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1. Challenges in Android Wear
Application Development
ICWE 2015
Jukka Ahola
VTT Technical Research Centre of Finland

2. 208/07/2015
The Story
 Social messaging application for Android Wear watch.
 Utilizes speech-to-text feature, combined with time and place.
 Other users receive messages near them.

3. 308/07/2015
The Application
 Watch Face application.
 BLE connected companion
application in Android phone.
 Web Service for message
storage and search functionality.

4. 408/07/2015
Development Issues
 Buttons do not work in Watch Face applications.
 Companion application in mobile phone is required for web service calls.
 Language preference cannot be selected in Android Wear application.

5. 508/07/2015
Workaround: Always-on Wear Application
styles.xml:
<style name="AppTheme" parent="@android:style/Theme.DeviceDefault">
<item name="android:windowSwipeToDismiss">false</item>
</style>
round_activity_main.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" tools:context=".MainActivity" tools:deviceIds="wear_round"
android:keepScreenOn="true">
MainActivity.java:
private DismissOverlayView mDismissOverlay;
private GestureDetector mDetector;
@Override
protected void onCreate(Bundle savedInstanceState) {
…
mDismissOverlay = (DismissOverlayView) findViewById(R.id.dismiss_overlay);
mDismissOverlay.setIntroText("QUIT APPLICATION");
mDismissOverlay.showIntroIfNecessary();
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
mDetector = new GestureDetector(this, new GestureDetector.SimpleOnGestureListener() {
public void onLongPress(MotionEvent ev) {
mDismissOverlay.show();
}
});
}
@Override
public boolean onTouchEvent(MotionEvent event) {
return mDetector.onTouchEvent(event) || super.onTouchEvent(event);
}
• Buttons work.
• Needs to be started.
• Consumes battery.

6. 608/07/2015
Android Wear and Wi-Fi Support?
 Limited to Android Wear watches supporting Wi-Fi.
 Do not work on Wi-Fi-networks requiring activation
(such as free airport wi-fi providers).
 If Wi-Fi is not available, you still have to delegate the web service
calls to the companion application through BLE communication.
Solution: seamless HttpURLConnection-class for Wear that utilizes
either direct Wi-Fi connectivity or network bridging through BLE-
connectivity.

7. 708/07/2015
Language Support
 Still ignores the language preferences set by the Wear application.
 Difficulties mixing two languages in one sentence.
For example, spelling foreign names or street addresses.
Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
Locale currentLocale = new Locale("fi_FI"); // Locale.ENGLISH;
String currentLanguage = "SUOMI"; // "ENGLISH";
intent.putExtra(RecognizerIntent.EXTRA_PROMPT, currentLanguage);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE, currentLocale.getLanguage());
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_PREFERENCE, currentLocale.getLanguage());
startActivityForResult(intent, SPEECH_REQUEST_CODE);

8. 808/07/2015
THANK YOU
Jukka Ahola
VTT Technical Research Centre of Finland LTD
jukka.ahola@vtt.fi
+358 40 076 4010
http://www.vtt.fi
LinkedIn: https://www.linkedin.com/in/jukkaahola

9. 908/07/2015
VTT creates business from
technology