The error “Closure: ()=> Map from Function ‘toJson’” usually occurs when there is an issue with converting a class instance to a JSON object. Here are methods to solve this issue Step-by-Step Guide: Avoid Using Closures in toJson: Ensure no closures are being returned by the toJson method. It should directly return a map. Check…
Month: June 2024
Flutter Sign-In Page: Using Bloc with StatefulWidget vs StatelessWidget
In a Flutter application, the choice between using a StatefulWidget and a StatelessWidget often depends on how you manage the state and the specific requirements of your user interface. When using the Bloc pattern for state management, you might wonder why a StatefulWidget is still necessary if Bloc is handling the state. Here’s an explanation:…
Fixing setState() Error During Build in Flutter: Using addPostFrameCallback for Safe State Updates
The addPostFrameCallback method solves the problem because it schedules the callback to be executed after the current frame has been rendered. Here’s a detailed explanation of why this approach works: Understanding the Error The error message Unhandled Exception: setState() or markNeedsBuild() called during build indicates that setState() was called during the widget’s build phase. This…
Understanding Flutter BLoC: How to Trigger Events on Page Load in Stateless Widgets
Introduction Flutter is a powerful framework for building cross-platform applications, and the BLoC (Business Logic Component) pattern is a popular state management solution in the Flutter ecosystem. One common challenge is triggering an event when a stateless widget is first built. This article will provide a clear, step-by-step example of how to accomplish this using…
Using the extra Parameter with go_router for Nested Routes
When building complex applications, you often need to pass more information than what can be neatly included in URL parameters. The go_router package in Flutter provides the extra parameter, allowing you to pass additional data (such as complex objects or additional information) along with your navigation. 1. Add Dependencies First, ensure that you have the…