问onMouseOver事件在React中不起作用

EN

class ShowGallery extends React.Component {
  constructor(props) {
    super(props);
    this.state = { currentImage: 0 };
    this.closeLightbox = this.closeLightbox.bind(this);
    this.openLightbox = this.openLightbox.bind(this);
    this.gotoNext = this.gotoNext.bind(this);
    this.gotoPrevious = this.gotoPrevious.bind(this);
    this.gotoImage = this.gotoImage.bind(this);
    this.onMouseEnterHandler = this.onMouseEnterHandler.bind(this, 'value');
    this.onMouseLeaveHandler = this.onMouseLeaveHandler.bind(this, 'value');
  }
  openLightbox(event, obj) {
    this.setState({
      currentImage: obj.index,
      lightboxIsOpen: true
    });
  }
  closeLightbox() {
    this.setState({
      currentImage: 0,
      lightboxIsOpen: false
    });
  }
  gotoPrevious() {
    this.setState({
      currentImage: this.state.currentImage - 1
    });
  }
  gotoNext() {
    this.setState({
      currentImage: this.state.currentImage + 1
    });
  }
  gotoImage(event, obj) {
    this.setState({
      currentImage: obj.index
    });
  }
  onMouseEnterHandler (event, obj) {
    console.log("mouse entered")
  }
  onMouseLeaveHandler (event, obj) {
    console.log("mouse left area")
  }
  render() {
    return (
      <div>
        <Container>
          {this.props.pageData.sectionTitle === "hello" ?(<SectionHeader
            title={this.props.pageData.sectionTitle}
            paragraph={this.props.pageData.blurb}
          />) : null}

          <Col>
          </Col>
        </Container>
        <Row>
          <Col>
            <Gallery
              photos={this.props.pageData.photos}
              onClick={this.openLightbox}
              onMouseOver={() => console.log("mouse over")}
              // onMouseLeave={this.onMouseLeaveHander}
            />
            <Lightbox
              images={this.props.pageData.photos}
              onClose={this.closeLightbox}
              onClickPrev={this.gotoPrevious}
              onClickNext={this.gotoNext}
              currentImage={this.state.currentImage}
              isOpen={this.state.lightboxIsOpen}
              backdropClosesModal={true}
            />
          </Col>
        </Row>
      </div>
    );
  }
}

export default ShowGallery;