Dart DateTime.toIso8601String() throwing exception when inserting into SQFlite database - sql

Question

I am having trouble inserting a DateTime.toIso8601String() into a SQLite (SQFlite) database in Dart. The issue I am having is with a property_model class, who's only job is to interact with the database and hold data. I have an almost identical address_model class that works how I expect it, but I am having trouble with the property_model. Whenever I try to call the Property.insert() method, I get this error:
E/flutter: [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: Invalid argument: Instance of 'DateTime'
I don't have this issue with the very similar Address class though, and I am pretty stumped. Here are the property_model, address_model, and database files I am using (the database.dart file is a singleton that I use throughout the application).
property_model.dart
import 'package:flutter/material.dart';
import 'package:sqflite/sqflite.dart';
import 'package:villadex/model/database.dart' as db;
import 'package:villadex/model/address_model.dart';
class Property {
/// Constructors
Property({
required this.name,
required Address address,
required this.owner,
}) : _address = address,
_primaryKey = null,
_dateCreated = DateTime.now();
Property.existing(
{required this.name,
required Address address,
required this.owner,
required int? primaryKey,
required DateTime dateCreated})
: _address = address,
_primaryKey = primaryKey,
_dateCreated = dateCreated;
Property.fromJSON({required Map<String, dynamic> json})
: name = json['name'],
owner = json['owner'],
_address = Address.fromJson(json: json['location']),
_primaryKey = json['property_id'],
_dateCreated = DateTime.fromMillisecondsSinceEpoch(json['dateCreated']);
/// Data
String name;
String? owner;
final Address _address;
/*final List<Event> calendar;
final List<Expenditure> expenditures;
final List<Associate> associates;
final List<Earning> earnings;*/
final int? _primaryKey;
final DateTime _dateCreated;
///Methods
Future<void> insert() async {
String dateCreated = _dateCreated.toIso8601String().trim();
Map<String, dynamic> data = {
// SQFlite sets the primary key
'name': name,
'owner': owner,
'location': address.toJson(),
'dateCreated': dateCreated,
};
await db.DatabaseConnection.database.then((databaseConnection) => {
databaseConnection?.insert('properties', data,
conflictAlgorithm: ConflictAlgorithm.replace)
});
}
static Future<Property?> fetchById(int id) async {
String sql = "SELECT * FROM properties WHERE property_id = $id";
Future<List<Map<String, dynamic>>>? rawData;
await db.DatabaseConnection.database.then(
(databaseConnection) => {rawData = databaseConnection?.rawQuery(sql)});
return rawData?.then((data) {
return Property.fromJSON(json: data[0]);
});
}
/// Getters
Address get address => _address;
}
address_model.dart
import 'package:flutter/material.dart';
import 'package:villadex/model/database.dart' as db;
class Address {
/// Constructors
Address(
{required this.street1,
this.street2 = '',
required this.city,
this.state = '',
this.zip = '',
required this.country})
: _dateCreated = DateTime.now(),
_primaryKey = null,
_propertyId = null,
_associateId = null;
Address.existing({
required this.street1,
this.street2 = '',
required this.city,
this.state = '',
this.zip = '',
required this.country,
required DateTime dateCreated,
required int primaryKey,
int? propertyKey,
int? associateKey,
}) : _dateCreated = dateCreated,
_primaryKey = primaryKey,
_propertyId = propertyKey,
_associateId = associateKey;
Address.fromJson({required Map<String, dynamic> json})
: street1 = json['street1'],
street2 = json['street2'],
city = json['city'],
state = json['state'],
zip = json['zip'],
country = json['country'],
_primaryKey = json['address_id'],
_propertyId = json['property_id'],
_associateId = json['associate_id'],
_dateCreated = DateTime.parse(json['_dateCreated']);
/// Data
final String street1;
final String street2;
final String city;
final String state;
final String zip;
final String country;
final int? _primaryKey;
final int? _propertyId;
final int? _associateId;
final DateTime _dateCreated;
/// Methods
Future<void> insert() async {
Map<String, dynamic> data = {
// SQFlite sets the primaryKey
'property_id': _propertyId,
'associate_id': _associateId,
'dateCreated': _dateCreated.toIso8601String().trim(),
'street1': street1,
'street2': street2,
'city': city,
'zip': zip,
'country': country
};
await db.DatabaseConnection.database.then((databaseConnection) =>
{databaseConnection?.insert('addresses', data)});
