Problem Statement
Why should you use const constructors for widgets when possible?
Explanation
Using const constructors tells Flutter that the widget is completely immutable and can be reused across rebuilds without creating new instances. When Flutter sees a const widget, it knows the widget hasn't changed and can skip rebuilding that part of the tree entirely, significantly improving performance especially in frequently rebuilt parts of the UI.
Const widgets are canonicalized, meaning identical const widgets share the same instance in memory, reducing memory allocation. When a parent rebuilds, const children are guaranteed to be the same instance, so Flutter's reconciliation algorithm knows it can reuse the corresponding Element and RenderObject without any work.
Use const constructors whenever a widget and all its properties are compile-time constants that won't change. This is common for static UI elements like Text('Hello'), Icons, Padding with fixed values, and decorative elements. The Flutter analyzer will suggest adding const where possible, helping you optimize performance with minimal effort.
