flutter-handling-concurrency

To keep Flutter UI responsive, you offload CPU-bound work like heavy computations to a background worker isolate, freeing the main thread to prevent jank and maintain smooth rendering.

Yes, you can parse large JSON payloads without UI jank by moving the parsing logic into a background isolate using Isolate.run, ensuring the main UI thread remains unblocked.

You use Isolate.run by passing a heavy computation function to it and awaiting the returned result, which executes the task in a separate isolate to keep the UI responsive.

Dart isolates require careful port communication and memory management to prevent leaks, and passing large image data between isolates can introduce overhead that limits performance gains.

You should offload work to a worker isolate when handling data-heavy computations in Flutter apps, specifically tasks that block the main UI thread long enough to cause noticeable unresponsiveness.