Google Maps Integration In Xamarin Forms

In this article, we will discuss how to integrate Google Maps in Xamarin Forms Projects. The steps are, as follows:

In Visual Studio, create a Xamarin Portable Project. Go to New Project -> Cross-Platform -> Blank App (Xamarin.Form.Portable).

Add NuGet package Xamarin.Forms.Maps for each project. You can do this by right clicking on Solution Explorer and clicking Manage NuGet Package for Solution.

In iOS project, double click the AppDelegate.cs file and Add Xamarin.FormsMaps.Init(); in FinishedLauching Function.



In Android project, double click the MainActivity.cs file and Xamarin.FormsMaps.Init(); in Oncreate Function.



In Windows Runtime Project and Universal Windows Platform(UWP) project, double click the MainPage.xaml.cs and add Xamarin.FormsMaps.Init("INSERT_AUTHENTICATION_TOKEN_HERE");. The Token is discussed in further Points.

In Android project, we need to create an API key. To create the API key, go to C:\Users\Admin\AppData\Local\Xamarin\Mono and then copy debug.keystore file.

Now, go to C:\Program Files\Java\jre1.8.0_73\bin and paste the copied debug.keystore file.

Open Command Prompt – go C:\Program Files\Java\jre1.8.0_73\bin and run the command:

keytool -list -v -keystore debug.keystore -alias androiddebugkey -storepass android -keypass android

Your SHA1 Key is created. Store the SHA1 key which is further required for creating the API Key.

Now, create project, as shown in the below screen shot, by going to the link as https://console.developers.google.com/ and signing in with your Google account.



Next, it's showing New Project popup window; here, give your Project Name to create a new project.



Then, go for Google APIs and select Google Maps Android API.



Enable Google Android API.



After enabling Google API, go to Google API credentials page.



Then, select configure and select the value to Android in the dropdown.  Next, click What credentials do I need? button.



Windows is showing. Create as API Key to give your project a name and click Add Package name and fingerprint button. Then, give package name as google.maps.key. Now, copy and paste the SHA1 Key here.



Then, click Create API Key button. It returns APIs Page. It will be showing API key.



Then, in this API, a key is added to the AndroidManifest.XML file of a Xamarin Android application. Add the following code, and give package name as google.maps.key in manifest file.



Now, You'll also need to enable appropriate permissions by right-clicking on the Android project and selecting Properties -> Android Manifest, as shown in the below screen.



In Portable project, add page as “Mapspage.cs” and write the code, as given below.

using System;
using Xamarin.Forms;
using Xamarin.Forms.Maps;
using System.Diagnostics;
namespace XamarinMapSample {
    public class MapPage: ContentPage {
        Map map;
        public MapPage() {
            map = new Map {
                IsShowingUser = true,
                    HeightRequest = 100,
                    WidthRequest = 960,
                    VerticalOptions = LayoutOptions.FillAndExpand
            };
            // You can use MapSpan.FromCenterAndRadius
            map.MoveToRegion(MapSpan.FromCenterAndRadius(new Position(37, -122), Distance.FromMiles(0.3)));
            // or create a new MapSpan object directly
            //map.MoveToRegion(new MapSpan(new Position(0, 0), 360, 360));
            // add the slider
            var slider = new Slider(1, 18, 1);
            slider.ValueChanged += (sender, e) => {
                var zoomLevel = e.NewValue; // between 1 and 18
                var latlongdegrees = 360 / (Math.Pow(2, zoomLevel));
                Debug.WriteLine(zoomLevel + " -> " + latlongdegrees);
                if (map.VisibleRegion != null) map.MoveToRegion(new MapSpan(map.VisibleRegion.Center, latlongdegrees, latlongdegrees));
            };
            // create map style buttons
            var street = new Button {
                Text = "Street"
            };
            var hybrid = new Button {
                Text = "Hybrid"
            };
            var satellite = new Button {
                Text = "Satellite"
            };
            street.Clicked += HandleClicked;
            hybrid.Clicked += HandleClicked;
            satellite.Clicked += HandleClicked;
            var segments = new StackLayout {
                Spacing = 30,
                    HorizontalOptions = LayoutOptions.CenterAndExpand,
                    Orientation = StackOrientation.Horizontal,
                    Children = {
                        street,
                        hybrid,
                        satellite
                    }
            };
            // put the page together
            var stack = new StackLayout {
                Spacing = 0
            };
            stack.Children.Add(map);
            stack.Children.Add(slider);
            stack.Children.Add(segments);
            Content = stack;
            // for debugging output only
            map.PropertyChanged += (sender, e) => {
                Debug.WriteLine(e.PropertyName + " just changed!");
                if (e.PropertyName == "VisibleRegion" && map.VisibleRegion != null) CalculateBoundingCoordinates(map.VisibleRegion);
            };
        }
        void HandleClicked(object sender, EventArgs e) {
                var b = sender as Button;
                switch (b.Text) {
                    case "Street":
                        map.MapType = MapType.Street;
                        break;
                    case "Hybrid":
                        map.MapType = MapType.Hybrid;
                        break;
                    case "Satellite":
                        map.MapType = MapType.Satellite;
                        break;
                }
            }
            /// <summary>
            /// In response to this forum question http://forums.xamarin.com/discussion/22493/maps-visibleregion-bounds
            /// Useful if you need to send the bounds to a web service or otherwise calculate what
            /// pins might need to be drawn inside the currently visible viewport.
            /// </summary>
        static void CalculateBoundingCoordinates(MapSpan region) {
            // WARNING: I haven't tested the correctness of this exhaustively!
            var center = region.Center;
            var halfheightDegrees = region.LatitudeDegrees / 2;
            var halfwidthDegrees = region.LongitudeDegrees / 2;
            var left = center.Longitude - halfwidthDegrees;
            var right = center.Longitude + halfwidthDegrees;
            var top = center.Latitude + halfheightDegrees;
            var bottom = center.Latitude - halfheightDegrees;
            // Adjust for Internation Date Line (+/- 180 degrees longitude)
            if (left < -180) left = 180 + (180 + left);
            if (right > 180) right = (right - 180) - 180;
            // I don't wrap around north or south; I don't think the map control allows this anyway
            Debug.WriteLine("Bounding box:");
            Debug.WriteLine(" " + top);
            Debug.WriteLine(" " + left + " " + right);
            Debug.WriteLine(" " + bottom);
        }
    }
}

In App.cs file, change the code, as shown in the screenshot.



You can run the Android & iOS Project to check the output.