Blog post for this article can be found here : http://blog.doityourselfandroid.com/2011/08/06/oauth-2-0-flow-android/

In order to run the sample, make sure you do the necessary preperations in the Google API console, 
and provide your OAuth 2.0 details in https://github.com/ddewaele/AndroidOauth2GoogleApiJavaClient/blob/master/src/com/ecs/android/sample/oauth2/OAuth2ClientCredentials.java

I've updated the sample to inclue the libraries in Git. You should be able to checkout / build / run without worrying about dependencies.

For the sake of clarity, following dependencies are required in order to run the application :

M2_REPO/commons-codec/commons-codec/1.3/commons-codec-1.3.jar
M2_REPO/commons-logging/commons-logging/1.1.1/commons-logging-1.1.1.jar
M2_REPO/com/google/api/client/google-api-client/1.4.1-beta/google-api-client-1.4.1-beta.jar 
M2_REPO/com/google/api/client/google-api-client-googleapis/1.4.1-beta/google-api-client-googleapis-1.4.1-beta.jar 
M2_REPO/com/google/api/services/latitude/google-api-services-latitude-v1/1.1.0-beta/google-api-services-latitude-v1-1.1.0-beta.jar 
M2_REPO/com/google/code/gson/gson/1.6/gson-1.6.jar 
M2_REPO/com/google/guava/guava/r09/guava-r09.jar 
M2_REPO/org/apache/httpcomponents/httpclient/4.0.3/httpclient-4.0.3.jar 
M2_REPO/org/apache/httpcomponents/httpcore/4.0.1/httpcore-4.0.1.jar 
M2_REPO/org/codehaus/jackson/jackson-core-asl/1.6.7/jackson-core-asl-1.6.7.jar