Flutter's FutureBuilder Widget Simplifies Displaying Async Data in UI

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Flutter's build method is synchronous and cannot natively wait for asynchronous operations like API calls to complete before rendering the UI. The FutureBuilder widget addresses this limitation by accepting a Future value and rebuilding the UI as the asynchronous state changes. Developers can use its snapshot object to handle three distinct states: loading, error, and data-available, each rendering a different widget. A practical example involves a weather app that shows a loading spinner while fetching temperature data, then displays the result or an error message once the Future resolves. FutureBuilder requires only two parameters — future and builder — making it one of the more straightforward widgets in the Flutter framework.

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