hide actionbar from android code example

Example 1: android java remove action bar

ActionBar actionBar=getSupportActionBar();
    actionBar.hide();

Example 2: make activity no action bar

<application
    android:allowBackup = "true"
    android:icon = "@drawable/ic_launcher"
    android:label = "@string/app_name"
    android:theme = "@style/NoActionBar"   <!--This is the important line-->
    >
    <activity
    [...]