Xamarin.Forms - Get Distance Between Two Coordinates Using GeoLocation Using Xamarin.Essentials

Introduction

 

 

 

Xamarin.Forms code runs on multiple platforms - each of which has its own filesystem. This means that reading and writing files are most easily done using the native file APIs on each platform. Alternatively, embedded resources are a simpler solution to distribute data files with an app.

 

Xamarin.Essentials

 

 

Xamarin.Essentials plugin provides 20+ cross-platform APIs for mobile application development. Xamarin.Essentials API works with all Xamarin.Forms, Xamarin.Android, Xamarin.iOS, or UWP application that can be accessed from shared code. We are developing Xamarin with Android, iOS and UWP apps but now Xamarin.Essentials overcomes the problem, and developers can access every native platform API using C#. This plugin provides many APIs so initially, there is no need for more plugins for Xamarin. Xamarin.Essentials plugin impacts your app's minimum size.

 

Platform Support

 

Xamarin.Essentials support platforms and operating systems,

 

Platform	Version
Android	4.4 (API 19) or earlier
iOS	10.0 or higher
UWP	10.0.16299.0 or earlier

 

Prerequisites

• Visual Studio 2017(Windows or Mac)

Setting up a Xamarin.Forms Project

 

Start by creating a new Xamarin.Forms project. You’ll learn more by going through the steps yourself.

 

Choose the Xamarin.Forms App Project type under Cross-platform/App in the New Project dialog.

 

 

 

Name your app, select “Use Portable Class Library” for shared code, and target both Android and iOS.

 

 

 

You probably want your project and solution to use the same name as your app. Put it in your preferred folder for projects and click Create.

 

 

 

You now have a basic Xamarin.Forms app. Click the play button to try it out.

 

 

 

Setting up the User Interface

 

Go to MainPage.Xaml and write the following code.

 

MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:XamarinEssentials"
             x:Class="XamarinEssentials.MainPage">

    <StackLayout>
        <StackLayout HorizontalOptions="Center" VerticalOptions="Start">
         <Image Margin="0,50,0,0" x:Name="imgBanner" Source="banner.png" ></Image>
         <Image Margin="0,0,0,10" x:Name="imgXamarinEssential" Source="xamarinessential.png" ></Image>
         <Label Margin="0,0,0,10" Text="GeoLocation" FontAttributes="Bold" FontSize="Large" TextColor="#CA6F1E" HorizontalTextAlignment="Center" ></Label>
         <Entry x:Name="txtSource" Placeholder="Source"></Entry>
         <Entry x:Name="txtDestination" Placeholder="Destination"></Entry>
         <Button x:Name="btnLocation" Text="Get Distance" Clicked="btnLocation_Clicked"/>
         <Label HorizontalTextAlignment="Center" x:Name="lblDistance"></Label>

        </StackLayout>
    </StackLayout>

</ContentPage>

Click the play button to try it out.

 

 

 

Add Xamarin Essentials

 

In this step, add Xamarin.Essentials to your project. You can install Xamarin.Essentials via NuGet, or you can browse the source code on GitHub.

 

Go to Solution Explorer and select your solution. Right-click and select "Manage NuGet Packages for Solution". Search "Xamarin.Essentials" and add Package. Remember to install it for each project (PCL, Android, iO, and UWP).

 

 

 

Xamarin.Essentials requires platform-specific setup - Android

The following steps are necessary for Android.

1. Xamarin.Essentials support a minimum Android version of 4.4
2. Target Android version for compiling must be 8.1, API level 27.

In the Android project's MainActivity that is launched Xamarin.Essentials must be initialized in the OnCreate method.

 

MainActivity.cs

Xamarin.Essentials.Platform.Init(this, bundle);

Xamarin.Essentials must receive any OnRequestPermissionsResult. write the following code for runtime permission.

 

MainActivity.cs

public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)
{
    Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);

    base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
}

iOS

 

No additional setup required.

 

UWP

 

No additional setup required.

 

Permissions - Android

 

AndroidManifest.xml

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-feature android:name="android.hardware.location" android:required="false" />
<uses-feature android:name="android.hardware.location.gps" android:required="false" />
<uses-feature android:name="android.hardware.location.network" android:required="false" />

Permissions - iOS

• Privacy - Location When In Use Usage Description

In this step, write the following code for Get Distance between two Coordinates using GeoLocation using Xamarin.Essentials.

 

MainPage.xaml.cs

using Xamarin.Forms;
using Xamarin.Essentials;
namespace XamarinEssentials
{
    public partial class MainPage : ContentPage
    {
        public MainPage()
        {
            InitializeComponent();
        }
        protected override void OnAppearing()
        {
            base.OnAppearing();
        }


        async void btnLocation_Clicked(object sender, System.EventArgs e)
        {
            try
            {
                var source = txtSource.Text;
                var sourceLocation = await Geocoding.GetLocationsAsync(source);
                var destination = txtDestination.Text;
                var destinationLocation = await Geocoding.GetLocationsAsync(destination);
                if(sourceLocation!=null)
                {
                    var sourceLocations = sourceLocation?.FirstOrDefault();
                    var destinationLocations = destinationLocation?.FirstOrDefault();
                    Location sourceCoordinates = new Location(sourceLocations.Latitude,sourceLocations.Longitude);
                    Location destinationCoordinates = new Location(destinationLocations.Latitude,destinationLocations.Longitude);
                    double distance = Location.CalculateDistance(sourceCoordinates, destinationCoordinates, DistanceUnits.Miles);
                    lblDistance.Text = distance.ToString();
                }



            }
            catch (FeatureNotSupportedException fnsEx)
            {
                 await DisplayAlert("Faild", fnsEx.Message, "OK");
            }
            catch (PermissionException pEx)
            {
                await DisplayAlert("Faild", pEx.Message, "OK");
            }
            catch (Exception ex)
            {
                await DisplayAlert("Faild", ex.Message, "OK");
            }

        }
    }
}

Click the play button to try it out.

 

 

 

I hope you have understood how to get the distance between two coordinates using Xamarin Essentials in Xamarin.Forms.

 

Thanks for reading. Please share your comments and feedback.