Google Maps and Geolocation in Flutter

Working with a user’s location is a common task that many apps require, yet the steps to implement a well working solution in an app is often confusing and has too much boilerplate required to set up. Most Flutter packages abstract away most or all of the boilerplate required and directly give users the most optimised solution and less hassle to deal with. Often this means some fine grained control is lost through abstraction, but most times it is not needed anyway.

You can look through a tutorial for implementing location in native android to see the immense and often not needed amount of information presented to app developers who simply want the user’s location or want to track it.

Today, we’ll look through implementing getting location, location tracking and geocoding in Flutter for both Android and iOS using two different plugins which give us a varied amount of control over the underlying APIs and then see the implementation of location with maps where we’ll track a user using a marker on a map.

Let’s get started.

Plugin 1: ‘location’

The ‘location’ plugin is the simplest way to get and track a user’s location without the hassle of any boilerplate code.

Setting up is simple enough:

1. Add plugin to the pubspec.yaml

dependencies:
  location: ^1.4.1

2. Add a permission to Android Manifest:

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

3. Add permissions to iOS Info.plist

<key>NSLocationAlwaysUsageDescription</key>
<string>Needed to access location</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>Needed to access location</string>

And you’re done.

In Android 6.0+, we need to ask access to location in runtime, which this package handles on its own.

Getting a one-time location

It allows us to get two things:

1. A one-time location of the user
2. A stream allowing us to listen to the location of the user.

Let’s create a simple app which gets the one-time location of the user like above.

Like we discussed, this package does not need much setup and the code is rather straightforward.

First, simply initialise a Location object.

var location = new Location();

location is not the location of the user itself but a class that helps us get it.

The location is returned as a map with keys like “latitude”, “longitude”, etc.

Map<String, double> userLocation;

And finally, getting the location is as simple as:

userLocation = await location.getLocation();

That’s it.

For the complete code:

class GetLocationPage extends StatefulWidget {
  @override
  _GetLocationPageState createState() => _GetLocationPageState();
}

class _GetLocationPageState extends State<GetLocationPage> {

  var location = new Location();

  Map<String, double> userLocation;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            userLocation == null
                ? CircularProgressIndicator()
                : Text("Location:" +
                    userLocation["latitude"].toString() +
                    " " +
                    userLocation["longitude"].toString()),
            Padding(
              padding: const EdgeInsets.all(8.0),
              child: RaisedButton(
                onPressed: () {
                  _getLocation().then((value) {
                    setState(() {
                      userLocation = value;
                    });
                  });
                },
                color: Colors.blue,
                child: Text("Get Location", style: TextStyle(color: Colors.white),),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Future<Map<String, double>> _getLocation() async {
    var currentLocation = <String, double>{};
    try {
      currentLocation = await location.getLocation();
    } catch (e) {
      currentLocation = null;
    }
    return currentLocation;
  }
}

GetLocationPage.dart

Here, we get the latitude and longitude. Other factors available are:

  currentLocation["latitude"];
  currentLocation["longitude"];
  currentLocation["accuracy"];
  currentLocation["altitude"];
  currentLocation["speed"];
  currentLocation["speed_accuracy"]; //Not for iOS

Listening to location updates

Listening to location updates is not that different from getting location, we simply use a stream object provided by the plugin to listen to updates.

location.onLocationChanged().listen((Map<String,double> currentLocation) {
  print(currentLocation["latitude"]);
  print(currentLocation["longitude"]);
  print(currentLocation["accuracy"]);
  print(currentLocation["altitude"]);
  print(currentLocation["speed"]);
  print(currentLocation["speed_accuracy"]); 
});

An example page of this would be:

import 'package:flutter/material.dart';
import 'package:location/location.dart';

class ListenPage extends StatefulWidget {
  @override
  _ListenPageState createState() => _ListenPageState();
}

class _ListenPageState extends State<ListenPage> {

  Location location = Location();

  Map<String, double> currentLocation;

  @override
  void initState() {
    // TODO: implement initState
    super.initState();
    location.onLocationChanged().listen((value) {
      setState(() {
        currentLocation = value;
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Column(
        children: <Widget>[
          currentLocation == null
              ? CircularProgressIndicator()
              : Text("Location:" + currentLocation["latitude"].toString() + " " + currentLocation["longitude"].toString()),
        ],
      ),
    );
  }
}

ListenPage.dart

Which gives a similar page to the one we made with the first example, but this time, we listen for location.

