Is there any best practice of how to define the widget's properties visibility in Flutter?

Question

In Java, according to the recommendations of Effective Java (Item 15 ["Minimize Mutability"] in the Second Edition and Item 13 ["Favor Immutability"] in the First Edition):

Fields are final and private.

If a field does not intend to be used externally, it's likely to set it to private , eg,

class CustomAppBar extends View {
    public CustomAppBar(Context context, String title, Boolean centerTitle) {
        super(context);
        this.title = title;
        this.centerTitle = centerTitle;
    }
    private final String title;
    private final Boolean centerTitle;
}

But in Flutter framework, almost all Flutter widgets use properties as public property, like what I see in AppBar :

class AppBar extends StatefulWidget implements PreferredSizeWidget {

  AppBar({
    this.title,
    this.centerTitle,
    ...
  }): ...

  final Widget title;
  final bool centerTitle;

  ...
}

But based on the experience I learned from Java, I should make it more reasonable to change the properties to private , such like:

class CustomAppBar extends StatefulWidget implements PreferredSizeWidget {

  CustomAppBar({
    Widget title,
    bool centerTitle,
  }): _title = title,
    _centerTitle = centerTitle;

  final Widget _title;
  final bool _centerTitle;

  ...
}

So I am curious, is there any best practice(effective) guide of the visibility of the properties of Flutter widgets?

Answer 1

From Dart Documentation

Dart doesn't have the keywords public, protected, and private. If an identifier starts with an underscore _, it's private to its Class , so it is different than Java

So as per you code only:

// these are private entities inside your Class/Activity
final Widget _title;
final bool _centerTitle;