How to fix "Call requires API level 11" with Android Activity?

Question

I'm just starting to do Android development, more-or-less following the http://developer.android.com/training/basics/firstapp/starting-activity.html tutorial, and one thing keeps bugging me: I have two classes, both created using the "Android Activity" creation wizard:

public class PlacesActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_places);
        // I manually commented out the following line to get it to compile.
        // getActionBar().setDisplayHomeAsUpEnabled(true);
    }
    // ... other methods
}

and

public class ShowOnePlace extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_show_one_place);
        getActionBar().setDisplayHomeAsUpEnabled(true);
    }
    // ... other methods
}

Eclipse kept giving me the following errors:

Call requires API level 11 (current min is 8): android.app.Activity#getActionBar

Call requires API level 11 (current min is 8): android.app.ActionBar#setDisplayHomeAsUpEnabled

until I commented out one of the lines (as shown above). Now the application seems to compile and run on my Android device without errors. (Well, at least without that error).

So:

• Why is getActionBar().setDisplayHomeAsUpEnabled(true); give that error in one class, but that exact same line is not an error -- not even a warning -- in the other class?
• Is there a bug in the "Android Activity" creation wizard, and somehow that getActionBar().setDisplayHomeAsUpEnabled(true); statement is wrong in one activity, but perfectly fine in the other?
• Is maybe there a bug in Eclipse Lint, and that statement is actually OK in both activities (or perhaps wrong in both activities)?
• What do I have to do so that I can fix this without changing minSdkVersion="8" to minSdkVersion="11"? I was under the impression that the "android-support-v4.jar" file was a compatibility library that ran on version 8 devices to handle stuff that's handled natively in version 11 devices.
• What's really the Right Thing to Do when I see this error?

Answer 1

Use getSupportActionBar() instead of getActionBar(). That will provide ActionBar features on API levels below 11.