How to Hide/Remove ActionBar from an Activity

1. In the AndroidManifest.xml, add the below line between the activity tags.

<activity android:name="MyActivity"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
....>

2. Compile and run!

Resources:
http://stackoverflow.com/questions/8456835/how-to-disable-action-bar-permanently