Скачать или смотреть How to Position Tooltip Relative to Selected Text in a React Textarea

Learn how to create a tooltip in React that displays the selected text in a textarea and positions itself correctly just below the text.
---
This video is based on the question https://stackoverflow.com/q/64623552/ asked by the user 'Alexander Juhl' ( https://stackoverflow.com/u/8559157/ ) and on the answer https://stackoverflow.com/a/64632215/ provided by the user 'Alexander Juhl' ( https://stackoverflow.com/u/8559157/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: How to set elements xy-position relative to selected text in another element?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Creating a Tooltip in React: Positioning It Under Selected Text

If you're working on a React application and want to build a tooltip that displays information based on the text selected by a user in a textarea, you might face the challenge of positioning that tooltip accurately. How do you get it to display just below the selected text? This guide walks you through the solution, using the getBoundingClientRect method for precise positioning.

The Challenge

Imagine you're building a simple user interface where users can select text in a textarea, and you want to display that selected text in a tooltip. At first glance, you might be able to display the tooltip, but getting it to align properly under the highlighted text can be troublesome. In this guide, we’re going to solve this challenge step-by-step.

The Initial Code

Here’s the React component we started with:

[[See Video to Reveal this Text or Code Snippet]]

The Problem

The problem here is that while the tooltip appears when text is selected, it does not correctly position itself just below that selected text. The original code sets the tooltip’s position based on the mouse event, which isn’t the correct logic for aligning with the selected text.

The Solution: Using getBoundingClientRect

To accurately position the tooltip beneath the selected text, we can leverage the getBoundingClientRect method. This method returns the size of an element and its position relative to the viewport.

Step-by-Step Implementation

Use Two Refs: We need to create two useRef hooks, one for the tooltip and one for the textarea itself.

Update Tooltip Positioning: Modify the mouse up handler to adjust the tooltip's positioning based on the bounding rectangle of the textarea.

Here's the revised code:

[[See Video to Reveal this Text or Code Snippet]]

Explanation of Changes

Use of getBoundingClientRect: The tooltips' positions for top and left are calculated based on the coordinates of the textarea obtained from getBoundingClientRect() plus the current mouse event coordinates. This ensures that the tooltip appears right underneath the selected text regardless of where the mouse is clicked.

Styling the Tooltip: The tooltip's display and style are conditioned upon whether any text is selected; otherwise, it remains hidden.

Conclusion

By implementing these adjustments, you can create a responsive tooltip in your React application that effectively displays selected text in a textarea at the appropriate position. Using getBoundingClientRect helps in achieving accurate placement, improving the user experience significantly.

Now go ahead and implement this tooltip functionality in your project, and enhance the interactivity of your application!