Android-Rodies-Task: Drawing Polyline and Markers along the tapped positions in Google Map Android API V2 using ArrayList

In this article, we will create an Android application which draws polyline and markers along the tapped positions in Google Map Android API V2. Long click the Google Map to clear all the existing polylines and markers in the Google Map.

This application is developed in Eclipse 4.2.1 with ADT plugin ( 21.1.0 ) and Android SDK ( 21.1.0 ) and is tested in a real Android Phone with Android ( 2.3.6 ).

Download and configure Google Play Services Library in Eclipse

Google Map 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

Note : Please ensure that, the latest version of Google Play Service Library is installed

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

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 window, Click “Android Tools -> Add Support Library “

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"

        class="com.google.android.gms.maps.SupportMapFragment"/>

</RelativeLayout>

Update the file src/in//locationmarkerlatlng/MainActivity.java

import java.util.ArrayList;

import android.graphics.Color;

import android.os.Bundle;

import android.support.v4.app.FragmentActivity;

import android.view.Menu;

import com.google.android.gms.maps.GoogleMap;

import com.google.android.gms.maps.GoogleMap.OnMapClickListener;

import com.google.android.gms.maps.GoogleMap.OnMapLongClickListener;

import com.google.android.gms.maps.SupportMapFragment;

import com.google.android.gms.maps.model.LatLng;

import com.google.android.gms.maps.model.MarkerOptions;

import com.google.android.gms.maps.model.PolylineOptions;

public class MainActivity extends FragmentActivity {

    GoogleMap googleMap;

    ArrayList<LatLng> points;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        points = new ArrayList<LatLng>();

        // 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);

        // Setting OnClick event listener for the Google Map

        googleMap.setOnMapClickListener(new OnMapClickListener() {

            @Override

            public void onMapClick(LatLng point) {

                // Instantiating the class MarkerOptions to plot marker on the map

                MarkerOptions markerOptions = new MarkerOptions();

                // Setting latitude and longitude of the marker position

                markerOptions.position(point);

                // Setting titile of the infowindow of the marker

                markerOptions.title("Position");

                // Setting the content of the infowindow of the marker

                markerOptions.snippet("Latitude:"+point.latitude+","+"Longitude:"+point.longitude);

                // Instantiating the class PolylineOptions to plot polyline in the map

                PolylineOptions polylineOptions = new PolylineOptions();

                // Setting the color of the polyline

                polylineOptions.color(Color.RED);

                // Setting the width of the polyline

                polylineOptions.width(3);

                // Adding the taped point to the ArrayList

                points.add(point);

                // Setting points of polyline

                polylineOptions.addAll(points);

                // Adding the polyline to the map

                googleMap.addPolyline(polylineOptions);

                // Adding the marker to the map

                googleMap.addMarker(markerOptions);

            }

        });

        googleMap.setOnMapLongClickListener(new OnMapLongClickListener() {

            @Override

            public void onMapLongClick(LatLng point) {

                // Clearing the markers and polylines in the google map

                googleMap.clear();

                // Empty the array list

                points.clear();

            }

        });

    }

    @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;

    }

}

Update the file AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="in..locationpolyline"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="8"

        android:targetSdkVersion="17" />

    <permission

        android:name="in..locationpolyline.permission.MAPS_RECEIVE"

        android:protectionLevel="signature"/>

    <uses-permission android:name="in..locationpolyline.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..locationpolyline.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_API_KEY"/>

    </application>

</manifest>