This plugin was a simple one to use without much setup or control and was straightforward in use and intention. Next, we’ll see another which gives more control over the APIs involved and also allows for geocoding.

Plugin 2: ‘geolocator’

Setup

The setup for this plugin is more or less the same as the location. If you plan to use coarse location as well, add

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

to AndroidManifest.xml .

First, we will do the same two tasks with this plugin, which is more or less the same:

Get location once

Use the Geolocator object instead of Location and instead of a Map<String,double> , we get back a Position object.

Geolocator geolocator = Geolocator();

Position userLocation;

And we do this to take location:

currentLocation = await geolocator.getCurrentPosition(
    desiredAccuracy: LocationAccuracy.best);

Here, we can also set the location accuracy depending on the accuracy we need.

import 'package:flutter/material.dart';
import 'package:geolocator/geolocator.dart';
import 'dart:async';

class GeoListenPage extends StatefulWidget {
  @override
  _GeoListenPageState createState() => _GeoListenPageState();
}

class _GeoListenPageState extends State<GeoListenPage> {
  Geolocator geolocator = Geolocator();

  Position userLocation;

  @override
  void initState() {
    // TODO: implement initState
    super.initState();
    _getLocation().then((position) {
      userLocation = position;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            userLocation == null
                ? CircularProgressIndicator()
                : Text("Location:" +
                    userLocation.latitude.toString() +
                    " " +
                    userLocation.longitude.toString()),
            Padding(
              padding: const EdgeInsets.all(8.0),
              child: RaisedButton(
                onPressed: () {
                  _getLocation().then((value) {
                    setState(() {
                      userLocation = value;
                    });
                  });
                },
                color: Colors.blue,
                child: Text(
                  "Get Location",
                  style: TextStyle(color: Colors.white),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Future<Position> _getLocation() async {
    var currentLocation;
    try {
      currentLocation = await geolocator.getCurrentPosition(
          desiredAccuracy: LocationAccuracy.best);
    } catch (e) {
      currentLocation = null;
    }
    return currentLocation;
  }
}

GeolocatorListenPage.dart

Get Location Updates

Updates are similar to the ‘location’ package but with enhanced options.

geolocator.getPositionStream().listen((position) {
  // Do something here
});

We can set the accuracy, time interval between updates, whether we want to force usage of Android location manager, etc.

geolocator
    .getPositionStream(LocationOptions(
        accuracy: LocationAccuracy.best, timeInterval: 1000))
    .listen((position) {
  // Do something here
});

Working with Geocoding

Geocoding is essentially the process of getting physical map co-ordinates and details for an address.

List<Placemark> placemark = await Geolocator().placemarkFromAddress("Gronausestraat 710, Enschede");

You can get all the details about the place as:

print(placemark[0].country);
print(placemark[0].position);
print(placemark[0].locality);
print(placemark[0].administrativeArea);
print(placemark[0].postalCode);
print(placemark[0].name);
print(placemark[0].subAdministratieArea);
print(placemark[0].isoCountryCode);
print(placemark[0].subLocality);
print(placemark[0].subThoroughfare);
print(placemark[0].thoroughfare);

We can also get the details of a place from the coordinates:

List<Placemark> placemark = await Geolocator().placemarkFromCoordinates(52.2165157, 6.9437819);

Getting the distance between coordinates

This plugin also allows us to calculate the distance between two coordinates as:

double distanceInMeters = await Geolocator().distanceBetween(52.2165157, 6.9437819, 52.3546274, 4.8285838);

Integrating location updates with Google Maps

To integrate Google Maps with location updates, we need to use the google_maps_flutter package and your choice of location plugin.

Let’s just use the ‘location’ package for now.

A precursor to this part is my “Exploring Google Maps in Flutter” article and I highly recommend you use it to set up Maps in your app.

Exploring Google Maps in Flutter

To integrate maps with location tracking, we simply need to use both the plugins in conjunction.

Let’s move a marker as the user changes location.

