The method '[]' can't be unconditionally invoked because the receiver can be 'null'
you can just add the type of the future you are using like this one
//this one wont work
body: FutureBuilder(
future:getDataFromJason(),
builder: (ctx, snapShot) {
if(snapShot.connectionState==ConnectionState.waiting){
return Center(child: CircularProgressIndicator());
}
else{}
//but this will just add the type of futureBuilder
body: FutureBuilder<dynamic>(
future:getDataFromJason(),
builder: (ctx, snapShot) {
if(snapShot.connectionState==ConnectionState.waiting){
return Center(child: CircularProgressIndicator());
}
else{