Just wrap the logic around setState(){} in onPressed() of floatingActionButton . When on click on the FloatingActionButton with Refresh Icon, the icon is changed to Stop.
Read moreHow do I resize icons in flutter?
You can increase the size of Icon to a required value by assigning the size property with specific double value .
Read moreHow do you customize icons on flutter?
Run flutter pub get in the terminal or click Pub get inside the IDE.
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