question：'package:flutter/src/widegets/text.dart':failed assertion:line 235 pos 15 : 'data ! = NULL ' : is not true code：

body: Container(
     child: FutureBuilder(
       future: _getQu(),
       builder: (BuildContext context, AsyncSnapshot snapshot){
         if (snapshot.data == null){
           return Container(
          child: Center(
            child: Text(" تحميل البينات........"),
          ),
           );
         }Dn.jpg