Xamarin.Forms - Developing A Geocoding Application Using Xamarin.Essentials

Introduction
 
Xamarin.Forms - GeoCoding Using Xamarin Essentials
 
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.Forms - GeoCoding Using 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 applications 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 supports 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.
 
Xamarin.Forms - GeoCoding Using Xamarin Essentials
 
Name your app, select “Use Portable Class Library” for shared code, and target both Android and iOS.
 
Xamarin.Forms - GeoCoding Using Xamarin Essentials
 
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.
 
Xamarin.Forms - GeoCoding Using Xamarin Essentials
 
You now have a basic Xamarin.Forms app. Click the play button to try it out.
 
Xamarin.Forms - GeoCoding Using Xamarin Essentials
 
Setting up the User Interface
 
Go to MainPage.Xaml and write the following code.
 
MainPage.xaml
  1. <?xml version="1.0" encoding="utf-8" ?>  
  2. <ContentPage xmlns="http://xamarin.com/schemas/2014/forms"  
  3.              xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"  
  4.              xmlns:local="clr-namespace:XamarinEssentials"  
  5.              x:Class="XamarinEssentials.MainPage">  
  6.   
  7.     <StackLayout>  
  8.         <StackLayout HorizontalOptions="Center" VerticalOptions="Start">  
  9.          <Image Margin="0,50,0,0" x:Name="imgBanner" Source="banner.png" ></Image>  
  10.          <Image Margin="0,0,0,10" x:Name="imgXamarinEssential" Source="xamarinessential.png" ></Image>  
  11.          <Label Margin="0,0,0,10" Text="Geocoding" FontAttributes="Bold" FontSize="Large" TextColor="#CA6F1E" HorizontalTextAlignment="Center" ></Label>  
  12.          <Entry x:Name="txtAddress" Placeholder="Search Location..."></Entry>  
  13.          <Button x:Name="btnLocation" Text="Get Location" Clicked="btnLocation_Clicked"/>  
  14.          <Label HorizontalTextAlignment="Center" x:Name="lblLatitude"></Label>  
  15.          <Label HorizontalTextAlignment="Center" x:Name="lblLongitude"></Label>  
  16.   
  17.         </StackLayout>  
  18.     </StackLayout>  
  19.   
  20. </ContentPage>  
Click the play button to try it out.
 
Xamarin.Forms - GeoCoding Using Xamarin Essentials
 
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.Forms - GeoCoding Using Xamarin Essentials
 
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 -- it 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
  1. Xamarin.Essentials.Platform.Init(this, bundle);  
Xamarin.Essentials must receive any OnRequestPermissionsResult. Write the following code for runtime permission.
 
MainActivity.cs
  1. public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)  
  2. {  
  3.     Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);  
  4.   
  5.     base.OnRequestPermissionsResult(requestCode, permissions, grantResults);  
  6. }  
iOS
 
No additional setup required.
 
UWP
 
No additional setup required.
 
Permissions - Android
 
AndroidManifest.xml,
  1. <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />  
  2. <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />  
  3. <uses-feature android:name="android.hardware.location" android:required="false" />  
  4. <uses-feature android:name="android.hardware.location.gps" android:required="false" />  
  5. <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 getting Latitude and Longitude by address using Xamarin.Essentials.
 
MainPage.xaml.cs
  1. using Xamarin.Forms;  
  2. using Xamarin.Essentials;  
  3. namespace XamarinEssentials  
  4. {  
  5.     public partial class MainPage : ContentPage  
  6.     {  
  7.         public MainPage()  
  8.         {  
  9.             InitializeComponent();  
  10.         }  
  11.         protected override void OnAppearing()  
  12.         {  
  13.             base.OnAppearing();  
  14.         }  
  15.   
  16.   
  17.         async void btnLocation_Clicked(object sender, System.EventArgs e)  
  18.         {  
  19.             try  
  20.             {  
  21.                 var address = txtAddress.Text;  
  22.                 var locations = await Geocoding.GetLocationsAsync(address);  
  23.   
  24.                 var location = locations?.FirstOrDefault();  
  25.   
  26.                 if(location!=null)  
  27.                 {  
  28.                     lblLatitude.Text ="Latitude: " +location.Latitude.ToString();  
  29.                     lblLongitude.Text ="Longitude: "+ location.Longitude.ToString();  
  30.                 }  
  31.             }  
  32.             catch (FeatureNotSupportedException fnsEx)  
  33.             {  
  34.                  await DisplayAlert("Faild", fnsEx.Message, "OK");  
  35.             }  
  36.             catch (PermissionException pEx)  
  37.             {  
  38.                 await DisplayAlert("Faild", pEx.Message, "OK");  
  39.             }  
  40.             catch (Exception ex)  
  41.             {  
  42.                 await DisplayAlert("Faild", ex.Message, "OK");  
  43.             }  
  44.   
  45.         }  
  46.     }  
  47. }  
Click the play button to try it out.
 
Xamarin.Forms - GeoCoding Using Xamarin Essentials
 
I hope you have understood how to get Location by address Using Xamarin Essentials in Xamarin.Forms.
 
Thanks for reading. Please share comments and feedback.