Ggtcf

I used SQLite for the cache. Everything is working well. But I don't know how to display value from this promise? (display() returns Future<List<Token>>)

What I want is properly something like var value = display().refreshToken

print statement printing List values

print(await display());

Database.dart

 // Open the database and store the reference
import 'dart:async';

import 'package:path/path.dart';
import 'package:reborn_next_job02/models/Token.dart';
import 'package:sqflite/sqflite.dart';

databaseToken(
 String tokenModel, String refreshTokenModel, String method) async 
 final database = openDatabase(
 join(await getDatabasesPath(), 'tokenDB.db'),
 onCreate: (db, version) 
 return db.execute(
 "CREATE TABLE tokenTable(id INTEGER PRIMARY KEY, token TEXT, refreshToken TEXT)",
 );
 ,
 version: 1,
 );

 Future<void> insert(Token token) async 
 final Database db = await database;
 await db.insert(
 'tokenTable',
 token.toMap(),
 //same use insert multiple times using ConfiictAlgorithm
 conflictAlgorithm: ConflictAlgorithm.replace,
 );
 

 Future<List<Token>> display() async 
 final Database db = await database;
 final List<Map<String, dynamic>> maps = await db.query('tokenTable');

 return List.generate(maps.length, (i) 
 return Token(
 id: maps[i]['id'],
 token: maps[i]['token'],
 refreshToken: maps[i]['refreshToken'],
 );
 );
 

 Future<void> update(Token token) async 
 final db = await database;

 await db.update(
 'tokenTable',
 token.toMap(),
 where: "id = ?",
 whereArgs: [token.id],
 );
 

 Future<void> delete(int id) async 
 final db = await database;

 await db.delete(
 'tokenTable',
 where: "id = ?",
 whereArgs: [id],
 );
 


 if (method == "insert") 
 var token = Token(
 id: 1,
 token: tokenModel,
 refreshToken: refreshTokenModel,
 );
 await insert(token);
 print(await display());
 else if (method == "update") 
 var token = Token(
 id: 1,
 token: tokenModel,
 refreshToken: refreshTokenModel,
 );
 await update(token);
 print(await display());
 

Model.dart

class Token 
 int id;
 String token;
 String refreshToken;

 Token(this.id,this.token, this.refreshToken);

 factory Token.fromJson(Map<String, dynamic> json)
 return Token(
 id: json['id'],
 token:json['token'],
 refreshToken: json['refreshToken']
 );
 
 Map<String, dynamic> toMap() 
 return 
 'id': id,
 'token': token,
 'refreshToken': refreshToken,
 ;
 

 @override
 String toString() 
 return 'Tokenid: $id, token: $token, refreshToken: $refreshToken';
 

You can get it with
print((await display())?.elementAt(0)?.refreshToken);

display() returns a future of list, so you have to wrap (await display()) before doing list manipulation, such as get an element from a list. list[0] is equivalent to list.elementAt(0), but list.elementAt(0)? is null-safe and out-of-bound-safe.