How to call Future Function to another class in flutter? - function

Question

I am new in flutter. I created Drawer and loaded its header data from server by creating a future function. I want to recall this future function again from another class, so how can i do that.
I also tried to call by creating its class object like -
Drawersetting object = new Drawersetting();
then - > object.function_name
But that function is not visible.
How to do that? Following whole class - >
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:mera_interest_flutter/Activity/BottomNavBar.dart';
import 'package:mera_interest_flutter/Activity/Login.dart';
import 'package:mera_interest_flutter/Custom/CustomClass.dart';
import 'package:mera_interest_flutter/Fragments/AppHistoryTabScreen.dart';
import 'package:mera_interest_flutter/Fragments/NotificationFragment.dart';
import 'package:mera_interest_flutter/Fragments/PartnersScreen.dart';
import 'package:mera_interest_flutter/Network/BaseURLHeaders.dart';
import 'package:mera_interest_flutter/model/UserInfoDataModel.dart';
import 'package:mera_interest_flutter/model/UserInfoModel.dart';
import 'package:mera_interest_flutter/routes/Routes.dart';
import '../Fragments/DiscoverScreen.dart';
import 'package:flutter_session/flutter_session.dart';
import 'package:mera_interest_flutter/Activity/UserProfileScreen.dart';
import 'package:mera_interest_flutter/Fragments/AddManualFragment.dart';
import 'package:mera_interest_flutter/Fragments/ContactUsScreen.dart';
import 'package:mera_interest_flutter/Fragments/FAQFragment.dart';
import 'package:mera_interest_flutter/Fragments/MessageFragment.dart';
import '../Fragments/HomeFragment.dart';
import '../Fragments/ZeroBalancePortFolioScreen.dart';
import '../Fragments/SupportFragment.dart';
import 'package:flutter_session/flutter_session.dart';
import 'package:http/http.dart' as http;
//for setting title name of side bar items
class DrawerItem {
String title;
IconData icon;
DrawerItem(this.title, this.icon);
}
//for setting title name of bottom bar items
// class widgetBottomItems{
// String title;
// IconData icon;
// widgetBottomItems(this.title, this.icon);
// }
class DrawerSetting extends StatefulWidget {
final drawerItems = [
new DrawerItem("Portfolio", Icons.add),
new DrawerItem("Zero Balance Portfolio", Icons.alarm),
new DrawerItem("Message", Icons.message),
new DrawerItem("My Info & Setting", Icons.settings),
new DrawerItem("Support", Icons.help),
new DrawerItem("FAQ", Icons.book_outlined),
new DrawerItem("Contact Us", Icons.contact_phone_outlined),
new DrawerItem("Logout", Icons.logout)
];
#override
State<StatefulWidget> createState() {
return new HomePageState();
}
}
class HomePageState extends State<DrawerSetting> {
String _title;
var session = FlutterSession();
#override
void initState() {
// TODO: implement initState
super.initState();
getUserData();
_title ="Discover";
}
void didUpdateWidget(covariant DrawerSetting oldWidget) {
// TODO: implement didUpdateWidget
super.didUpdateWidget(oldWidget);
setState(() {
getUserData();
getNewProfile();
});
}
bool is_new_profile = false;
void getNewProfile()async{
is_new_profile = await session.get("is_new_profile");
print("sessionvalue = " + is_new_profile.toString());
if(is_new_profile == true){
setState(() {
getUserData();
});
}
}
final Color myColor = Color(0xFF15A2EB);
final Color myColorLightGray = Color(0xFF989E9E);
final Color text_Semi_Black_Color = Color(0xFF414B51);
final Color text_gray_color = Color(0xFF70787C);
UserInfoDataModel _userInfoDataModel;
String url = BaseURLHeaders().getBaseURl() + "";
Map headers = BaseURLHeaders().getHeader();
//bottom navigation
int _selectedIndex = 0;
var _screens = [
DiscoverScreen(),
HomeFragment(),
PartnersScreen(),
// HistoryScreen(),
AppHistoryTabScreen(),
NotificationFragment(),
];
static const TextStyle optionStyle = TextStyle(
fontSize: 16,
fontWeight: FontWeight.bold,
color: Colors.red,
fontFamily: "verdana_regular",
);
//for bottom items
void _onItemTapped(int index) {
setState(() {
_selectedIndex = index;
switch(index) {
case 0: { _title = 'Discover'; }
break;
case 1: { _title = 'Portfolio'; }
break;
case 2: { _title = 'Partners'; }
break;
case 3: { _title = 'History'; }
break;
}
});
}
int _selectedDrawerIndex = 0;
String currentProfilePic =
"https://service2home.in/wp-content/uploads/2021/01/rakesh.jpg";
_getDrawerItemWidget(int pos) {
switch (pos) {
case 0:
return new AddManualFdFragment();
break;
case 1:
return new ZeroBalancePortFolioScreen();
break;
case 2:
return MessageFragment();
break;
case 3:
return new UserProfileScreen("drawer");
break;
case 4:
return new SupportFragment();
break;
case 5:
return new FAQFragment();
break;
case 6:
return new ContactUsScreen();
break;
case 7:
SystemNavigator.pop();
//exit(0);
break;
}
}
//for drawer items
_onSelectItem(int index) {
setState(() => _selectedDrawerIndex = index);
Navigator.of(context).pop(); // close the drawer
}
#override
Widget build(BuildContext context) {
//set portrait by default
SystemChrome.setPreferredOrientations([
DeviceOrientation.portraitUp,
DeviceOrientation.portraitDown,
]);
List<Widget> drawerOptions = [];
for (var i = 0; i < widget.drawerItems.length; i++) {
var d = widget.drawerItems[i];
drawerOptions.add(new ListTile(
leading: new Icon(
d.icon,
),
title: new Text(
d.title,
style: TextStyle(
fontSize: 16,
color: myColorLightGray,
fontFamily: "verdana_regular",
),
),
selected: i == _selectedDrawerIndex,
onTap: () => _onSelectItem(i),
));
}
//on backpress return to home screen , you can use it for drawer items
return WillPopScope(
onWillPop: () {
if (_selectedIndex != 0 || _selectedDrawerIndex != 0) {
setState(() {
_selectedIndex = 0;
});
// _getDrawerItemWidget(_selectedIndex);
} else {
Navigator.pop(context, true);
}
return;
},
child: Scaffold(