}
// Returns an address by ID
static Future<Address?> fetchById(int id) async {
String sql = "SELECT * FROM addresses WHERE address_id = $id";
Future<List<Map<String, dynamic>>>? rawData;
await db.DatabaseConnection.database.then(
(databaseConnection) => {rawData = databaseConnection?.rawQuery(sql)});
return rawData?.then((data) {
return Address.fromJson(json: data[0]);
});
}
Map<String, dynamic> toJson() {
return {
'street1': street1,
'street2': street2,
'city': city,
'state': state,
'zip': zip,
'country': country,
'address_id': _primaryKey,
'property_id': _propertyId,
'associate_id': _associateId,
'dateCreated': _dateCreated
};
}
/// Getters
String get fullAddress =>
street1 +
" " +
street2 +
", " +
city +
" " +
state +
" " +
zip +
", " +
country;
DateTime get dateCreated => _dateCreated;
int get key => _primaryKey ?? 0;
/// Setters
}
database.dart
import 'package:path/path.dart';
import 'package:sqflite/sqflite.dart';
import 'package:path_provider/path_provider.dart';
import 'dart:async';
import 'package:villadex/model/property_model.dart';
class DatabaseConnection {
//static final DatabaseConnection instance = DatabaseConnection.init();
//DatabaseConnection._init();
/// Database variable
static Database? _database;
/// Getter for the database
static Future<Database?> get database async {
// If _database is null, set it equal to the return value of _initDB
_database ??= await _initDB('database3');
return _database;
}
/// Initialize database
static Future<Database?> _initDB(String dbname) async {
final dbPath = await getApplicationDocumentsDirectory();
final path = join(dbPath.toString(), dbname);
var dbInstance = await openDatabase(path, version: 1, onCreate: _createDatabase);
return dbInstance;
}
/// Create the database
static Future _createDatabase(Database database, int version) async {
Batch batch = database.batch();
/// CREATE PROPERTIES TABLE
batch.execute('''CREATE TABLE properties(
property_id INTEGER PRIMARY KEY,
dateCreated TEXT NOT NULL,
name TEXT NOT NULL,
location TEXT NOT NULL,
owner TEXT NOT NULL,
calendar TEXT,
expenditures TEXT,
associates TEXT,
earnings TEXT
);''');
/// CREATE EXPENDITURES TABLE
batch.execute('''CREATE TABLE expenditures(
expenditure_id INTEGER PRIMARY KEY,
property_id INTEGER NOT NULL,
dateCreated TEXT NOT NULL,
name TEXT NOT NULL,
amount REAL NOT NULL,
numberUnits INTEGER NOT NULL,
isPaid INTEGER NOT NULL,
description TEXT,
category TEXT,
date TEXT,
associates TEXT,
FOREIGN KEY (property_id)
REFERENCES properties(property_id)
);''');
/// CREATE EARNINGS TABLE
batch.execute(''' CREATE TABLE earnings(
earning_id INTEGER PRIMARY KEY,
property_id INTEGER NOT NULL,
dateCreated TEXT NOT NULL,
name TEXT NOT NULL,
amount REAL NOT NULL,
description TEXT,
category TEXT,
date TEXT,
associates TEXT,
FOREIGN KEY (property_id)
REFERENCES properties(property_id)
);''');
/// CREATE CATEGORIES TABLE
batch.execute(''' CREATE TABLE categories(
category_id INTEGER NOT NULL,
dateCreated TEXT NOT NULL,
name TEXT NOT NULL
);''');
/// CREATE ASSOCIATES TABLE
batch.execute(''' CREATE TABLE associates(
associate_id INTEGER PRIMARY KEY,
property_id INTEGER NOT NULL,
dateCreated TEXT NOT NULL,
name TEXT NOT NULL,
contact TEXT,
role TEXT,
payments TEXT,
FOREIGN KEY (property_id)
REFERENCES properties (property_id)
);''');
/// CREATE CONTACTS TABLE
batch.execute(''' CREATE TABLE contact (
associate_id INTEGER NOT NULL,
phoneNumber TEXT,
email TEXT,
FOREIGN KEY (associate_id)
REFERENCES associates (associate_id)
);''');
/// CREATE ADDRESSES TABLE
batch.execute(''' CREATE TABLE addresses (
address_id INTEGER PRIMARY KEY,
property_id INTEGER,
associate_id INTEGER,
dateCreated TEXT NOT NULL,
street1 TEXT NOT NULL,
street2 TEXT,
city TEXT NOT NULL,
zip TEXT,
state TEXT,
country TEXT,
FOREIGN KEY (property_id)
REFERENCES properties (property_id),
FOREIGN KEY (associate_id)
REFERENCES associates (associate_id)
);''');
/// CREATE EVENT TABLE
batch.execute(''' CREATE TABLE event (
event_id INTEGER PRIMARY KEY,
property_id INTEGER NOT NULL,
dateCreated TEXT NOT NULL,
name TEXT NOT NULL,
description TEXT,
address TEXT,
associates TEXT,
expenditures TEXT,
earnings TEXT,
FOREIGN KEY (property_id)
REFERENCES properties (property_id)
);''');
batch.commit();
}
Future close() async {
_database?.close;
}
}
Thank you for any help!

Answer 1

I figured it out. The address object within my property object did not turn its DateTime object into a string during the address.toJson() method, which is why it was giving me that error.