Using Popper for Tooltips with TypeScript and Styled-components

July 29, 2020

javascript
typescript
tooltip
styled-components

In this article, I share my journey of creating a customized tooltip using Popper.js in a React application with TypeScript and styled-components.

Introduction

I needed to create a customized tooltip for a project, and Popper.js (https://popper.js.org) came to mind. However, this was my first time using Popper with React, so I needed to familiarize myself with it.

Exploring the Documentation

My first step was to dive into the Popper.js documentation. Right away, it suggested using the hook-based API instead of the older render props API. Since I prefer hooks, this suited me well. The documentation provided a comprehensive example of using hooks, which I found on this page: https://popper.js.org/react-popper/v2/.

Here’s the basic example provided:

import React, { useState } from 'react';
import { usePopper } from 'react-popper';

const Example = () => {
  const [referenceElement, setReferenceElement] = useState(null);
  const [popperElement, setPopperElement] = useState(null);
  const [arrowElement, setArrowElement] = useState(null);
  const { styles, attributes } = usePopper(referenceElement, popperElement, {
    modifiers: [{ name: 'arrow', options: { element: arrowElement } }],
  });

  return (
    <>
      <button type="button" ref={setReferenceElement}>
        Reference element
      </button>

      <div ref={setPopperElement} style={styles.popper} {...attributes.popper}>
        Popper element
        <div ref={setArrowElement} style={styles.arrow} />
      </div>
    </>
  );
};

Adding Styled-components and TypeScript

While the basic example was helpful, I needed to integrate styled-components and TypeScript to fully customize the tooltip. During my research, I found a helpful article on Medium that explained how to use usePopper with styled-components in React: https://medium.com/javascript-in-plain-english/usepopper-with-styled-components-for-react-react-popper-2-568284d029bf. The complete code example is available on CodeSandbox: https://codesandbox.io/s/blue-worker-w9rtu?file=/src/App.js.

Implementing the Tooltip

Here’s how I implemented the tooltip using usePopper, styled-components, and TypeScript:

import React, { useState, useRef } from 'react';
import { usePopper } from 'react-popper';
import styled from 'styled-components';

const Dropdown = () => {
  const [showPopper, setShowPopper] = useState(false);

  const buttonRef = useRef(null);
  const popperRef = useRef(null);
  // the ref for the arrow must be a callback ref
  const [arrowRef, setArrowRef] = useState(null);

  const { styles, attributes } = usePopper(buttonRef.current, popperRef.current, {
    modifiers: [
      {
        name: 'arrow',
        options: {
          element: arrowRef,
        },
      },
      {
        name: 'offset',
        options: {
          offset: [0, 10],
        },
      },
    ],
  });

  return (
    <Page>
      <Info>
        <p>Scroll down and right to find the popper!</p>
      </Info>
      <Button ref={buttonRef} onClick={() => setShowPopper(!showPopper)}>
        Click Me
      </Button>
      {showPopper ? (
        <PopperContainer ref={popperRef} style={styles.popper} {...attributes.popper}>
          <div ref={setArrowRef} style={styles.arrow} id="arrow" />
          <p>I'm a popper</p>
        </PopperContainer>
      ) : null}
    </Page>
  );
};

// Basic page styling
const Page = styled.div`
  width: 250%;
  height: 250%;
  display: flex;
  align-items: center;
  justify-content: space-around;
`;

const Info = styled.div`
  background: lightgreen;
  padding: 1rem;
  position: absolute;
  top: 20px;
  left: 20px;
`;

const Button = styled.button`
  background: lightblue;
  border: none;
  box-shadow: 1px 1px 1px rgba(0, 0, 0, 0.3);
  width: 150px;
  height: 50px;
  outline: none;
`;

const PopperContainer = styled.div`
  box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
  border-radius: 5px;
  background-color: white;
  padding: 20px;
  text-align: center;

  #arrow {
    position: absolute;
    width: 10px;
    height: 10px;
    &:after {
      content: ' ';
      background-color: white;
      box-shadow: -1px -1px 1px rgba(0, 0, 0, 0.1);
      position: absolute;
      top: -25px; // padding + popper height
      left: 0;
      transform: rotate(45deg);
      width: 10px;
      height: 10px;
    }
  }

  &[data-popper-placement^='top'] > #arrow {
    bottom: -30px;
    :after {
      box-shadow: 1px 1px 1px rgba(0, 0, 0, 0.1);
    }
  }
`;

Handling TypeScript Issues

Initially, I encountered a TypeScript error when setting the ref for the arrow element:

<div ref={setArrowRef} style={styles.arrow} className="arrow" />

The error was:

Type 'Dispatch<SetStateAction<null>>' is not assignable to type 'string | ((instance: HTMLDivElement | null) => void) | RefObject<HTMLDivElement> | null | undefined'.
  Type 'Dispatch<SetStateAction<null>>' is not assignable to type '(instance: HTMLDivElement | null) => void'.
    Types of parameters 'value' and 'instance' are incompatible.
      Type 'HTMLDivElement | null' is not assignable to type 'SetStateAction<null>'.
        Type 'HTMLDivElement' is not assignable to type 'SetStateAction<null>'.
          Type 'HTMLDivElement' provides no match for the signature '(prevState: null): null'

To resolve this, I typed the useState hook like this:

- const [arrowRef, setArrowRef] = useState(null);
+ const [arrowRef, setArrowRef] = useState<HTMLDivElement | null>(null);

This resolved the issue, and you can see the complete working example here: https://codesandbox.io/s/usepopper-styled-components-xblqg?file=/src/components/Tooltip.tsx:317-390.

Conclusion

Integrating Popper.js with styled-components and TypeScript can enhance the functionality and appearance of your tooltips. This approach provides a robust and flexible way to manage tooltips in a React application. If you found this article helpful or have any suggestions, please feel free to comment or share.