appBar: new AppBar(
title: Row(
children: [
Expanded(
child: new Text(
_title,
style: TextStyle(
color: Colors.white,
fontSize: 16,
fontFamily: "verdana_regular"),
),
),
Expanded(
flex: 0,
child: Container(
margin: EdgeInsets.only(left: 80),
// width: MediaQuery.of(context).size.width * 0.25,
child: IconButton(
alignment: Alignment.centerRight,
icon: Icon(Icons.notifications_none),
onPressed: () => {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) =>
NotificationFragment())),
}),
),
),
],
),
),
drawer: new Drawer(
child: SingleChildScrollView(
child: new Column(
children: [
//header
UserAccountsDrawerHeader(
currentAccountPicture: Container(
child: new GestureDetector(
child: new Container(
decoration: new BoxDecoration(
shape: BoxShape.circle,
image: _userInfoDataModel != null
? new DecorationImage(
fit: BoxFit.cover,
image: new NetworkImage(
_userInfoDataModel
.profile_url)) :
new DecorationImage(
fit: BoxFit.cover,
image: new AssetImage("assets/images/user.png"),
),
)
),
onTap: () => {
Navigator.of(context).pop(),
Navigator.push(
context,
MaterialPageRoute(
builder: (context) =>
UserProfileScreen("header")),
),
}),
),
accountName: _userInfoDataModel !=null ? new Text(
_userInfoDataModel.first_name + " " + _userInfoDataModel.last_name,
style: TextStyle(
fontSize: 18,
color: Colors.black,
fontFamily: "verdana_regular",
),
) : null,
accountEmail: _userInfoDataModel !=null ? new Text(
_userInfoDataModel.email,
style: TextStyle(
fontSize: 15,
color: Colors.white,
fontFamily: "verdana_regular",
),
) : null,
),
Column(children: [
ListTile(
leading: Icon(Icons.add),
title: Text(
'Add Manual FD',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
Navigator.of(context).pop();
// Navigator.pushReplacementNamed(context, Routes.addFd);
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => AddManualFdFragment()));
}),
ListTile(
leading: Icon(Icons.alarm),
title: Text(
'Zero Balance Portfolio',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
Navigator.of(context).pop();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) =>
ZeroBalancePortFolioScreen()));
}),
ListTile(
leading: Icon(Icons.message),
title: Text(
'Message',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
Navigator.of(context).pop();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => MessageFragment()));
}),
ListTile(
leading: Icon(Icons.settings),
title: Text(
'MY Info & Setting',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
Navigator.of(context).pop();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) =>
UserProfileScreen("header")));
}),
ListTile(
leading: Icon(Icons.help),
title: Text(
'Support',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
Navigator.of(context).pop();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => SupportFragment()));
}),
ListTile(
leading: Icon(Icons.bookmarks_outlined),
title: Text(
'FAQ',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
Navigator.of(context).pop();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => FAQFragment()));
}),
ListTile(
leading: Icon(Icons.contact_phone_outlined),
title: Text(
'Contact Us',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
Navigator.of(context).pop();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => ContactUsScreen()));
}),
ListTile(
leading: Icon(Icons.logout),
title: Text(
'Logout',
style: TextStyle(
color: myColorLightGray,
fontSize: 15,
fontFamily: "verdana_regular",
),
),
onTap: () {
goToLogin();
}),
])
],
),
),
),
body: _screens[_selectedIndex],
/*_getDrawerItemWidget(_selectedDrawerIndex),*/
bottomNavigationBar: BottomNavigationBar(
type: BottomNavigationBarType.fixed,
backgroundColor: myColor,
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.search),
label: 'Discover',
),
BottomNavigationBarItem(
icon: ImageIcon(
AssetImage("assets/images/briefcase.png"),
// color: Colors.grey,
),
label: 'Portfolio',
),
BottomNavigationBarItem(
icon: ImageIcon(
AssetImage("assets/images/partner.png"),
// color: Colors.grey,
),
label: 'Partners',
),
BottomNavigationBarItem(
icon: Icon(Icons.history),
label: 'History',
),
],
currentIndex: _selectedIndex,
selectedItemColor: Colors.black,
unselectedItemColor: Colors.white,
onTap: _onItemTapped,
),
// bottomNavigationBar: BottomNavigationBar(),
),
);
}
//go to news detail page
void goToProfile_Screen(BuildContext ctx) {
Navigator.of(ctx).push(
MaterialPageRoute(
builder: (_) {
return UserProfileScreen("drawer");
},
),
);
}
//logout
Future<void> goToLogin() async {
Navigator.pushReplacement(
context, MaterialPageRoute(builder: (BuildContext context) => Login()));
await FlutterSession().set("isLogin", false);
await FlutterSession().set("user_id", "");
await FlutterSession().set("user_name", "");
await FlutterSession().set("email", "");
await FlutterSession().set("phone", "");
await FlutterSession().set("account_status", "");
await FlutterSession().set("isNewData", false);
}
//api get user info
Future<UserInfoModel> getUserData() async {
String user_id = "1";
var mapData = new Map<String, dynamic>();
mapData['user_id'] = user_id;
// mapData['first_name'] = firstName;
var response = await http.post(
url,
headers: headers,
body: mapData,
);
if (response.statusCode == 200) {
var res = json.decode(response.body);
UserInfoModel _userInfoModel = UserInfoModel.fromJson(res);
if (_userInfoModel.success == 1) {
var data = res["data"];
_userInfoDataModel = UserInfoDataModel.fromJson(data);
// Toast.show("User Data Fetched", context,
// duration: Toast.LENGTH_SHORT, gravity: Toast.TOP);
// CustomClass().makeToast("message", context);
setState(() {
print("responseBody: ${res}");
print("responseData: ${data}");
print("userInfoSuccess: ${_userInfoModel.success}");
print("dataVaalue: ${data["email"]}");
print("urlBelow: ${url}");
print("headersBelow: ${headers}");
});
}
}
}
}

