Tldraw/apps/examples
alex 2d2a7ea76f
Fix multiple editor instances issue (#4001)
React's strict mode runs effects twice on mount, but once it's done that
it'll go forward with the state from the first effect. For example, this
component:

```tsx
let nextId = 1
function Component() {
	const [state, setState] = useState(null)
	useEffect(() => {
		const id = nextId++
		console.log('set up', id)
		setState(id)
		return () => console.log('tear down', id)
	}, [])
	if (!state) return
	console.log('render', state)
}
```

Would log something like this when mounting for the first time:
- `set up 1`
- `tear down 1`
- `set up 2`
- `render 1`

For us, this is a problem: editor 2 is the version that's still running,
but editor 1 is getting used for render. React talks a bit about this
issue here: https://github.com/reactwg/react-18/discussions/19

The fix seems to be to keep the editor in a `useRef` instead of a
`useState`. We need the state to trigger re-renders though, so we sync
the ref into the state although we don't actually use the state value.

### Change Type


- [x] `sdk` — Changes the tldraw SDK
- [x] `bugfix` — Bug fix



### Release Notes

- Fix a bug causing text shape measurement to work incorrectly when
using react strict mode
2024-06-24 12:24:24 +00:00
..
e2e
public
src Fix multiple editor instances issue (#4001) 2024-06-24 12:24:24 +00:00
.gitignore
LICENSE.md
README.md
package.json
tsconfig.json
vercel.json
vite.config.ts Add tags to examples frontmatter (#3929) 2024-06-18 10:47:42 +00:00

README.md

@tldraw/example

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