#371 TDPFQRCodeScanneris not reading all Bar codes?

[Shujaat Hussain]

I am using TDPFQRCodeScanner to read bar codes. It's unable to read all kinds of bar codes. I have updated the "CreateUIControl" and "CaptureOutput" procedures of the DPF components BarCodeReader class as:

procedure TDPFQRCodeScanner.CreateUIControl;
{$IFDEF IOS}
var
device : AVCaptureDevice;
error : Pointer;
input : AVCaptureDeviceInput;
LOutput : AVCaptureMetadataOutput;
ObjTypes: NSMutableArray;
{$ENDIF}
begin
{$IFDEF IOS}
if Assigned( FNativeControl ) then
Exit;

FNativeControl := TUIView.Create;
FUIControl := FNativeControl;

if IsCameraAvailable then
begin
FSession := TAVCaptureSession.Create;
device := TAVCaptureDevice.Wrap( TAVCaptureDevice.OCClass.defaultDeviceWithMediaType( AVMediaTypeVideo ) );

error := nil;
input := TAVCaptureDeviceInput.Wrap( TAVCaptureDeviceInput.OCClass.deviceInputWithDevice( device, @error ) );
if Assigned( input ) then
  FSession.addInput( input )
else
begin
  if Assigned( FOnError ) and Assigned( error ) then
    FOnError( Self, error );
end;

LOutput := TAVCaptureMetadataOutput.Wrap( TAVCaptureMetadataOutput.Wrap( TAVCaptureMetadataOutput.OCClass.alloc ).init );

FSession.addOutput( LOutput ); // important: must be done before setting metadata object types!

ObjTypes := TNSMutableArray.Create; // TNSMutableArray.Wrap(TNSMutableArray.OCClass.arrayWithObject((AVMetadataObjectTypeQRCode as ILocalObject).GetObjectID));
//ObjTypes.addObject( ( AVMetadataObjectTypeQRCode as ILocalObject ).GetObjectID );

ObjTypes.addObject((AVMetadataObjectTypeUPCECode        as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeCode39Code      as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeCode39Mod43Code as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeEAN13Code       as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeEAN8Code        as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeCode93Code      as ILocalObject).GetObjectID);
ObjTypes.addObject( ( AVMetadataObjectTypeCode128Code   as ILocalObject ).GetObjectID );
ObjTypes.addObject((AVMetadataObjectTypePDF417Code      as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeAztecCode       as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeInterleaved2of5Code   as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeITF14Code             as ILocalObject).GetObjectID);
ObjTypes.addObject((AVMetadataObjectTypeDataMatrixCode        as ILocalObject).GetObjectID);

LOutput.setMetadataObjectTypes( ObjTypes );
LOutput.setMetadataObjectsDelegate( ( FDelegate as ILocalObject ).GetObjectID, dispatch_get_main_queue( ) );

LOutput.release;
LOutput := nil;

Fpreview := TAVCaptureVideoPreviewLayer.Wrap( TAVCaptureVideoPreviewLayer.OCClass.layerWithSession( FSession ) );
Fpreview.setVideoGravity( AVLayerVideoGravityResizeAspectFill );
Fpreview.setframe( CGRectMake( 0, 0, FNativeControl.frame.size.width, FNativeControl.frame.size.height ) );

UpdateOrientation;

FNativeControl.layer.insertSublayer( FPreview, 0 );

end;
{$ENDIF}
inherited CreateUIControl;
end;

procedure TCaptureDelegate.captureOutput( captureOutput: AVCaptureOutput; didOutputMetadataObjects: NSArray; fromConnection: AVCaptureConnection );
var
QRCode : NSString;
metadata: AVMetadataObject;
I : Integer; //AVMetadataObjectTypeQRCode or

begin
for I := 0 to didOutputMetadataObjects.count - 1 do
begin
metadata := TAVMetadataObject.Wrap( didOutputMetadataObjects.objectAtIndex( I ) );
if metadata.&type.isEqualToString(AVMetadataObjectTypeCode128Code)then
begin
QRCode := TAVMetadataMachineReadableCodeObject.Wrap( ( metadata as ILocalObject ).GetObjectID ).stringValue;
DoOnScan( NSStrToStr( QRCode ) );
break;
end
else if metadata.&type.isEqualToString(AVMetadataObjectTypeCode128Code) then
begin
QRCode := TAVMetadataMachineReadableCodeObject.Wrap( ( metadata as ILocalObject ).GetObjectID ).stringValue;
DoOnScan( NSStrToStr( QRCode ) );
break;
end
else if metadata.&type.isEqualToString(AVMetadataObjectTypeCode128Code) then
begin
QRCode := TAVMetadataMachineReadableCodeObject.Wrap( ( metadata as ILocalObject ).GetObjectID ).stringValue;
DoOnScan( NSStrToStr( QRCode ) );
break;
end
else
begin
QRCode := TAVMetadataMachineReadableCodeObject.Wrap( ( metadata as ILocalObject ).GetObjectID ).stringValue;
DoOnScan( NSStrToStr( QRCode ) );
break;
end;
// NSLog(@"QR Code: %@", QRCode);
end;
end;

But it's not working for me. Can you please guide me through it?

[Shujaat Hussain]