Wednesday, June 08, 2011

Add Gesture Search to your Android apps

By Yang Li, Research Scientist

Gesture Search from Google Labs now has an API. You can use the API to easily integrate Gesture Search into your Android apps, so your users can gesture to write text and search for application-specific data. For example, a mobile ordering application for a restaurant might have a long list of menu items; with Gesture Search, users can draw letters to narrow their search.

Another way to use Gesture Search is to enable users to select options using gestures that correspond to specific app functions, like a touch screen version of keyboard shortcuts, rather than forcing hierarchical menu navigation.

In this post, I’ll demonstrate how we can embed Gesture Search (1.4.0 or later) into an Android app that enables a user to find information about a specific country. To use Gesture Search, we first need to create a content provider named CountryProvider, according to the format required by Android Search framework. This content provider consists of 238 country names.

Then, in GestureSearchAPIDemo, the main activity of the app, we invoke Gesture Search when a user selects a menu item. (Gesture Search can be invoked in other ways depending on specific applications.) To do this, we create an Intent with the action "" and the URI of the content provider. If the data is protected (for example, see AndroidManifest.xml), we also need to grant read permission for the content URI to Gesture Search. We then call startActivityForResult to invoke Gesture Search.
public boolean onCreateOptionsMenu(Menu menu) {
    menu.add(0, GESTURE_SEARCH_ID, 0, R.string.menu_gesture_search)
        .setShortcut('0', 'g').setIcon(android.R.drawable.ic_menu_search);
    return true;

  public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        try {
          Intent intent = new Intent();
          intent.putExtra(SHOW_MODE, SHOW_ALL);
          intent.putExtra(THEME, THEME_LIGHT);
          startActivityForResult(intent, GESTURE_SEARCH_ID);
        } catch (ActivityNotFoundException e) {
          Log.e("GestureSearchExample", "Gesture Search is not installed");
    return super.onOptionsItemSelected(item);
In the code snippet above, we also specify that we want to show all of the country names when Gesture Search is brought up by intent.putExtra(SHOW_MODE, SHOW_ALL). The parameter name and its possible values are defined as follows:
   * Optionally, specify what should be shown when launching Gesture Search.
   * If this is not specified, SHOW_HISTORY will be used as a default value.
  private static String SHOW_MODE = "show";
  /** Possible values for invoking mode */
  // Show the visited items
  private static final int SHOW_HISTORY = 0;
  // Show nothing (a blank screen)
  private static final int SHOW_NONE = 1;
  // Show all of date items
  private static final int SHOW_ALL = 2;

   * The theme of Gesture Search can be light or dark. 
   * By default, Gesture Search will use a dark theme.
  private static final String THEME = "theme";
  private static final int THEME_LIGHT = 0;
  private static final int THEME_DARK = 1;

  /** Keys for results returned by Gesture Search */
  private static final String SELECTED_ITEM_ID = "selected_item_id";
  private static final String SELECTED_ITEM_NAME = "selected_item_name";
As you can see in the code, when Gesture Search appears, we can show a recently selected country name, or nothing. Gesture Search then appears with a list of all the country names. The user can draw gestures directly on top of the list and a target item will pop up at the top. When a user taps a country name, Gesture Search exits and returns the result to the calling app. The following method is invoked for processing the user selection result, reading the Id and the name of the chosen data item.
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (resultCode == Activity.RESULT_OK) {
      switch (requestCode) {
        case GESTURE_SEARCH_ID:
          long selectedItemId = data.getLongExtra(SELECTED_ITEM_ID, -1);
          String selectedItemName = data.getStringExtra(SELECTED_ITEM_NAME);
          // Print out the Id and name of the item that is selected 
          // by the user in Gesture Search
          Log.d("GestureSearchExample", selectedItemId + ": " + selectedItemName);
To use the Gesture Search API, you must be sure Gesture Search is installed. To test this condition, catch ActivityNotFoundException as shown in the above code snippet and display a MessageBox asking the user to install Gesture Search.

You can download the sample code at

Yang Li builds interactive systems to make information easily accessible anywhere anytime. He likes watching movies and spending quality time with his family.

Posted by Scott Knaster, Editor


  1. I appear to be crashing Gesture Search. Does it support the (valid) case where there is no suggest_icon_1 column?

  2. Yes. What message are you getting in the logcat when it crashes?

  3. Do you see this gesture technology making its way beyond just Android? I personally think that Google instant provides a more robust solution simply because its faster to push a letter than to draw it

  4. Thank you for posting this. It answered lots of questions which I had.

    Android Application Development

  5. how can i download the jar file of gesture search api...i cant find it on net.plz help....i tried running this code but later realized that there is no library such as my pc
    plz help

  6. in addition when i run the code i get only the application name and hello message on emulator and the emulator do not respond to any gestures i make
    is the gesture search api different from gesture api in android 1.6 and higher version or is it the same???
    i am using sdk android sdk 1.6 for running this gesturesearchapi demo code and country provider code. do i need to use higher sdk(platform)???
    even in google api android 3.1 i can only find package and not this gesture search package.... plz give me some link to download the jar file of geaturesearch api...any minor help is welcome. thnx all

    1. did you already get the jar file of this application? if yes. would it possible for you to share it to me.?? i am currently in need to do a gesture search application like the existing one and having the jar file of this api will be a really big help for me. . ty. :)

  7. does gesture search support letters other than english alphabets???

  8. You need to install Gesture Search on the device or the emulator for the API to work.

  9. Gesture Search currently supports the English alphabet and numbers.

  10. Ola sou do Brasil (Made in Brazil)

    Estou com um grande problema, tenho uma prima que está sendo ameaçada por causa de frases obcenas que colocaream no orkut dela, que foi harckeado. estamos tentando com a google, tracar a senha ou até mesmo excluir esse orkut. O que precisar para comprovar que o orkut é da mesma temos.

    estou resolvendo isso por ela por tanto caso queira me enviar o email segue abaixo.

  11. Hi! Im an IT student. I was hoping to get an I advice from you, currently me and my THESIS partner are studying android for our THESIS (a subject where we create or either enhance application) and we chose this Gesture Search Application as our topic. and as part of this subject , we are to create a prototype of this application. Can you somehow suggest me a good tutorial or Instructions for creating a prototype for this application? Sorry, If I may bother you. It's my first time in doing an android application. Any help from you will do great for our project. Thank you!! and God bless!