First, we create our MapController and Location objects to manipulate maps and location. (Assign mapController when map is initialised, as given in the upper article)

GoogleMapController mapController;
Location location = Location();

Next, we add a marker to store the current marker:

Marker marker;

Now, we listen to location updates.

location.onLocationChanged().listen((location) async {
  // Do something here
});

This is how we will move the marker when location is updated:

1. Remove the current marker if not null as there is now a new location it needs to be at.
2. Add marker at latitude and longitude.
3. Move camera to new marker location and set other characteristics like zoom, bearing and tilt. (Details about this given in GMaps article)

location.onLocationChanged().listen((location) async {
  // Step 1
  if(marker != null) {
    mapController.removeMarker(marker);
  }
  // Step 2
  marker = await mapController?.addMarker(MarkerOptions(
    position: LatLng(location["latitude"], location["longitude"]),
  ));
  //Step 3
  mapController?.moveCamera(
    CameraUpdate.newCameraPosition(
      CameraPosition(
        target: LatLng(
          location["latitude"],
          location["longitude"],
        ),
        zoom: 20.0,
      ),
    ),
  );
});

And now the marker will update location when the user moves!

Here’s the complete demo page code:

class GoogleMapsDemo extends StatefulWidget {
  @override
  _GoogleMapsDemoState createState() => _GoogleMapsDemoState();
}

class _GoogleMapsDemoState extends State<GoogleMapsDemo> {
  GoogleMapController mapController;
  Location location = Location();

  Marker marker;

  @override
  void initState() {
    super.initState();
    location.onLocationChanged().listen((location) async {
      if(marker != null) {
        mapController.removeMarker(marker);
      }
      marker = await mapController?.addMarker(MarkerOptions(
        position: LatLng(location["latitude"], location["longitude"]),
      ));
      mapController?.moveCamera(
        CameraUpdate.newCameraPosition(
          CameraPosition(
            target: LatLng(
              location["latitude"],
              location["longitude"],
            ),
            zoom: 20.0,
          ),
        ),
      );
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Column(
        children: <Widget>[
          Container(
            height: MediaQuery.of(context).size.height,
            width: MediaQuery.of(context).size.width,
            child: GoogleMap(
              onMapCreated: (GoogleMapController controller) {
                mapController = controller;
              },
              options: GoogleMapOptions(
                cameraPosition: CameraPosition(
                  target: LatLng(37.4219999, -122.0862462),
                ),
                myLocationEnabled: true,
              ),
            ),
          ),
        ],
      ),
    );
  }
}

GMapsPlusLocation.dart

That’s it for this article! I hope you enjoyed it, and leave a few claps if you did. Follow me for more Flutter articles and comment for any feedback you might have about this article.

#flutter #programming

What is GEEK

Buddha Community

Google's Flutter 1.20 stable announced with new features - Navoki

Flutter Google cross-platform UI framework has released a new version 1.20 stable.

Flutter is Google’s UI framework to make apps for Android, iOS, Web, Windows, Mac, Linux, and Fuchsia OS. Since the last 2 years, the flutter Framework has already achieved popularity among mobile developers to develop Android and iOS apps. In the last few releases, Flutter also added the support of making web applications and desktop applications.

Last month they introduced the support of the Linux desktop app that can be distributed through Canonical Snap Store(Snapcraft), this enables the developers to publish there Linux desktop app for their users and publish on Snap Store.  If you want to learn how to Publish Flutter Desktop app in Snap Store that here is the tutorial.

Flutter 1.20 Framework is built on Google’s made Dart programming language that is a cross-platform language providing native performance, new UI widgets, and other more features for the developer usage.

Here are the few key points of this release:

Performance improvements for Flutter and Dart

In this release, they have got multiple performance improvements in the Dart language itself. A new improvement is to reduce the app size in the release versions of the app. Another performance improvement is to reduce junk in the display of app animation by using the warm-up phase.

If your app is junk information during the first run then the Skia Shading Language shader provides for pre-compilation as part of your app’s build. This can speed it up by more than 2x.

Added a better support of mouse cursors for web and desktop flutter app,. Now many widgets will show cursor on top of them or you can specify the type of supported cursor you want.

Autofill for mobile text fields

Autofill was already supported in native applications now its been added to the Flutter SDK. Now prefilled information stored by your OS can be used for autofill in the application. This feature will be available soon on the flutter web.

A new widget for interaction

InteractiveViewer is a new widget design for common interactions in your app like pan, zoom drag and drop for resizing the widget. Informations on this you can check more on this API documentation where you can try this widget on the DartPad. In this release, drag-drop has more features added like you can know precisely where the drop happened and get the position.

