setItem

counterkey

json

stringify

++

this

state

counter

));

AsyncStorage

getItem

counterkey

).

then

value

=>

if

value

!=

null

this

setState

({

counter

value

});

});

shared_preferences plugin to
store and retrieve key-value data that is persistent and global
to the app. The

dependencies

flutter

sdk

flutter

shared_preferences

^2.0.13

Routing