sqflite_preferences
sqflite preferences is an approach to simulate the sharedpreferences behaveir through sqflite library
https://github.com/ahmedkubur/sqflite_preferences
Usage
How to use
//import the library first
import 'package:sqflite_preferences/sqflite_preferences.dart';
//reference to our single class that manages the database
final dbHelper = DatabaseHelper.instance;
to initiate your database
initDatabase() async {
dbHelper.initDatabase('phoneNumber', 'INTEGER');
}
to add new or update bool value by key and value
setBoolValue()async{
await dbHelper.setBool('flag',true);
}
to get bool value by key
bool boolValue;
getBoolValue() async {
boolValue = await dbHelper.getBool('flag');
}
to add new or update int value by key and value
setIntValue()async{
await dbHelper.setInt('number',1);
}
to get int value by key
int intValue;
getIntValue()async{
intValue = await dbHelper.getInt('number');
}
to add new or update real value by key and value
setIntValue()async{
await dbHelper.setReal('real',1.555);
}
to get real by key
int intValue;
getIntValue()async{
intValue = await dbHelper.getReal('real');
}
to add new or update blob value by key and value
dynamic response = await get(url);
dynamic bytesFromPict = response.image.bodyBytes;
setBlobValue() async {
await dbHelper.setBlob('pic',bytesFromPic);
}
to get blob value by key
dynamic blobValue;
getBlobValue() async {
blobValue = await dbHelper.getBlob('pic');
}
// Example : Image.memory(blobValue),
to add new or update String value by key and value
setStringValue() async {
await dbHelper.setString('name','someone name');
}
to get String value by key
String stringValue;
getStringValue() async {
stringValue = await dbHelper.getString('name');
}
to get the number of raws by key
rowCount() async {
await dbHelper.queryRowCount('name');
}
to delete a saved data permenatly by key
deleteValue() async {
await dbHelper.delete('name');
}
Example
import 'package:dbhelper/dbHelper.dart';
import 'package:flutter/material.dart';
var dbHelper = DatabaseHelper.instance;
var value;
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
// This is the theme of your application.
//
// Try running your application with "flutter run". You'll see the
// application has a blue toolbar. Then, without quitting the app, try
// changing the primarySwatch below to Colors.green and then invoke
// "hot reload" (press "r" in the console where you ran "flutter run",
// or simply save your changes to "hot reload" in a Flutter IDE).
// Notice that the counter didn't reset back to zero; the application
// is not restarted.
primarySwatch: Colors.blue,
// This makes the visual density adapt to the platform that you run
// the app on. For desktop platforms, the controls will be smaller and
// closer together (more dense) than on mobile platforms.
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
// This widget is the home page of your application. It is stateful, meaning
// that it has a State object (defined below) that contains fields that affect
// how it looks.
// This class is the configuration for the state. It holds the values (in this
// case the title) provided by the parent (in this case the App widget) and
// used by the build method of the State. Fields in a Widget subclass are
// always marked "final".
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
void _incrementCounter() {
setState(() {
// This call to setState tells the Flutter framework that something has
// changed in this State, which causes it to rerun the build method below
// so that the display can reflect the updated values. If we changed
// _counter without calling setState(), then the build method would not be
// called again, and so nothing would appear to happen.
_counter++;
});
}
var textValue;
@override
Widget build(BuildContext context) {
// This method is rerun every time setState is called, for instance as done
// by the _incrementCounter method above.
//
// The Flutter framework has been optimized to make rerunning build methods
// fast, so that you can just rebuild anything that needs updating rather
// than having to individually change instances of widgets.
return Scaffold(
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
title: Text(widget.title),
),
body: Center(
// Center is a layout widget. It takes a single child and positions it
// in the middle of the parent.
child: Column(
// Column is also a layout widget. It takes a list of children and
// arranges them vertically. By default, it sizes itself to fit its
// children horizontally, and tries to be as tall as its parent.
//
// Invoke "debug painting" (press "p" in the console, choose the
// "Toggle Debug Paint" action from the Flutter Inspector in Android
// Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
// to see the wireframe for each widget.
//
// Column has various properties to control how it sizes itself and
// how it positions its children. Here we use mainAxisAlignment to
// center the children vertically; the main axis here is the vertical
// axis because Columns are vertical (the cross axis would be
// horizontal).
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Container(
padding: EdgeInsets.all(50),
child: TextField(
onChanged: (value) async {
textValue = value;
await dbHelper.setString('value', textValue);
},
),
),
RaisedButton(
child: Text("Get Value"),
onPressed: () async {
value = await dbHelper.getString('value');
},
),
RaisedButton(
child: Text("Go to next page"),
onPressed: () {
Navigator.of(context).push(
MaterialPageRoute(
fullscreenDialog: true,
builder: (BuildContext ctx) {
return Page2();
}),
);
},
),
],
),
),
);
}
}
class Page2 extends StatefulWidget {
@override
_Page2State createState() => _Page2State();
}
class _Page2State extends State<Page2> {
@override
void initState() {
super.initState();
}
@override
Widget build(BuildContext context) {
// var height = MediaQuery.of(context).size.height;
var width = MediaQuery.of(context).size.width;
return Scaffold(
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
// title: Text(widget.title),
),
body: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Center(
child: Container(
padding: EdgeInsets.all(30),
width: width,
child: FittedBox(
child: Text(
"$value",
style: TextStyle(color: Colors.black, fontSize: 30),
),
),
),
),
],
),
);
}
}