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Basic Android App using Google Maps and Current Location

Applies to:
What?
I am writing an app for a tablet running Android and wanted to include a Google Map. The following exercise focuses solely on creating an app which opens Google Maps at your current location.

How?
I couldn't find any instructions using the tools I had (Android Studio) which is why I've written this article.
  1. Start "Android Studio"

  2. Go to File and create a New Project...


  3. I'm developing on a Tablet so I select Phone and Tablet then a relatively old version of the Android OS:


  4. Add an activity to Mobile: select Google Maps Activity:


  5. Change the Title to what you want (don't change the activity or layout) and click on Finish:


  6. Get yourself a developers' Google Android Maps API Key (not necessarily the same as Google API Key) and enter it as instructed:


  7. Change the Java file to open on your current location, find the MapsActivity.java file and open it:


  8. Change the function setUpMap() to the following code
    copyraw 
    private void setUpMap() {
        mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker").snippet("Snippet"));

        // Enable MyLocation Layer of Google Map
        mMap.setMyLocationEnabled(true);

        // Get LocationManager object from System Service LOCATION_SERVICE
        LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

        // Create a criteria object to retrieve provider
        Criteria criteria = new Criteria();

        // Get the name of the best provider
        String provider = locationManager.getBestProvider(criteria, true);

        // Get Current Location
        Location myLocation = locationManager.getLastKnownLocation(provider);

        // set map type
        mMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);

        // Get latitude of the current location
        double latitude = myLocation.getLatitude();

        // Get longitude of the current location
        double longitude = myLocation.getLongitude();

        // Create a LatLng object for the current location
        LatLng latLng = new LatLng(latitude, longitude);

        // Show the current location in Google Map
        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));

        // Zoom in the Google Map
        mMap.animateCamera(CameraUpdateFactory.zoomTo(14));
        mMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("You are here!").snippet("Consider yourself located"));
    }
    1.  private void setUpMap() { 
    2.          mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker").snippet("Snippet")); 
    3.   
    4.          // Enable MyLocation Layer of Google Map 
    5.          mMap.setMyLocationEnabled(true); 
    6.   
    7.          // Get LocationManager object from System Service LOCATION_SERVICE 
    8.          LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 
    9.   
    10.          // Create a criteria object to retrieve provider 
    11.          Criteria criteria = new Criteria(); 
    12.   
    13.          // Get the name of the best provider 
    14.          String provider = locationManager.getBestProvider(criteria, true); 
    15.   
    16.          // Get Current Location 
    17.          Location myLocation = locationManager.getLastKnownLocation(provider); 
    18.   
    19.          // set map type 
    20.          mMap.setMapType(GoogleMap.MAP_TYPE_NORMAL); 
    21.   
    22.          // Get latitude of the current location 
    23.          double latitude = myLocation.getLatitude(); 
    24.   
    25.          // Get longitude of the current location 
    26.          double longitude = myLocation.getLongitude(); 
    27.   
    28.          // Create a LatLng object for the current location 
    29.          LatLng latLng = new LatLng(latitude, longitude); 
    30.   
    31.          // Show the current location in Google Map 
    32.          mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 
    33.   
    34.          // Zoom in the Google Map 
    35.          mMap.animateCamera(CameraUpdateFactory.zoomTo(14)); 
    36.          mMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("You are here!").snippet("Consider yourself located")); 
    37.      } 
    1. If you are prompted to import the classes then agree by clicking OK:


    2. If you are not prompted,
      1. you should see some of your code go red like in the following screenshot:


      2. Focus the cursor on the word and hold down the key and press Enter, then import each class:


  9. Your code will now include the imported classes near the beginning, so TEST it!



Addtional:
Problems animating the camera to your current location? I had to add the following:
copyraw 
LatLng myCoordinates = new LatLng(latitude, longitude);
CameraUpdate yourLocation = CameraUpdateFactory.newLatLngZoom(myCoordinates, 12);
mMap.animateCamera(yourLocation);
  1.  LatLng myCoordinates = new LatLng(latitude, longitude); 
  2.  CameraUpdate yourLocation = CameraUpdateFactory.newLatLngZoom(myCoordinates, 12); 
  3.  mMap.animateCamera(yourLocation); 

Additional Additional:
A little more control on the animation?
copyraw 
CameraPosition cameraPosition = new CameraPosition.Builder()
    .target(myCoordinates)      // Sets the center of the map to LatLng (refer to previous snippet)
    .zoom(17)                   // Sets the zoom
    .bearing(90)                // Sets the orientation of the camera to east
    .tilt(30)                   // Sets the tilt of the camera to 30 degrees
    .build();                   // Creates a CameraPosition from the builder
map.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
  1.  CameraPosition cameraPosition = new CameraPosition.Builder() 
  2.      .target(myCoordinates)      // Sets the center of the map to LatLng (refer to previous snippet) 
  3.      .zoom(17)                   // Sets the zoom 
  4.      .bearing(90)                // Sets the orientation of the camera to east 
  5.      .tilt(30)                   // Sets the tilt of the camera to 30 degrees 
  6.      .build();                   // Creates a CameraPosition from the builder 
  7.  map.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition)); 

Just in case: AndroidManifest.xml
The example above should have populated this correctly but if you are still getting problems, I have the following fields that I also use related to Google Maps v2:
copyraw 
<meta-data
        android:name="com.google.android.gms.version"
        android:value="@integer/google_play_services_version" />
<meta-data
        android:name="com.google.android.maps.v2.API_KEY"
        android:value="@string/google_maps_key" />
<permission
        android:name="package.name.permission.MAPS_RECEIVE"
        android:protectionLevel="signature" />
<uses-feature
        android:glEsVersion="0x00020000"
        android:required="true" />
<uses-library 
        android:name="com.google.android.maps" />
<uses-permission 
        android:name="package.name.permission.MAPS_RECEIVE" />
<uses-permission 
        android:name="android.permission.INTERNET" />
<uses-permission 
        android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<uses-permission 
        android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission 
        android:name="android.permission.ACCESS_FINE_LOCATION" />
  1.  <meta-data 
  2.          android:name="com.google.android.gms.version" 
  3.          android:value="@integer/google_play_services_version" /> 
  4.  <meta-data 
  5.          android:name="com.google.android.maps.v2.API_KEY" 
  6.          android:value="@string/google_maps_key" /> 
  7.  <permission 
  8.          android:name="package.name.permission.MAPS_RECEIVE" 
  9.          android:protectionLevel="signature" /> 
  10.  <uses-feature 
  11.          android:glEsVersion="0x00020000" 
  12.          android:required="true" /> 
  13.  <uses-library 
  14.          android:name="com.google.android.maps" /> 
  15.  <uses-permission 
  16.          android:name="package.name.permission.MAPS_RECEIVE" /> 
  17.  <uses-permission 
  18.          android:name="android.permission.INTERNET" /> 
  19.  <uses-permission 
  20.          android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" /> 
  21.  <uses-permission 
  22.          android:name="android.permission.ACCESS_COARSE_LOCATION" /> 
  23.  <uses-permission 
  24.          android:name="android.permission.ACCESS_FINE_LOCATION" /> 

Last Additional
Ensure that when Google asks for your Android API key, you enter the production key (which may be the same as your testing key); the one from your app and not from your computer (as other people don't use your computer to access the service). If your fellow testers only see a grey map, just double-check the key is the right one given to Google Maps.

Follow On Article/Sequel
Next: Article on separating the map into a sub-activity rather than it being the main activity - Android OS: Add GoogleMap as fragment.

Category: AndroidOS :: Article: 585