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create pdf file in flutter

dependencies:
  pdf: ^1.9.0

CreatePdf.dart 

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:image/image.dart';
import 'package:movements/Utils.dart';
import 'package:path_provider/path_provider.dart';
import 'package:pdf/pdf.dart';
import 'package:pdf/widgets.dart' as pw;


class CreatePdf extends StatefulWidget {
  @override  _CreatePdfState createState() => _CreatePdfState();
}

class _CreatePdfState extends State<CreatePdf> {
  @override  void initState() {
    // TODO: implement initState    super.initState();
  }

  @override  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Create PDF"),
        elevation: .1,
      ),
      body: Center(
        child: Container(
          child: FlatButton(
              onPressed: () {
                createPdf();
              },
              child: Text("Create PDF")),
        ),
      ),
    );
  }


  Future createPdf() async {
    final pdf = pw.Document();


    pdf.addPage(pw.Page(
        pageFormat: PdfPageFormat.a4,
        build: (pw.Context context) {
          return pw.Center(
            child: pw.Text("Hello World"),
          ); // Center        }));

    var number = Utils.getRandomNumber(4);
    final output =
        await getExternalStorageDirectory(); // use the [path_provider (https://pub.dartlang.org/packages/path_provider) library:    final file = File("${output.path}/example" + number.toString() + ".pdf");
    await file.writeAsBytes(pdf.save());
  }
}

Flutter Keystore generate command

Go to  Java installation folder bin,

Now use the below keytool command to generate keystore file. Go to the java bin path in command line tool and use below command


keytool -genkey -v -keystore "D:/AppkeyStore.jks" -keyalg RSA -keysize 2048 -validity 10000 -alias "AppAliasName"


To check expiration of the jsk file.

keytool -list -v -keystore AppkeyStore.jks

keytool -importkeystore -srckeystore /Users/pratapkumar/Desktop/shary/sharyAppkeyStore.jks -destkeystore /Users/pratapkumar/Desktop/shary/sharyAppkeyStore.jks -deststoretype pkcs12

Flutter GPS Location

In this tutorial , we try to fetch phone GPS Location.

I used this library in pubspec.yaml file under dependencies

dependencies:
  location: ^2.3.5

Android #

In order to use this plugin in Android, you have to add this permission in AndroidManifest.xml :
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Permission check for Android 6+ was added.
iOS #
And to use it in iOS, you have to add this permission in Info.plist :
NSLocationWhenInUseUsageDescription
NSLocationAlwaysUsageDescription
Warning: there is a currently a bug in iOS simulator in which you have to manually select a Location several in order for the Simulator to actually send data. Please keep that in mind when testing in iOS simulator.

main.dart

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import 'package:flutter/material.dart'; import 'package:flutter_app_sample/GetLocationPage.dart'; 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 GPS', theme: ThemeData( primarySwatch: Colors.blue, ), home: GetLocationPage(), ); } }

GetLocationPage.dart

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import 'package:flutter/material.dart'; import 'package:location/location.dart'; class GetLocationPage extends StatefulWidget { @override _GetLocationPageState createState() => _GetLocationPageState(); } class _GetLocationPageState extends State<GetLocationPage> { LocationData _currentLocation; Location _locationService = new Location(); @override void initState() { // TODO: implement initState super.initState(); _getLocation().then((value) { setState(() { _currentLocation = value; }); }); } @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar(), body: Center( child: Column( mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[ _currentLocation == null ? CircularProgressIndicator() : Text("Location:" + _currentLocation.latitude.toString() + " " + _currentLocation.longitude.toString()), Padding( padding: const EdgeInsets.all(8.0), child: RaisedButton( onPressed: () { _getLocation().then((value) { setState(() { _currentLocation = value; }); }); }, color: Colors.blue, child: Text( "Get Location", style: TextStyle(color: Colors.white), ), ), ), ], ), ), ); } Future<LocationData> _getLocation() async { LocationData currentLocation; try { currentLocation = await _locationService.getLocation(); } catch (e) { currentLocation = null; } return currentLocation; } }

Flutter Infinite ListView using Webservice

In this tutorial, we will see how to implement Infinite ListView in Flutter using webservice.

Here is the reference link i used most of the code but i used webservice in this tutorial.

Thanks to author of the tutorial
https://marcinszalek.pl/flutter/infinite-dynamic-listview/


Now Let see using this webservice
https://api.randomuser.me/?page=1&results=20&seed=abc

Here page number increments after scroll reaches the end.

Demo:
=======

main.dart
==========

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import 'package:akeepo/randomuser_infinitelist.dart'; import 'package:flutter/material.dart'; void main() => runApp(MyApp()); class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( title: 'Flutter', debugShowCheckedModeBanner: false, theme: ThemeData( primarySwatch: Colors.blue, ), home: InfiniteUsersList(), ); } }

