標籤：
實現過程如下：
Step1:需要匯入：AVFoundation Framework 包含標頭檔：
#import <AVFoundation/AVFoundation.h>
Step2:設定捕獲會話
設定 AVCaptureSession 和 AVCaptureVideoPreviewLayer 成員
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#import <AVFoundation/AVFoundation.h> static const char *kScanQRCodeQueueName = "ScanQRCodeQueue"; @interface ViewController () <AVCaptureMetadataOutputObjectsDelegate> ..... @property (nonatomic) AVCaptureSession *captureSession; @property (nonatomic) AVCaptureVideoPreviewLayer *videoPreviewLayer; @property (nonatomic) BOOL lastResult; @end
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Step3:建立會話，讀取輸入資料流
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- (BOOL)startReading { // 擷取 AVCaptureDevice 執行個體 NSError * error; AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo]; // 初始化輸入資料流 AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error]; if (!input) { NSLog(@"%@", [error localizedDescription]); return NO; } // 建立會話 _captureSession = [[AVCaptureSession alloc] init]; // 添加輸入資料流 [_captureSession addInput:input]; // 初始化輸出資料流 AVCaptureMetadataOutput *captureMetadataOutput = [[AVCaptureMetadataOutput alloc] init]; // 添加輸出資料流 [_captureSession addOutput:captureMetadataOutput]; // 建立dispatch queue. dispatch_queue_t dispatchQueue; dispatchQueue = dispatch_queue_create(kScanQRCodeQueueName, NULL); [captureMetadataOutput setMetadataObjectsDelegate:self queue:dispatchQueue]; // 設定中繼資料類型 AVMetadataObjectTypeQRCode [captureMetadataOutput setMetadataObjectTypes:[NSArray arrayWithObject:AVMetadataObjectTypeQRCode]]; // 建立輸出對象 _videoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:_captureSession]; [_videoPreviewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill]; [_videoPreviewLayer setFrame:_sanFrameView.layer.bounds]; [_sanFrameView.layer addSublayer:_videoPreviewLayer]; // 開始會話 [_captureSession startRunning]; return YES; }
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Step4:停止讀取
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- (void)stopReading { // 停止會話 [_captureSession stopRunning]; _captureSession = nil; }
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Step5:擷取捕獲資料
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-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{ if (metadataObjects != nil && [metadataObjects count] > 0) { AVMetadataMachineReadableCodeObject *metadataObj = [metadataObjects objectAtIndex:0]; NSString *result; if ([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode]) { result = metadataObj.stringValue; } else { NSLog(@"不是二維碼"); } [self performSelectorOnMainThread:@selector(reportScanResult:) withObject:result waitUntilDone:NO]; }}
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Step6:處理結果
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- (void)reportScanResult:(NSString *)result { [self stopReading]; if (!_lastResult) { return; } _lastResut = NO; UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"二維碼掃描" message:result delegate:nil cancelButtonTitle:@"取消" otherButtonTitles: nil]; [alert show]; // 以下處理了結果，繼續下次掃描 _lastResult = YES; }
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以上基本就是二維碼的擷取流程
iOS使用AVFoundation實現二維碼掃描
