Android no search activity

Android Tutorial: Adding Search to Your Apps

Search on Android is a big topic. On every device’s homescreen is the Quick Search Box by default, older devices even had a dedicated search button. With the Quick Search Box you can quickly search the web, search for apps or contacts and search within all apps that are configured for global search. Many apps also provide local search capabilities to help you find necessary information as quickly as possible.

In this two-part tutorial series I will show you how to leverage Android’s search framework. This first part shows you the basics of Android’s search framework. In the second part I am going to cover search suggestions and global search.

Local vs. global search

There are essentially two kinds of search in Android:

• local search and
• global search

Local search enables users to search content of the currently visible app. Local search is appropriate for nearly every type of app. A recipe app could offer users to search for words in the title of the recipes or within the list of ingredients. Local search is strictly limited to the app offering it and it’s results are not visible outside of the app.

Global search on the other hand makes the content also accessible from within the Quick Search Box on the home screen. Android uses multiple data source for global search and your app can be one of it. In the next screen taken on a tablet you can see the results of a Google search on the left and some results from apps or for app titles on the right.

Quick Search box search results on a tablet

The user experience for local and global search is a bit different since global search uses multiple data sources. By default it provides search results from Google, searches for installed apps or contacts on the device and it also might include results from apps that enable global search. The following screenshot of a phone shows all content that is included in the list of search results.

Sources for Android’s Quick Search Bar

For an app to be included in this list, the user must explicitly enable it. From the perspective of the user doing the search this is a very useful restriction. That way users can limit global search to include only what they really are interested in. For app developers that tend to think that their content is the stuff any user is most likely searching for, this of course is a big letdown 🙂

You should use global search only when your content is likely to be searched for from the Quick Search Box. That might be true for a friend in facebook but not necessarily for a recipe of a cooking app. I will cover configuring global search in more detail in the second part of this tutorial series.

Enabling search for your app

You always need to execute at least three steps to make your app searchable. If you want to provide search suggestions you have to add a fourth step:

1. You have to write an xml file with the search configuration
2. You have to write a search activity
3. You have to tie the former two together using the AndroidManifest.xml
4. You have to add a content provider for search suggestions — if needed

I am going to cover the first three steps in the following sections. And I am going to write about the content provider for search suggestions in the next part of this tutorial.

Configuring your search

You have to tell Android how you want your app to interact with Android’s search capabilities. This is done in an xml file. Following established practices you should name the file searchable.xml and store it in the res/xml folder of your app.

The least you have to configure is the label for the search box — even though the label is only relevant for global search. You also should always add a hint as Android displays this text within the form field. You can use this to guide the user.

There are many more attributes. I will cover those for global search in the next part of this tutorial and for voice search later on. You can find a list of all attributes on Android’s reference page.

Adding a SearchActivity

Whenever a users performs a search, Android calls an activity to process the search query. The intent used to call the activity contains the query string as an intent extra and uses the value of the static field Intent.ANDROID_SEARCH . Since you configure which activity to use for search (see next section), Android calls your activity with an explicit intent.

Most often your search activity will extend ListActivity to present a list of results to the user:

So why did I include the onNewIntent() method? I did this because of Android back stack. By default Android adds every new activity on top of the activity stack. That way the functionality of the back key is supported. If a user presses the back button, Android closes the top-most activity and resumes the next activity on the stack.

Now consider a typical search behavior. The user searches for a word and has a look at the results. Oftentimes she either did not find what she were looking for or she wants to search additional information. So she clicks the search key again, enters the new search phrase and selects a suggestion. Thus a new instance of your search activity would end up on top of your previous one. The activity stack would contain the search activity twice and users would have to hit the back key twice to get back to where they were before starting the search. Which probably is not what you want. Normally you want your search activity to be on the top of the stack only once.

That’s why you should declare the activity as singleTop . That way it is only once on your stack. Should a user start a new search from within your search activity, Android would recycle the instance and call the method onNewIntent() with the new search intent as its parameter. Since the old intent is still stored within your activity, you should always call setIntent(newIntent) within your onNewIntent() method to replace the original intent with the new one.

Tying everything together in your manifest file

To make search work you have to configure it within your project’s AndroidManifest.xml file. These are the things you have to put in there:

• Your search activity
• The intent used for search
• The launch mode for your activity
• The meta-data pointing to your searchable.xml
• Further meta-data to define which activity to use for search.

