Since AndroidAnnotations 1.0

Since Android 2.0, activities can implement onBackPressed() to modify the default behavior when the user presses the back key.

There was an article on the Android blog that showed how to reproduce this for pre 2.0 Android versions.

We automatically support that since AndroidAnnotations 2.1 (with issue 46): if an @EActivity annotated class has an onBackPressed() method, the generated class adds the needed code for support on pre 2.0 Android versions.

For instance:

@EActivity
public class MyActivity extends Activity {
    
    public void onBackPressed() {
        // Do something
    }

}

Generates:

public final class MyActivity_ extends MyActivity
{

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (((SdkVersionHelper.getSdkInt()< 5)&&(keyCode == KeyEvent.KEYCODE_BACK))&&(event.getRepeatCount() == 0)) {
            onBackPressed();
        }
        return super.onKeyDown(keyCode, event);
    }

}