBtn) forControlEvents:UIControlEventTouchUpInside];    [AVCapView addSubview:label];    [AVCapView addSubview:cancelBtn];    [self.view addSubview:AVCapView];            //畫上邊框    UIView *topView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop, VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft, 1)];    topView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:topView];        //畫左邊框    UIView *leftView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop , 1,VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft )];    leftView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:leftView];        //畫右邊框    UIView *rightView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft + VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop , 1,VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + 1)];    rightView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:rightView];        //畫下邊框    UIView *downView = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop + VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft,VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft ,1 )];    downView.backgroundColor = [UIColor whiteColor];    [AVCapView addSubview:downView];        //畫中間的基準線    _QrCodeline = [[UIView alloc] initWithFrame:CGRectMake(SCANVIEW_EdgeLeft + 1, SCANVIEW_EdgeTop, VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft - 1, 2)];    _QrCodeline.backgroundColor = [UIColor greenColor];    [AVCapView addSubview:_QrCodeline];            // 先讓基準線運動一次，避免定時器的時差    [UIView animateWithDuration:1.2 animations:^{                _QrCodeline.frame = CGRectMake(SCANVIEW_EdgeLeft + 1, VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + SCANVIEW_EdgeTop , VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft - 1, 2);            }];    [self performSelector:@selector(createTimer) withObject:nil afterDelay:0.4];        AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];    //建立輸入資料流    AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];    //建立輸出資料流    AVCaptureMetadataOutput * output = [[AVCaptureMetadataOutput alloc]init];    //設定代理 在主線程裡重新整理    [output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];        //初始化連結化物件    session = [[AVCaptureSession alloc]init];    //高品質採集率    [session setSessionPreset:AVCaptureSessionPresetHigh];        [session addInput:input];    [session addOutput:output];    //設定掃碼支援的編碼格式(如下設定條碼和二維碼相容)    output.metadataObjectTypes=@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code];        AVCaptureVideoPreviewLayer * layer = [AVCaptureVideoPreviewLayer layerWithSession:session];    layer.videoGravity=AVLayerVideoGravityResizeAspectFill;    layer.frame = CGRectMake(SCANVIEW_EdgeLeft, SCANVIEW_EdgeTop, VIEW_WIDTH- 2 * SCANVIEW_EdgeLeft, 220);    [AVCapView.layer insertSublayer:layer atIndex:0];    //開始捕獲    [session startRunning];

　　5.實現定時器、還有基準線的滾動方法

- (void)createTimer{    _timer=[NSTimer scheduledTimerWithTimeInterval:1.1 target:self selector:@selector(moveUpAndDownLine) userInfo:nil repeats:YES];}- (void)stopTimer{    if ([_timer isValid] == YES) {        [_timer invalidate];        _timer = nil;    }    }// 滾來滾去 :D :D :D- (void)moveUpAndDownLine{    CGFloat YY = _QrCodeline.frame.origin.y;        if (YY != VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + SCANVIEW_EdgeTop ) {        [UIView animateWithDuration:1.2 animations:^{            _QrCodeline.frame = CGRectMake(SCANVIEW_EdgeLeft + 1, VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft + SCANVIEW_EdgeTop , VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft - 1,2);        }];    }else {        [UIView animateWithDuration:1.2 animations:^{            _QrCodeline.frame = CGRectMake(SCANVIEW_EdgeLeft + 1, SCANVIEW_EdgeTop, VIEW_WIDTH - 2 * SCANVIEW_EdgeLeft - 1,2);        }];    }}

6.掃描成功後，想幹嘛幹嘛，就在這個代理方法裡面實現就行了

-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{    if (metadataObjects.count>0) {        //[session stopRunning];        AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjects objectAtIndex : 0 ];        //輸出掃描字串        NSLog(@"%@",metadataObject.stringValue);        [session stopRunning];        [self stopTimer];        [AVCapView removeFromSuperview];        .....        }}

 

7.如果使用者不想掃描了，點擊取消按鈕：

- (void)touchAVCancelBtn{    [session stopRunning];//攝像也要停止    [self stopTimer];//定時器要停止    [AVCapView removeFromSuperview];//剛剛建立的 view 要移除       ...        }