The following code shows a snippet of a typical configuration.

Your search activity must include the intent used for search

Android uses the value android.intent.action.SEARCH for the action within the intent when calling your search activity. So you must include this string within your activity’s intent filters. Otherwise your activity would be ignored.

The meta-data pointing to your searchable.xml

As described above you have to have an xml file to configure your search. But Android neither knows the name of this file nor its location. So Google came up with a meta-data element to point to this file.

Additional meta-data to define which activity to use for search.

Finally Android needs to know which activity to call when a search query is submitted. Again you have to use a meta-data element.

Handling search yourself

It’s important to present your user an obvious way to start search. Even when most devices had a dedicated search button you still were better of, when you added a way to manually start a search. For one users might not be familiar with the search button. But even if they know of the button they simply might not know that your app is capable of search. Thus you have to make it obvious that your app is searchable.

With the introduction of Honeycomb and Ice Cream Sandwich Android devices no longer have a search button. Instead the preferred way to present a search option is to show a search button or the search widget in the action bar.

This pattern has become common quickly and you should use an action bar with a search button even on older devices. See for example the following screenshot. It shows Gigbeat — one of my favorite apps — on an Android 2.2 device.

Action Bar with search on an Android 2.2 device

When the user wants to search, you have to call the search dialog from within your activity. This is done by calling onSearchRequested() . This method is part of Android’s Activity class and calls startSearch() which I will cover in a few moments.

Android’s search framework uses onSearchRequested() when the dialog should be started. Thus you should use it as well, even though it might appear odd to call a callback method directly.

Adding specific data to the search

The default search behavior is not always sufficient. First of all it only starts a local search. Most often that’s appropriate for your app, but sometimes a global search is what you need. And secondly you might want to add some specific data to the search that might depend on the state your app is in or that is specific for starting the search from this Activity only.

In these cases you have to override onSearchRequested() and call startSearch() yourself.

The method startSearch() takes four parameters which I explain in the table below.

The parameters for the startSearch() method

Parameter	Type	Meaning
initialQuery	String	A string with which to preload the search box.
selectInitialQuery	boolean	The flag that decides whether the content of the search box (that is the initialQuery) should be selected. If set to true any text entered overrides the initialQuery.
appSearchData	Bundle	Additional data to pass to the search activity.
globalSearch	boolean	The flag that decides whether global search should be used.

The call to startSearch() of the base class Activity uses the values null , false , null , false — which means it is a local search without any further data.

Enabling your app for voice search

To enable voice search you only have to add a few lines to your search configuration.

As you can see in the following screenshot, enabling voice search causes Android to display a microphone next to the search dialog.

Enabled voice search with microphone symbol

As soon as you click the microphone the well-known voice input dialog pops up.

Voice search dialog

But not all Android devices might support voice search. If the device of a user has no voice search capabilities your voice search configuration will be ignored and the microphone symbol will not be displayed.

There are four attributes to the searchable element that deal with voice search but two should suffice in most cases.

The only obligatory attribute for voice search is android:voiceSearchMode . This attribute must contain showVoiceSearchButton , if you want to use voice search. Separated by a pipe («|») it needs a second value which determines the type of search: launchWebSearch or launchRecognizer .

It’s best to use launchRecognizer here, because the other value would use a web search — which normally wouldn’t yield the results appropriate for your app.

So the configuration should look like this:

The second important attribute is android:voiceLanguageModel . For this attribute also two types are possible: web_search and free_form .

Normally web_search should work best here — it is ideal for search like phrases where a user often won’t use correct sentences. The value free_form is more appropriate for voice input in other apps like mail or SMS that take larger chunks of well-formed text. See the developers blog post about Google’s speech input API.

One word of advice concerning voice search though: Voice search only works if the user of the app has access to the internet. If the user has no connection to the internet, Android will display an error dialog:

Voice search with connection problem

Wrapping up

In this part of the tutorial I have shown you how to use Android’s search framework. You have to add some configuration and add a search activity. But all in all, it’s not too difficult to add decent search capabilities to your app.

Even adding voice search requires just two lines of configuration — though you should know its limitations.

