[Solved]-React-bootstrap tooltip not firing-Reactjs

You don't actually need to write a custom method for that, react-bootstrap has that built in. Check out the documentation: https://react-bootstrap.github.io/components.html#tooltips

You will have to put a <Tooltip/> element as an overlay prop in an OverlayTrigger.

var tooltip = <Tooltip />;
// ...
<OverlayTrigger placement="left" overlay={tooltip}>
  <td>Holy guacamole!</td>
</OverlayTrigger>

Or, if that breaks the layout:

var tooltip = <Tooltip />;
// ...

<td>
  <OverlayTrigger placement="left" overlay={tooltip}>
    Holy guacamole!
  </OverlayTrigger>
</td>

This code will have to be in the render() method. What you are doing right now is you just return a JSX element into nowhere, that's why the tooltip doesn't show up. It's not rendered or referenced properly in the render() method of your component.