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Xamarin forms Geolocation wrong results

发布于 2020-12-03 12:01:06

I am developing a Xamarin forms application and trying to use Xamarin.Essentials Geolocation to determine my device location for Android. I followed the steps from https://docs.microsoft.com/en-us/xamarin/essentials/geolocation?tabs=android however the results are completely inaccurate as I am currently in central Europe but the result latitude and longitude is 37.4219983333333 and -122.084 which is location of Google's headquarters i guess.

Here is how my AndroidManifest.xml looks like

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.companyname.workingwithmaps">
  <uses-sdk android:minSdkVersion="21" />
  <application android:label="WorkingWithMaps.Android">
    <meta-data android:name="com.google.android.geo.API_KEY" android:value="MY_API_KEY" />
    <meta-data android:name="com.google.android.gms.version" android:value="@integer/google_play_services_version" />
    <!-- Necessary for apps that target Android 9.0 or higher -->
    <uses-library android:name="org.apache.http.legacy" android:required="false" />
  </application>
  <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
  <uses-permission android:name="android.permission.ACCESS_COARSE_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" />
</manifest>

My MainActivity.cs class:

 [Activity(Label = "Resti", Icon = "@mipmap/icon", Theme = "@style/MainTheme", MainLauncher = true, ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]
  public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
  {
    public override void OnRequestPermissionsResult(int requestCode, string[] permissions, Android.Content.PM.Permission[] grantResults)
    {
      Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);

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

    protected override void OnCreate(Bundle savedInstanceState)
    {
      TabLayoutResource = Resource.Layout.Tabbar;
      ToolbarResource = Resource.Layout.Toolbar;

      base.OnCreate(savedInstanceState);

      Xamarin.Essentials.Platform.Init(this, savedInstanceState);
      global::Xamarin.Forms.Forms.SetFlags("CollectionView_Experimental");
      Xamarin.Essentials.Platform.Init(this, savedInstanceState);
      global::Xamarin.Forms.Forms.Init(this, savedInstanceState);
      Xamarin.FormsMaps.Init(this, savedInstanceState);
      LoadApplication(new App());
    }
  }

And than I call it from ContentPage like this:

 protected async override void OnAppearing()
 {
      Xamarin.Essentials.Location location = null;

      var request = new GeolocationRequest(GeolocationAccuracy.Medium, TimeSpan.FromSeconds(10));
      cts = new CancellationTokenSource();
      location = await Geolocation.GetLocationAsync(request, cts.Token);
      base.OnAppearing();
 }

Any idea what I am doing wrong?

Questioner
Jenism
Viewed
0
Jenism 2020-12-03 21:48:02

I was testing this functionallity on emulator and as i have found out thanks to Jason, the emulator doesn't have actual GPS capabilities, it uses a mock location by default.