Flutter Provider is returning null in initState() - flutter

Question

I am getting List of DropdownMenuItem from firebase with stream using provider if I use provider in build it doesn't return null works great but in initstate even if I am setting the listen value false returns null.
Here is the code:
List<DropdownMenuItem<category.List>> dropdownmenuoptions;
DropdownMenuItem<category.List> dropdownMenuItem;
String dropDownValue;
#override
void initState() {
dropdownmenuoptions = Provider.of<List<DropdownMenuItem<category.List>>>(
context,
listen: false);
dropdownMenuItem = dropdownmenuoptions.first;
dropDownValue = dropdownMenuItem.value.name;
super.initState();
}
Here is the error message:
The following NoSuchMethodError was thrown building Builder:
The getter 'first' was called on null.
Receiver: null
Tried calling: first
The relevant error-causing widget was
MaterialApp
lib/main.dart:37
When the exception was thrown, this was the stack
#0 Object.noSuchMethod (dart:core-patch/object_patch.dart:51:5)
#1 _HomeScreenState.initState
package:tobetter/…/home/home_screen.dart:73
#2 StatefulElement._firstBuild
package:flutter/…/widgets/framework.dart:4833
#3 ComponentElement.mount
package:flutter/…/widgets/framework.dart:4649
... Normal element mounting (24 frames)

Answer 1

The direct context inside initState can't be used for everything and specialty with Provider . so, as a solution use didChangeDependencies instead , example:
#override
void didChangeDependencies() {
super.didChangeDependencies();
dropdownmenuoptions = Provider.of<List<DropdownMenuItem<category.List>>>(
context,
listen: false);
dropdownMenuItem = dropdownmenuoptions.first;
dropDownValue = dropdownMenuItem.value.name;
}
if you really need it inside your initState you can use it inside addPostFrameCallback
#override
void initState(){
...
SchedulerBinding.instance.addPostFrameCallback((_) {
dropdownmenuoptions = Provider.of<List<DropdownMenuItem<category.List>>>(
context,
listen: false);
dropdownMenuItem = dropdownmenuoptions.first;
dropDownValue = dropdownMenuItem.value.name;
}
});