Exercise 3 Creating a Google Map App using Android Studio - srihawi/AndroidExercises GitHub Wiki

Exercise 3 – Creating a Google Map Android App

Step 1 – Create a new Project in Android Studio and select Empty Activity

Step 2 − Add the following code to activity_main.xml

  <?xml version="1.0" encoding="utf-8"?>
  <fragment xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/myMap"
    android:name="com.google.android.gms.maps.SupportMapFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" />

Step 3 – Add the following dependency in the build.gradle (Module: app)

  implementation 'com.google.android.gms:play-services-maps:17.0.0'
  implementation 'com.google.android.gms:play-services-location:17.0.0'

Step 4 − Add the following code to src/MainActivity.java

    import android.Manifest;
    import android.content.pm.PackageManager;
    import android.location.Location;
    import android.os.Bundle;
    import android.widget.Toast;
    import com.google.android.gms.maps.CameraUpdateFactory;
    import com.google.android.gms.maps.SupportMapFragment;
    import com.google.android.gms.location.FusedLocationProviderClient;
    import com.google.android.gms.location.LocationServices;
    import com.google.android.gms.maps.GoogleMap;
    import com.google.android.gms.maps.OnMapReadyCallback;
    import com.google.android.gms.maps.model.LatLng;
    import com.google.android.gms.maps.model.MarkerOptions;
    import com.google.android.gms.tasks.OnSuccessListener;
    import com.google.android.gms.tasks.Task;
    import androidx.annotation.NonNull;
    import androidx.core.app.ActivityCompat;
    import androidx.fragment.app.FragmentActivity;
    public class MainActivity extends FragmentActivity implements OnMapReadyCallback {
    Location currentLocation;
    FusedLocationProviderClient fusedLocationProviderClient;
    private static final int REQUEST_CODE = 101;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this);
        fetchLocation();
    }
    private void fetchLocation() {
        if (ActivityCompat.checkSelfPermission(
                this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(
                this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_CODE);
            return;
        }
        Task<Location> task = fusedLocationProviderClient.getLastLocation();
        task.addOnSuccessListener(new OnSuccessListener<Location>() {
            @Override
            public void onSuccess(Location location) {
                if (location != null) {
                    currentLocation = location;
                    Toast.makeText(getApplicationContext(), currentLocation.getLatitude() + "" + currentLocation.getLongitude(), Toast.LENGTH_SHORT).show();
                    SupportMapFragment supportMapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.myMap);
                    assert supportMapFragment != null;
                    supportMapFragment.getMapAsync(MainActivity.this);
                }
            }
        });
    }
    @Override
    public void onMapReady(GoogleMap googleMap) {
        LatLng latLng = new LatLng(currentLocation.getLatitude(), currentLocation.getLongitude());
        MarkerOptions markerOptions = new MarkerOptions().position(latLng).title("I am here!");
        googleMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
        googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 5));
        googleMap.addMarker(markerOptions);
    }
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case REQUEST_CODE:
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    fetchLocation();
                }
                break;
        }
     }
     }

Step 5 – Open strings.xml and add the following code −

    <resources>
    <string name="app_name">MapsActivity</string>
    <string name="map_key" translatable="false">AIzaSyBiDrGj_6ILAZRrdPxvM2IgnhdxQIGjRUE</string>
    </resources>

Step 6 – To get the google API key (map_key), kindly follow the steps below

Visit the Google Cloud Platform Console (https://console.cloud.google.com/google/maps-apis/new?project=facebookagent-9f83d&folder=&organizationId=)

Click the project drop-down and select or create the project for which you want to add an API key. Click the menu button and select APIs & Services --> Credentials. On the Credentials page, click Create credentials --> API key. The API key created dialog displays your newly created API key. Click Close. The new API key is listed on the Credentials page under API keys. (Remember to restrict the API key before using it in production.)

Step 7 − Add the following code to androidManifest.xml

   <?xml version="1.0" encoding="utf-8"?>
   <manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.mapsactivity">
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.MapsActivity">
        <meta-data android:name="com.google.android.geo.API_KEY" android:value="@string/map_key"/>
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
    </manifest>

Next try to run your app assuming that you connected your mobile device to your computer. Select your device from Android studio and then click Run.