isUIRuntime
Available from 0.8.0
Checks if the current runtime is the UI Runtime.
Reference
Code
Code
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function checkUI() {
'worklet';
console.log(isUIRuntime()); // true (UI Runtime)
}
function checkWorker() {
'worklet';
console.log(isUIRuntime()); // false (Worker Runtime)
}
console.log(isUIRuntime()); // false (RN Runtime)
scheduleOnUI(checkUI);
const workerRuntime = createWorkletRuntime({ name: 'background' });
scheduleOnRuntime(workerRuntime, checkWorker);
Console 0
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Output appears here as the code runs.


Type definitions
function isUIRuntime(): boolean;
Returns
true if the current runtime is the UI Runtime, false otherwise.
Remarks
- The function checks the value of
globalThis.__RUNTIME_KINDto determine the kind of the current runtime. See getRuntimeKind for more details.