Updated Material Slider, RangeSlider, TimePicker, and DatePicker

In this new release, there are many pre-existing widgets that were updated to match the latest material guidelines, these updates include better interaction with Slider and RangeSlider, DatePicker with support for date range and time picker with the new style.

New pubspec.yaml format

Other than these widget updates there is some update within the project also like in pubspec.yaml file format. If you are a flutter plugin publisher then your old pubspec.yaml  is no longer supported to publish a plugin as the older format does not specify for which platform plugin you are making. All existing plugin will continue to work with flutter apps but you should make a plugin update as soon as possible.

Preview of embedded Dart DevTools in Visual Studio Code

Visual Studio code flutter extension got an update in this release. You get a preview of new features where you can analyze that Dev tools in your coding workspace. Enable this feature in your vs code by _dart.previewEmbeddedDevTools_setting. Dart DevTools menu you can choose your favorite page embed on your code workspace.

Network tracking

The updated the Dev tools comes with the network page that enables network profiling. You can track the timings and other information like status and content type of your** network calls** within your app. You can also monitor gRPC traffic.

Generate type-safe platform channels for platform interop

Pigeon is a command-line tool that will generate types of safe platform channels without adding additional dependencies. With this instead of manually matching method strings on platform channel and serializing arguments, you can invoke native class and pass nonprimitive data objects by directly calling the Dartmethod.

There is still a long list of updates in the new version of Flutter 1.2 that we cannot cover in this blog. You can get more details you can visit the official site to know more. Also, you can subscribe to the Navoki newsletter to get updates on these features and upcoming new updates and lessons. In upcoming new versions, we might see more new features and improvements.

You can get more free Flutter tutorials you can follow these courses:

• Setup Flutter Desktop on Windows, Linux, MacOS using VSCode and Build – Flutter Tutorial
• Flutter Desktop Linux app | Build and Publish on Snapcraft Store
• Firebase Local Emulator Suite in Flutter

#dart #developers #flutter #app developed #dart devtools in visual studio code #firebase local emulator suite in flutter #flutter autofill #flutter date picker #flutter desktop linux app build and publish on snapcraft store #flutter pigeon #flutter range slider #flutter slider #flutter time picker #flutter tutorial #flutter widget #google flutter #linux #navoki #pubspec format #setup flutter desktop on windows

What is Flutter and why you should learn it?

Flutter is an open-source UI toolkit for mobile developers, so they can use it to build native-looking** Android and iOS** applications from the same code base for both platforms. Flutter is also working to make Flutter apps for Web, PWA (progressive Web-App) and Desktop platform (Windows,macOS,Linux).

Flutter was officially released in December 2018. Since then, it has gone a much stronger flutter community.

There has been much increase in flutter developers, flutter packages, youtube tutorials, blogs, flutter examples apps, official and private events, and more. Flutter is now on top software repos based and trending on GitHub.

Flutter meaning?

What is Flutter? this question comes to many new developer’s mind.

Flutter means flying wings quickly, and lightly but obviously, this doesn’t apply in our SDK.

So Flutter was one of the companies that were acquired by **Google **for around $40 million. That company was based on providing gesture detection and recognition from a standard webcam. But later when the Flutter was going to release in alpha version for developer it’s name was Sky, but since Google already owned Flutter name, so they rename it to Flutter.

Where Flutter is used?

Flutter is used in many startup companies nowadays, and even some MNCs are also adopting Flutter as a mobile development framework. Many top famous companies are using their apps in Flutter. Some of them here are

Dream11

NuBank

Reflectly app

Abbey Road Studios

and many more other apps. Mobile development companies also adopted Flutter as a service for their clients. Even I was one of them who developed flutter apps as a freelancer and later as an IT company for mobile apps.

#dart #flutter #uncategorized #flutter framework #flutter jobs #flutter language #flutter meaning #flutter meaning in hindi #google flutter #how does flutter work #what is flutter

The Ultimate Guide To Tik Tok Clone App With Firebase - Ep 2

The Ultimate Guide To Tik Tok Clone App With Firebase - Ep 2
In this video, I'm going to show you how to make a Cool Tik Tok App a new Instagram using Flutter,firebase and visual studio code.

