runOnUISync

runOnUISync lets you run a workletized function synchronously on the UI Runtime.

To compare it with scheduleOnUI and runOnUIAsync, see Running worklet functions on the UI runtime.

Reference

Code

Code

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1function myFunction(num) {

2 'worklet';

3 return num + 1;

4}

5

6const result = runOnUISync(myFunction, 0);

7console.log(result); // 1

Type definitions

function runOnUISync<Args extends unknown[], ReturnValue>(
  worklet: (...args: Args) => ReturnValue,
  ...args: Args
): ReturnValue;

Arguments

worklet

A function you want to execute on the UI Runtime.

args

Arguments to pass to the function.

Returns

runOnUISync returns the return value of the function passed as the first argument. It can only return values that can be converted to a Serializable.

Remarks

• The callback passed as the argument is automatically workletized and ready to be run on the UI Runtime.

Call table

Mode	RN Runtime	UI Runtime	Worker Runtime
Bundle Mode	✅	✅	✅
Legacy Eval Mode	✅	❌	❌

What does it mean?

Platform compatibility

Native	Web
✅	❌