In the next part of this tutorial I will cover how to add search suggestions to your app and to the Quick Search Box on Android’s homescreen. Stay tuned!

Wolfram Rittmeyer lives in Germany and has been developing with Java for many years.

He has been interested in Android for quite a while and has been blogging about all kind of topics around Android.

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Creating a Search Interface

In this document

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Related samples

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When you’re ready to add search functionality to your application, Android helps you implement the user interface with either a search dialog that appears at the top of the activity window or a search widget that you can insert in your layout. Both the search dialog and the widget can deliver the user’s search query to a specific activity in your application. This way, the user can initiate a search from any activity where the search dialog or widget is available, and the system starts the appropriate activity to perform the search and present results.

Other features available for the search dialog and widget include:

• Voice search
• Search suggestions based on recent queries
• Search suggestions that match actual results in your application data

This guide shows you how to set up your application to provide a search interface that’s assisted by the Android system to deliver search queries, using either the search dialog or the search widget.

The Basics

Figure 1. Screenshot of an application’s search dialog.

Before you begin, you should decide whether you’ll implement your search interface using the search dialog or the search widget. Both provide the same search features, but in slightly different ways:

The search dialog is a UI component that’s controlled by the Android system. When activated by the user, the search dialog appears at the top of the activity, as shown in figure 1.

The Android system controls all events in the search dialog. When the user submits a query, the system delivers the query to the activity that you specify to handle searches. The dialog can also provide search suggestions while the user types.

The search widget is an instance of SearchView that you can place anywhere in your layout. By default, the search widget behaves like a standard EditText widget and doesn’t do anything, but you can configure it so that the Android system handles all input events, delivers queries to the appropriate activity, and provides search suggestions (just like the search dialog). However, the search widget is available only in Android 3.0 (API Level 11) and higher.

Note: If you want, you can handle all user input into the search widget yourself, using various callback methods and listeners. This document, however, focuses on how to integrate the search widget with the system for an assisted search implementation. If you want to handle all user input yourself, read the reference documentation for SearchView and its nested interfaces.

When the user executes a search from the search dialog or a search widget, the system creates an Intent and stores the user query in it. The system then starts the activity that you’ve declared to handle searches (the «searchable activity») and delivers it the intent. To set up your application for this kind of assisted search, you need the following:

A searchable configuration

An XML file that configures some settings for the search dialog or widget. It includes settings for features such as voice search, search suggestion, and hint text for the search box.

A searchable activity

The Activity that receives the search query, searches your data, and displays the search results.

A search interface, provided by either:

The search dialog

By default, the search dialog is hidden, but appears at the top of the screen when you call onSearchRequested() (when the user presses your Search button).

Using the search widget allows you to put the search box anywhere in your activity. Instead of putting it in your activity layout, you should usually use SearchView as an action view in the Action Bar.

The rest of this document shows you how to create the searchable configuration, searchable activity, and implement a search interface with either the search dialog or search widget.

Creating a Searchable Configuration

The first thing you need is an XML file called the searchable configuration. It configures certain UI aspects of the search dialog or widget and defines how features such as suggestions and voice search behave. This file is traditionally named searchable.xml and must be saved in the res/xml/ project directory.

Note: The system uses this file to instantiate a SearchableInfo object, but you cannot create this object yourself at runtime—you must declare the searchable configuration in XML.

The searchable configuration file must include the element as the root node and specify one or more attributes. For example:

The android:label attribute is the only required attribute. It points to a string resource, which should be the application name. This label isn’t actually visible to the user until you enable search suggestions for Quick Search Box. At that point, this label is visible in the list of Searchable items in the system Settings.

Though it’s not required, we recommend that you always include the android:hint attribute, which provides a hint string in the search box before users enters a query. The hint is important because it provides important clues to users about what they can search.

Tip: For consistency among other Android applications, you should format the string for android:hint as «Search «. For example, «Search songs and artists» or «Search YouTube».

The element accepts several other attributes. However, you don’t need most attributes until you add features such as search suggestions and voice search. For detailed information about the searchable configuration file, see the Searchable Configuration reference document.

Creating a Searchable Activity

A searchable activity is the Activity in your application that performs searches based on a query string and presents the search results.

When the user executes a search in the search dialog or widget, the system starts your searchable activity and delivers it the search query in an Intent with the ACTION_SEARCH action. Your searchable activity retrieves the query from the intent’s QUERY extra, then searches your data and presents the results.

