@mcallistersean/react-githubish-mentions v1.2.2
react-githubish-mentions
A wrapper for a textarea to offers autocomplete suggestions when triggered by @ or # or whatever
Installation
yarn add react-githubish-mentions
What's it do
It strives to do exactly what GitHub does when you type # or @.
How's it different from react-mentions
react-mentions is great! but I needed:
- something a little more flexible (like letting me pass in my own component with avatars for individual Menu items)
- a menu that uses a portal instead of position: 'absolute'
- something with pixel-perfect caret positioning
- something that let's me use controlled components, like redux-form
Usage
Stick it around your component
Example:
// MenuItem.js
const MenuItem = (props) => {
  // react-githubish-mentions provides `active` you provide everything else
  const {active, value} = props;
  const customStyle = {
    background: active ? 'blue' : 'white'
  };
  return (
    <div style={customStyle}>
      {value}
    </div>
  )
};
export default MenuItem;
// in form.js
import {MentionWrapper, MentionMenu} from 'react-githubish-mentions';
import MenuItem from './MenuItem';
const Form = (props) => {
  const atQuery = async (query) => {
    const {teamMembers} = this.props;
    // You must provide a `value` field. Everything else is optional. All this data will be passed to your custom MenuItem
    const tm = teamMembers.map((teamMember) => ({...teamMember, value: teamMember.name}));
    return tm.filter((member) => member.value.startsWith(query))
  };
  return (
    <MentionWrapper placeholder="Type your outcome here">
      <MentionMenu className="mentionMenuStyle" trigger="@" item={MenuItem} resolve={atQuery}/>
      <MentionMenu className="mentionMenuStyle" trigger="#" item={MenuItem} resolve={hashQuery}/>
    </MentionWrapper>
    )
};API
MentionWrapperThink of this as <textarea>. Everything except the 2 options below get passed directly to the HTML component.
Options:
- getRef: a custom- ref, because react yells if you call something ref.
- component: defaults to- "textarea"you can pass in- "input"or even a custom component if you want (TODO)
- onChange(event, newValue): your standard- onChangeevent handler, but with a newValue argument added to support clicking an option with the mouse.
MentionMenuThink of this as a trigger, written in JSX. Any style or className is passed to the menu that will pop up.
Options:
- trigger: The keystroke to watch for. Usually a single character like- @or- #
- replace(trigger, userObject): A function dictating how to autocomplete the sentence. Default is- (userObj, trigger) => `${trigger}${userObj.value} `. If you wanted to write a trigger for emojis, you probably don't want the- :trigger to remain, and you want the character, not the text value, so you might use- (userObj) => `${userObj.emoji} `
- resolve(query): An- AsyncFunctionthat receives a text query (the part after the trigger, e.g.- query('@foo') === 'foo') and returns an array of objects, where each object has a- valuekey which is the string that will be injected into the textarea.
- item: A custom menu item that you provide. See example above.
FAQ
Q: I'm debugging the menu & I don't see it in the DOM tree. What voodoo is this?
A: It's there, but it created a portal & lives in its own react root. This is the only surefire way to guarantee the menu doesn't get clipped or scrolled away. To learn more, see react-portal-hoc
Q: How is the menu position calculated?
A: Very carefully, using textarea-caret.
Until Document.caretPositionFromPoint() is a thing, it's the best there is.
Q: How do I filter the results in my resolve function?
A: There are 100s of ways to filter,
you could go naive with a startsWith or indexOf or go extreme with a
fuzzy or levenshtein distance. Chances are, each trigger will warrant a different filter.
This package does one thing, and does it well. It leaves the filtering up to
your resolve function.
License
MIT