Is it possible to listen for changes, and upon a change, get those new values from a separate class and update variable in current class?

Issue

So, I am in my home_screen dart file and I have a Text in it where I want it to display the live value from another class's properties value. When I update the class's properties value from another script I want my home_screen Text to update to that new value. My class in a separate file is the following (simplified) :

class MyClass {

  static int myNumber = 10;

}

I want the following Text to update with the value of myNumber in another file:

Text('iWantThisToDisplayLiveMyNumber'),

When I change the value of myNumber from yet another random script how do I get the Text to update in live time to always be myNumber?

Solution

Look into Providers.

class MyClass with ChangeNotifier {

  static int myNumber = 10;

        void changeNumber(){
        myNumber = 1;
        notifyListeners();
    }


 }

In your Widget class you can set up a "listener" like this:

int updatedNumber = Provider.of<MyClass>(context, listen: true).myNumber;

This is a basic and bad way of doing this. Please check out the "ChangeNotifier" "ChangeNotifierProvider" and "Provider.of" Sections in the docs here.

https://flutter.dev/docs/development/data-and-backend/state-mgmt/simple

Its pretty easy to get started with. Good luck

Answered By - Benedikt J Schlegel