The method '[]' was called on null in Flutter - flutter

Question

i want to get the data returned from a method 'getData()' into a List 'datat' but i am getting this error
: ' The method '[]' was called on null '
this is the corresponding code :
ListeMedecinsState() {
/* Fetching Data Into ListView */
Future<String> getData() async {
var response = await http.get(
Uri.encodeFull("http://10.0.2.2:4000/user/GetAllMedecins"),
headers: {
"Accept": "application/json"
}
);
this.setState(() {
this.data = json.decode(response.body);
});
return "Success";
}
getData() ;
print(this.data[1]["email"]);
/* Fetching Data Into ListView */
}
Notice : when i retreive the data into the list inside the method it shows no error, i want to use the data outside of the method scope how can i do please ?

Answer 1

Also, you could do it this way:
getData().then((data){
//do something with data
});

Answer 2

You should await getData();
But please post your full code so it's more understandable.
Thank you

Answer 3

#Sebastian is correct. (so select his answer not mine. I'm only posting here so that you can see the complete code) Your code should read:
ListeMedecinsState() async { // <-- this has to be added as well
/* Fetching Data Into ListView */
Future<String> getData() async {
var response = await http.get(
Uri.encodeFull("http://10.0.2.2:4000/user/GetAllMedecins"),
headers: {
"Accept": "application/json"
}
);
this.setState(() {
this.data = json.decode(response.body);
});
return "Success";
}
await getData() ; // <--- your code needs to pause until the Future returns.
print(this.data[1]["email"]);
/* Fetching Data Into ListView */ }

Answer 4

As Sebastian said, your ListeMedecinState should be asynchronous.
So that you can await the request and only proceed on it completion.
Your code actually doesn't wait for the result of getData() method before proceeding.
So you should await it before trying to access the data fetched !
Hope this helps !
(Seems like you speak French, I speak French too just in case you get lost) :)