Answer 1

A solution to your problem could be a static function inside a Drawer class. You could use this function in another file without initializing a new instance of a Drawer class by calling Drawer.function(). This function though can access only static variables of the parent class.
Also check this explanation: Class variables and methods - dart.dev
But:
Consider using top-level functions, instead of static methods, for common or widely used utilities and functionality.

Answer 2

You will need to create a function inside the calling class to call the Future function of another class. See the example below:
class ClassName {
Future<void> functionName {
something
}
}
class CallingClassName {
Final ClassName objName = ClassName();
void callingFunciton {
objName.functionName();
}
}

Answer 3

in main.dart write the future method globally (outside any widget or class):
Future<Database> initializeDatabase() async {
var databasesPath = await getDatabasesPath();
var path = join(databasesPath, "tafheemul_quran.db");
// Check if the database exists
var exists = await databaseExists(path);
if (!exists) {
// Should happen only the first time you launch your application
print("Creating new copy from asset");
// Make sure the parent directory exists
try {
await Directory(dirname(path)).create(recursive: true);
} catch (_) {}
// Copy from asset
ByteData data = await rootBundle.load(join("assets", "tafheemul_quran.db"));
List<int> bytes =
data.buffer.asUint8List(data.offsetInBytes, data.lengthInBytes);
// Write and flush the bytes written
await File(path).writeAsBytes(bytes, flush: true);
} else {
print("Opening existing database");
}
// open the database
var bomDataTable = await openDatabase(path, readOnly: true);
return bomDataTable;
}
then in Another dart, import the main.dart :
import 'package:flutter/material.dart';
import 'package:sqflite/sqflite.dart';
import 'main.dart';
then in that dart in any class, call the function :
class TokenExplActivity_Main extends State<TokenExplPassDataClass> {
//const TokenExplActivity_Main({Key? key}) : super(key: key);
String rowId = "";
String name = "";
String email = "";
String address = "";
Future<Database> get database async {
Database _database = await initializeDatabase();
if (_database == null) {
_database = await initializeDatabase();
}
return _database;
}
Actually the summary is, make the function globally and call the dart file in import first.