Approach 1: Create a ValueChanged from Parent Widget add pass to FirstWidget, when change couter -> call ValueChanged to send update to Parent Widget, Parent will update state for second Widget.
Read moreHow do you call a function from another in Dart?
You can do that in different ways:
Read moreHow do you call a method from another widget in flutter?
Calling a method of child widget from a parent widget is discouraged in Flutter. Instead, Flutter encourages you to pass down the state of a child as constructor parameters. Instead of calling a method of the child, you just call setState in the parent widget to update its children .
Read moreHow do you call a method from another class flutter?
To call a void function from another file in Flutter, what you have to do are:
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