What is runZonedGuarded Function in Flutter ?

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In Flutter, the runZonedGuarded function is a way to run a block of code (a callback) within a special zone while also providing a custom error handler to handle any uncaught exceptions that may occur during the execution of that code. This is often used for managing and handling errors in asynchronous code, such as when working with Futures or Streams.

Here’s a breakdown of its purpose:

1. Zones: In Dart, zones are a way to isolate and capture asynchronous errors that occur within a particular scope of code. They allow you to handle errors or exceptions gracefully, preventing them from crashing the entire application.

2. runZonedGuarded: This function takes two main arguments:

• A callback function: This is the code that you want to run within a specific zone. Any errors thrown within this callback will be captured and handled by the error handler.
• An error handler function: This function is responsible for handling any uncaught exceptions that occur within the callback. It receives two arguments: the error itself and a stack trace.

Here’s a basic example of how runZonedGuarded might be used in Flutter:

runZonedGuarded(() {
  // Your code that may throw exceptions
  final result = 1 ~/ 0; // This will throw a 'Division by zero' exception
}, (error, stackTrace) {
  // Custom error handling logic
  print('Error: $error');
  print('Stack Trace: $stackTrace');
});

/* The rest of your Flutter application continues running even 
 if an error occurs within the callback. */

In this example, if an exception is thrown within the callback (in this case, a division by zero error), it will be caught and handled by the error handler. This prevents the exception from crashing the entire Flutter application and allows you to log, report, or handle the error in a more controlled manner.

runZonedGuarded is particularly useful in scenarios where you want to ensure that your application can gracefully handle errors and continue running even if unexpected exceptions occur in specific parts of your code.