原生二維碼掃描

個人是比較支援用原生二維碼掃描的，這裡也就僅僅以原生二維碼掃面為範例

1.原生掃描用到的幾個類

@property (strong,nonatomic)AVCaptureDevice * device;
@property (strong,nonatomic)AVCaptureDeviceInput * input;
@property (strong,nonatomic)AVCaptureMetadataOutput * output;
@property (strong,nonatomic)AVCaptureSession * session;
@property
 
 (strong,nonatomic)AVCaptureVideoPreviewLayer * preview;

2.在viewDidLoad裡建立它們

// Device
_device = [AVCaptureDevicedefaultDeviceWithMediaType:AVMediaTypeVideo];

// Input
_input = [AVCaptureDeviceInputdeviceInputWithDevice:self.deviceerror:nil];

// Output
_output = [[AVCaptureMetadataOutputalloc]init];
[_outputsetMetadataObjectsDelegate:selfqueue:dispatch_get_main_queue()];

// Session
 

_session = [[AVCaptureSessionalloc]init];
[_sessionsetSessionPreset:AVCaptureSessionPresetHigh];

連線輸入和輸出

if ([_sessioncanAddInput:self.input])
{
    [_sessionaddInput:self.input];
}

if ([_sessioncanAddOutput:self.output])
{
    [_sessionaddOutput:self.output];
}

設定條碼型別

_output.metadataObjectTypes 
 
=@[AVMetadataObjectTypeQRCode];

新增掃描畫面

_preview =[AVCaptureVideoPreviewLayerlayerWithSession:_session];
_preview.videoGravity =AVLayerVideoGravityResizeAspectFill;
_preview.frame =self.view.layer.bounds;
[self.view.layerinsertSublayer:_previewatIndex:0];

開始掃描

[_sessionstartRunning];

最後實現協議AVCaptureMetadataOutputObjectsDelegate
- (void)captureOutput:(AVCaptureOutput )captureOutput didOutputMetadataObjects:(NSArray )metadataObjects fromConnection:(AVCaptureConnection *)connection
{
NSString *stringValue;
if ([metadataObjectscount] >0){
//停止掃描
[_sessionstopRunning];
AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjectsobjectAtIndex:0];
stringValue = metadataObject.stringValue;
}
}