In this tutorial, you will learn how to Upload a Profile Pic to Firestore Data Storage.

🚀 Nice, clean and modern TikTok Clone #App #UI made in #Flutter⚠️

Starter Project : https://github.com/Punithraaj/Flutter_Tik_Tok_Clone_App/tree/Episode1

► Timestamps 
0:00 Intro 0:20 
Upload Profile Screen 
16:35 Image Picker
20:06 Image Cropper 
24:25 Firestore Data Storage Configuration.

⚠️ IMPORTANT: If you want to learn, I strongly advise you to watch the video at a slow speed and try to follow the code and understand what is done, without having to copy the code, and then download it from GitHub.

► Social Media 
GitHub: https://github.com/Punithraaj/Flutter_Tik_Tok_Clone_App.git
LinkedIn: https://www.linkedin.com/in/roaring-r...
Twitter: https://twitter.com/roaringraaj
Facebook: https://www.facebook.com/flutterdartacademy

► Previous Episode : https://youtu.be/QnL3fr-XpC4
► Playlist: https://youtube.com/playlist?list=PL6vcAuTKAaYe_9KQRsxTsFFSx78g1OluK

I hope you liked it, and don't forget to like,comment, subscribe, share this video with your friends, and star the repository on GitHub!
⭐️ Thanks for watching the video and for more updates don't forget to click on the notification. 
⭐️Please comment your suggestion for my improvement. 
⭐️Remember to like, subscribe, share this video, and star the repo on Github :)

Hope you enjoyed this video!
If you loved it, you can Buy me a coffee : https://www.buymeacoffee.com/roaringraaj

LIKE & SHARE & ACTIVATE THE BELL Thanks For Watching :-)
 
https://youtu.be/F_GgZVD4sDk

#flutter tutorial - tiktok clone with firebase #flutter challenge @tiktokclone #fluttertutorial firebase #flutter firebase #flutter pageview #morioh #flutter

Flutter Hotel Booking UI - Book your Stay At A New Hotel With Flutter - Ep1

https://youtu.be/-tHUmjIkGJ4
Flutter Hotel Booking UI - Book your Stay At A New Hotel With Flutter - Ep1
#flutter #fluttertravelapp #hotelbookingui #flutter ui design 

In this video, I'm going to show you how to make a Cool Hotel Booking App using Flutter and visual studio code. 

In this tutorial, you will learn how to create a Splash Screen and Introduction Screen, how to implement a SmoothPageIndicator in Flutter. 

🚀 Nice, clean and modern Hotel Booking #App #UI made in #Flutter 

⚠️ IMPORTANT: If you want to learn, I strongly advise you to watch the video at a slow speed and try to follow the code and understand what is done, without having to copy the code, and then download it from GitHub. 

► Social Media 

    GitHub: https://github.com/Punithraaj 

    LinkedIn: https://www.linkedin.com/in/roaring-r...

    Twitter: https://twitter.com/roaringraaj

    Facebook: https://www.facebook.com/flutterdartacademy

I hope you liked it, and don't forget to like,comment, subscribe, share this video with your friends, and star the repository on GitHub! 

⭐️ Thanks for watching the video and for more updates don't forget to click on the notification.⭐️Please comment your suggestion for my improvement. ⭐️Remember to like, subscribe, share this video, and star the repo on Github :)Hope you enjoyed this video! If you loved it, you can Buy me a coffee : https://www.buymeacoffee.com/roaringraaj

#flutter riverpod #flutter travel app #appointment app flutter #morioh

Adobe XD plugin for Flutter with CodePen Tutorial

Recently Adobe XD releases a new version of the plugin that you can use to export designs directly into flutter widgets or screens. Yes, you read it right, now you can make and export your favorite design in Adobe XD and export all the design in the widget form or as a full-screen design, this can save you a lot of time required in designing.

What we will do?
I will make a simple design of a dialogue box with a card design with text over it as shown below. After you complete this exercise you can experiment with the UI. You can make your own components or import UI kits available with the Adobe XD.

#developers #flutter #adobe xd design export to flutter #adobe xd flutter code #adobe xd flutter code generator - plugin #adobe xd flutter plugin #adobe xd flutter plugin tutorial #adobe xd plugins #adobe xd to flutter #adobe xd tutorial #codepen for flutter.