randomuser_infinitelist.dart
=============================

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import 'dart:async'; import 'dart:convert'; import 'package:flutter/material.dart'; import 'package:http/http.dart' as http; class InfiniteUsersList extends StatefulWidget { static String tag = 'users-page'; @override State<StatefulWidget> createState() { return new _InfiniteUsersListState(); } } class _InfiniteUsersListState extends State<InfiniteUsersList> { List<User> users = new List<User>(); ScrollController _scrollController = new ScrollController(); bool isPerformingRequest = false; int pageNumber = 0; @override void initState() { super.initState(); // Loading initial data or first request to get the data _getMoreData(); // Loading data after scroll reaches end of the list _scrollController.addListener(() { if (_scrollController.position.pixels == _scrollController.position.maxScrollExtent) { _getMoreData(); } }); } // to show progressbar while loading data in background Widget _buildProgressIndicator() { return new Padding( padding: const EdgeInsets.all(8.0), child: new Center( child: new Opacity( opacity: isPerformingRequest ? 1.0 : 0.0, child: new CircularProgressIndicator(), ), ), ); } @override void dispose() { _scrollController.dispose(); super.dispose(); } // Webservice request to load 20 users data using paging Future<List<User>> _getUsers() async { List<User> users = new List<User>(); setState(() { pageNumber++; }); String url = "https://api.randomuser.me/?page=$pageNumber&results=20&seed=abc"; print(url); var response = await http.get(url); var jsonData = json.decode(response.body); print(jsonData); var usersData = jsonData["results"]; for (var user in usersData) { User newUser = User(user["name"]["first"] + user["name"]["last"], user["email"], user["picture"]["large"], user["phone"]); users.add(newUser); } return users; } _getMoreData() async { if (!isPerformingRequest) { setState(() { isPerformingRequest = true; }); List<User> newEntries = await _getUsers(); //returns empty list if (newEntries.isEmpty) { double edge = 50.0; double offsetFromBottom = _scrollController.position.maxScrollExtent - _scrollController.position.pixels; if (offsetFromBottom < edge) { _scrollController.animateTo( _scrollController.offset - (edge - offsetFromBottom), duration: new Duration(milliseconds: 500), curve: Curves.easeOut); } } setState(() { users.addAll(newEntries); isPerformingRequest = false; }); } } Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text('Users', style: TextStyle(color: Colors.white, fontWeight: FontWeight.bold))), body: Container( child: ListView.builder( shrinkWrap: true, controller: _scrollController, itemCount: users.length + 1, itemBuilder: (BuildContext context, int index) { if (index == users.length) { return _buildProgressIndicator(); } else { return ListTile( onTap: () { Navigator.push( context, new MaterialPageRoute( builder: (context) => UserDetailPage(users[index]))); }, title: Text(users[index].fullName), subtitle: Text(users[index].mobileNumber), leading: CircleAvatar( backgroundImage: NetworkImage(users[index].imageUrl)), ); } })), ); } } class User { final String fullName; final String email; final String imageUrl; final String mobileNumber; User(this.fullName, this.email, this.imageUrl, this.mobileNumber); } // User Detail Page class UserDetailPage extends StatelessWidget { final User user; UserDetailPage(this.user); @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text("User Details"), ), body: Center( child: Text( user.fullName, style: TextStyle(fontSize: 35.0), ), ), ); } }

Git Commands

Download git
https://git-scm.com/

if you want to add your project to bitbucket or github. you can use the following commands

Step 1:
Right Click-> Git Bash Here or go to the Project folder if you are not using git GUI tools

Step 2:
Type git init (For initializing git).

Step 3:
Type git add -A (Get all files in the staging area).

Step 4:
Type git commit -m "First Commit"(Commit Changes)

Step 5:
Type git remote add origin https://..bitbucket.org/../ABC.git (Your repo URL)

Step 6:
Type git push -f origin master(your branch name)

Flutter Navigation Drawer Example

main.dart

=========

import 'package:flutter/material.dart';
import 'package:akeepo/navdrawer.dart';
void main() => runApp(MyApp());

class MyApp extends StatelessWidget {


  @override  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        primarySwatch: Colors.blue,

      ),
      home: NavDrawer(),

    );
  }
}

navdrawer.dart

================

import 'package:flutter/material.dart';

class NavDrawer extends StatefulWidget {
  @override  _NavDrawerState createState() => _NavDrawerState();
}

class _NavDrawerState extends State<NavDrawer> {
  @override  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("Nav Drawer")),
      drawer: new Drawer(
        child: new ListView(
          children: <Widget>[
            new UserAccountsDrawerHeader(
              accountName: new Text("Pratap Kumar"),
              accountEmail: new Text("kprathap23@gmail.com"),
              decoration: new BoxDecoration(
                image: new DecorationImage(
                  image: new ExactAssetImage('assets/images/lake.jpeg'),
                  fit: BoxFit.cover,
                ),
              ),
              currentAccountPicture: CircleAvatar(
                  backgroundImage: NetworkImage(
                      "https://randomuser.me/api/portraits/men/46.jpg")),
            ),
            new ListTile(
                leading: Icon(Icons.library_music),
                title: new Text("Music"),
                onTap: () {
                  Navigator.pop(context);
                }),
            new ListTile(
                leading: Icon(Icons.movie),
                title: new Text("Movies"),
                onTap: () {
                  Navigator.pop(context);
                }),
            new ListTile(
                leading: Icon(Icons.shopping_cart),
                title: new Text("Shopping"),
                onTap: () {
                  Navigator.pop(context);
                }),
            new ListTile(
                leading: Icon(Icons.apps),
                title: new Text("Apps"),
                onTap: () {
                  Navigator.pop(context);
                }),
            new ListTile(
                leading: Icon(Icons.dashboard),
                title: new Text("Docs"),
                onTap: () {
                  Navigator.pop(context);
                }),
            new ListTile(
                leading: Icon(Icons.settings),
                title: new Text("Settings"),
                onTap: () {
                  Navigator.pop(context);
                }),
            new Divider(),
            new ListTile(
                leading: Icon(Icons.info),
                title: new Text("About"),
                onTap: () {
                  Navigator.pop(context);
                }),
            new ListTile(
                leading: Icon(Icons.power_settings_new),
                title: new Text("Logout"),
                onTap: () {
                  Navigator.pop(context);
                }),
          ],
        ),
      ),
    );
  }
}