I recently bought a T-Mobile G1 and I have been looking at learning how to write applications for it. I thought I would put up a quick tutorial on how to add text-to-speech capabilities to the translation application. The translation application was written by Cédric Beust.

Preliminaries:

Download and install the Android Software Development kit from here:

http://code.google.com/android/intro/installing.html

Information about using the Text-to-speech API can be found here:

http://eyes-free.googlecode.com/svn/trunk/documentation/tutorial/tutorial.html

Information about the Translation application can be found here:

http://beust.com/weblog/archives/000500.html

You can find information and source-code for applications that people from Google have written for Android here: http://code.google.com/p/apps-for-android/

1. Download the source code for the the Translate application.

You can use any svn client that you want to download the source code for the Translator application. I used tortoisecvs. Create a directory somewhere, and download the source code from http://apps-for-android.googlecode.com/svn/trunk/Translate

2. Create a new project in Eclipse

Select File->new->Android Project. Then select the option to "Create a New Project from existing source". Under location, click browse and select the directory where you downloaded the Translator files to. Give the project a name that is meaningful to you. I chose "TranslateActivity2". The other fields are automatically filled in for you.

3. Download the TTS library and add it as an external library

Download the tts library stub from here:

http://eyes-free.googlecode.com/svn/trunk/commonlibs/TTS_library_stub.jar

Go to Project > Properties > Java Build Path > Libraries and click on "Add External JARs..." Then add in the TTS_library_stub.jar file.

4. Edit the source code to use the TTS library

In the TranslateActivity.java file make the following changes:

In the imports section, add

import com.google.tts.TTS;

After the line "public class TranslateActivity extends Activity implements OnClickListener {" add a line that says:

private TTS myTts;

In the "onCreate(Bundle icicle)" method add:

myTts = new TTS(this, ttsInitListener, true);

After the oncreate method add:

private TTS.InitListener ttsInitListener = new TTS.InitListener() { public void onInit(int version) { } };

In the "doTranslate" method, after "setOutputText(result);" add:

myTts.speak(result, 0, null);

In the "setNewLanguage" method, add:

if(from) { if(language.getShortName().contains("zh")) myTts.setLanguage("zh"); else myTts.setLanguage(language.getShortName()); }

Conclusion

In this quick tutorial, I have shown you how to add speech to a real application using the text to speech library. I hope you have found it useful. Also, I hope they will include text to speech in a future version of the Translate application.