Tech Blog

I was trying to get an Android app that uses Google Maps API to display a MapView running on the emulator.  It took quite a bit of hair pulling to finally get it working.

First, I tried using a self-signed keystore instead of the the debug.keystore provided through the Android SDK.  I created my keystore using keytool -genkey from JDK.  Then I switch the app from using the default, debug.keystore, to my-new-self-signed.keystore.  Using keytool -list, I got the MD5 of the certificate that is needed to obtain a Google Map API key.  Then the API key was put into the MapView android:apikey attribute.  When I brought up the app in the emulator, I got a blank map grid screen.  The reason I wanted to use the self-signed keystore instead of the debug keystore is so I don’t have to obtain a new Map API key and change the code to reflect this upon releasing the app.

So, I decided to go with the debug.keystore and that worked fine.  Here is what I had to do.

1. $ keytool -list -alias androiddebugkey -keystore <path_to_debug_keystore>.keystore -storepass android -keypass android

2. Copy that MD5 and goto http://code.google.com/android/maps-api-signup.html
3. Signup for an API key
4. In my xml file that has the views for the activity, add

   <com.google.android.maps.MapView
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:enabled="true"
    android:clickable="true"
    android:apiKey="example_Maps_ApiKey_String"
    />

5. In the Manifest.xml file, add the permissions needed
   <uses-permission android:name=”android.permission.INTERNET”></uses-permission>
   <uses-permission android:name=”android.permission.ACCESS_FINE_LOCATION”></uses-permission>
6. In the Manifest.xml file, add the maps library
   <uses-library android:name=”com.google.android.maps” />
   within the application tag
7. The entire Manifest.xml looks like this
   <?xml version=”1.0″ encoding=”utf-8″?>
   <manifest xmlns:android=”http://schemas.android.com/apk/res/android”
   package=”com.informationideas.mapapp”
   android:versionCode=”1″
   android:versionName=”1.0.0″>
   <uses-permission android:name=”android.permission.INTERNET”></uses-permission>
   <uses-permission android:name=”android.permission.ACCESS_FINE_LOCATION”></uses-permission>
   <application android:icon=”@drawable/icon” android:label=”@string/app_name”>
   <uses-library android:name=”com.google.android.maps” />
   <activity android:name=”.ShowDesktop”
   android:label=”@string/app_name”>
   <intent-filter>
   <action android:name=”android.intent.action.MAIN” />
   <category android:name=”android.intent.category.LAUNCHER” />
   </intent-filter>
   </activity>
   </application>
   </manifest>
8. The default activity file should look like this

   package com.informationideas.mapapp;
   import android.os.Bundle;
   import com.google.android.maps.MapActivity;

   public class ShowDesktop extends MapActivity {

   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.main);

   }

   @Override
   protected boolean isRouteDisplayed() {
   // TODO Auto-generated method stub
   return false;
   }
   }

Now off to building cool things with the map!