Here's your code with the interface implemented:
public class SpeechHelper implements OnInitListener {
private TextToSpeech speech;
private Context context = null;
public SpeechHelper(Context context)
{
this.context = context;
speech = new TextToSpeech(context, this);
}
@Override
public void onInit(int status) {
// TextToSpeech engine is initialized
}
}