Java tutorial
//package com.java2s; import android.app.Activity; import android.os.Build; public class Main { public static void setHomeButtonEnabled(boolean homeButtonEnabled, Activity activity) { /* Beginning with Android 4.0 (API level 14), the icon must explicitly be enabled as an action item by calling setHomeButtonEnabled(true). In previous versions, the icon was enabled as an action item by default. */ if (Build.VERSION.SDK_INT >= 14) { activity.getActionBar().setHomeButtonEnabled(true); } } }