In this article, we will develop an Android application which demonstrates how to update InfoWindow contents with coordinates when dragging marker in Google Maps Android API V2.
In order to drag a marker in the Google Maps, we need to long press the marker and then drag the marker to new position.
This application is developed in Eclipse (4.2.1) with ADT plugin (21.1.0) and Android SDK (21.1.0) and tested in a real Android device (Android 2.3.6 - GingerBread).
1. Create a new Android application project namely “LocationDraggableMarkerMapV2″
Figure 1 : Create new Android application project
2. Configure the project
Figure 2 : Configure the application project
3. Design application launcher icon
Figure 3 : Design application launcher icon
4. Create a blank activity
Figure 4 : Create a blank activity
5. Enter MainActivity details
Figure 5 : Enter MainActivity details
6. Download and configure Google Play Services Library in Eclipse
Google Maps for Android is now integrated with Google Play Services. So we need to set up Google Play Service Library for developing Google Map application in Android.
Please follow the given below link to setup Google Play Service library in Eclipse.
http://developer.android.com/google/play-services/setup.html
7. Add Google Play Services Library to this project
Figure 6 : Link Google Play Services Library
8. Get the API key for Google Maps Android API V2
We need to get an API key from Google to use Google Maps in Android application.
Please follow the given below link to get the API key for Google Maps Android API v2.
https://developers.google.com/maps/documentation/android/start
9. Add Android Support library to this project
By default, Android support library (android-support-v4.jar ) is added to this project by Eclipse IDE to the directory libs. If it is not added, we can do it manually by doing the following steps :
- Open Project Explorer by Clicking “Window -> Show View -> Project Explorer”
- Right click this project
- Then from popup menu, Click “Android Tools -> Add Support Library “
10. Update the layout file res/layout/activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<fragment
android:id="@+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
11. Update the class “MainActivity” in the file src/in/wptrafficanalyzer/locationdraggablemarkermapv2/MainActivity.java
package in.wptrafficanalyzer.locationdraggablemarkermapv2;
import android.app.Dialog;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.view.Menu;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnMapClickListener;
import com.google.android.gms.maps.GoogleMap.OnMarkerDragListener;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
public class MainActivity extends FragmentActivity {
GoogleMap googleMap;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Getting Google Play availability status
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getBaseContext());
if(status!=ConnectionResult.SUCCESS){ // Google Play Services are not available
int requestCode = 10;
Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this, requestCode);
dialog.show();
}else { // Google Play Services are available
// Getting reference to the SupportMapFragment of activity_main.xml
SupportMapFragment fm = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
// Getting GoogleMap object from the fragment
googleMap = fm.getMap();
// Enabling MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
googleMap.setOnMapClickListener(new OnMapClickListener() {
@Override
public void onMapClick(LatLng point) {
drawMarker(point);
}
});
googleMap.setOnMarkerDragListener(new OnMarkerDragListener() {
@Override
public void onMarkerDragStart(Marker marker) {
// TODO Auto-generated method stub
}
@Override
public void onMarkerDragEnd(Marker marker) {
// TODO Auto-generated method stub
}
@Override
public void onMarkerDrag(Marker marker) {
// Getting the current position of the marker
LatLng pos = marker.getPosition();
// Updating the infowindow contents with the new marker coordinates
marker.setSnippet(pos.latitude + "," + pos.longitude);
// Updating the infowindow for the user
marker.showInfoWindow();
}
});
}
}
private void drawMarker(LatLng point){
// Creating an instance of MarkerOptions
MarkerOptions markerOptions = new MarkerOptions();
// Setting latitude and longitude for the marker
markerOptions.position(point);
// Making this marker draggable
markerOptions.draggable(true);
// Title for this marker
markerOptions.title("Marker Coordinates");
// Coordinates for this marker as infowindow contents
markerOptions.snippet(Double.toString(point.latitude)+","+Double.toString(point.longitude));
// Adding marker on the Google Map
googleMap.addMarker(markerOptions);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
12. Update the file AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="in.wptrafficanalyzer.locationdraggablemarkermapv2"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<permission
android:name="in.wptrafficanalyzer.locationdraggablemarkermapv2.permission.MAPS_RECEIVE"
android:protectionLevel="signature"/>
<uses-permission android:name="in.wptrafficanalyzer.locationdraggablemarkermapv2.permission.MAPS_RECEIVE"/>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<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"/>
<uses-feature
android:glEsVersion="0x00020000"
android:required="true"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="in.wptrafficanalyzer.locationdraggablemarkermapv2.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<meta-data
android:name="com.google.android.maps.v2.API_KEY"
android:value="YOUR_ANDROID_API_KEY" />
</application>
</manifest>
Note : Replace “YOUR_ANDROID_API_KEY” at the line 44 with Google Maps Android API V2 api key obtained in Step 8.
13. Running the application
Figure 7 : Screenshot of the application in execution
14. Download source code of this Android application
I am George Mathew, working as software architect and Android app developer at wptrafficanalyzer.in
You can hire me on hourly basis or on project basis for Android applications development.
For hiring me, please mail your requirements to info@wptrafficanalyzer.in.
My other blogs
store4js.blogspot.com
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