How to use the blinkid-react-native.SuccessFrameGrabberRecognizerResult function in blinkid-react-native

localState.results +=
                "First name: " + mrtdResult.mrzResult.secondaryId + fieldDelim +
                "Last name: " + mrtdResult.mrzResult.primaryId + fieldDelim +
                "Nationality: " + mrtdResult.mrzResult.nationality + fieldDelim +
                "Gender: " + mrtdResult.mrzResult.gender + fieldDelim +
                "Date of birth: " +
                    mrtdResult.mrzResult.dateOfBirth.day + "." +
                    mrtdResult.mrzResult.dateOfBirth.month + "." +
                    mrtdResult.mrzResult.dateOfBirth.year + ".";
            
              // Document image is returned as Base64 encoded JPEG
              if (mrtdResult.fullDocumentImage) {
                  localState.showImageDocument = true;
                  localState.resultImageDocument = 'data:image/jpg;base64,' + mrtdResult.fullDocumentImage;
              }
        } else if (result instanceof BlinkIDReactNative.SuccessFrameGrabberRecognizerResult) {
            // first handle slave result, and then add success frame image
            localState = this.handleResult(result.slaveRecognizerResult);
  
              // success frame is returned as Base64 encoded JPEG
            if (result.successFrame) {
                localState.showSuccessFrame = true;
                localState.successFrame = 'data:image/jpg;base64,' + result.successFrame;
            }
        }
        return localState;
    }