Because you may include the search dialog or widget in any other activity in your application, the system must know which activity is your searchable activity, so it can properly deliver the search query. So, you must first declare your searchable activity in the Android manifest file.

Declaring a searchable activity

If you don’t have one already, create an Activity that will perform searches and present results. You don’t need to implement the search functionality yet—just create an activity that you can declare in the manifest. Inside the manifest’s element:

1. Declare the activity to accept the ACTION_SEARCH intent, in an element.
2. Specify the searchable configuration to use, in a element.

The element must include the android:name attribute with a value of «android.app.searchable» and the android:resource attribute with a reference to the searchable configuration file (in this example, it refers to the res/xml/searchable.xml file).

Note: The does not need a with the DEFAULT value (which you usually see in elements), because the system delivers the ACTION_SEARCH intent explicitly to your searchable activity, using its component name.

Performing a search

Once you have declared your searchable activity in the manifest, performing a search in your searchable activity involves three steps:

Traditionally, your search results should be presented in a ListView , so you might want your searchable activity to extend ListActivity . It includes a default layout with a single ListView and provides several convenience methods for working with the ListView .

Receiving the query

When a user executes a search from the search dialog or widget, the system starts your searchable activity and sends it a ACTION_SEARCH intent. This intent carries the search query in the QUERY string extra. You must check for this intent when the activity starts and extract the string. For example, here’s how you can get the search query when your searchable activity starts:

The QUERY string is always included with the ACTION_SEARCH intent. In this example, the query is retrieved and passed to a local doMySearch() method where the actual search operation is done.

Searching your data

The process of storing and searching your data is unique to your application. You can store and search your data in many ways, but this guide does not show you how to store your data and search it. Storing and searching your data is something you should carefully consider in terms of your needs and your data format. However, here are some tips you might be able to apply:

• If your data is stored in a SQLite database on the device, performing a full-text search (using FTS3, rather than a LIKE query) can provide a more robust search across text data and can produce results significantly faster. See sqlite.org for information about FTS3 and the SQLiteDatabase class for information about SQLite on Android. Also look at the Searchable Dictionary sample application to see a complete SQLite implementation that performs searches with FTS3.
• If your data is stored online, then the perceived search performance might be inhibited by the user’s data connection. You might want to display a spinning progress wheel until your search returns. See android.net for a reference of network APIs and Creating a Progress Dialog for information about how to display a progress wheel.

About Adapters

An Adapter binds each item from a set of data into a View object. When the Adapter is applied to a ListView , each piece of data is inserted as an individual view into the list. Adapter is just an interface, so implementations such as CursorAdapter (for binding data from a Cursor ) are needed. If none of the existing implementations work for your data, then you can implement your own from BaseAdapter . Install the SDK Samples package for API Level 4 to see the original version of the Searchable Dictionary, which creates a custom adapter to read data from a file.

Regardless of where your data lives and how you search it, we recommend that you return search results to your searchable activity with an Adapter . This way, you can easily present all the search results in a ListView . If your data comes from a SQLite database query, you can apply your results to a ListView using a CursorAdapter . If your data comes in some other type of format, then you can create an extension of BaseAdapter .

Presenting the results

As discussed above, the recommended UI for your search results is a ListView , so you might want your searchable activity to extend ListActivity . You can then call setListAdapter() , passing it an Adapter that is bound to your data. This injects all the search results into the activity ListView .

For more help presenting your results in a list, see the ListActivity documentation.

Also see the Searchable Dictionary sample for an a complete demonstration of how to search an SQLite database and use an Adapter to provide results in a ListView .

Using the Search Dialog

Should I use the search dialog or the widget?

The answer depends mostly on whether you are developing for Android 3.0 (API Level 11 or higher), because the SearchView widget was introduced in Android 3.0. So, if you are developing your application for a version of Android lower than 3.0, the search widget is not an option and you should use the search dialog to implement your search interface.

If you are developing for Android 3.0 or higher, then the decision depends more on your needs. In most cases, we recommend that you use the search widget as an «action view» in the Action Bar. However, it might not be an option for you to put the search widget in the Action Bar for some reason (perhaps there’s not enough space or you don’t use the Action Bar). So, you might instead want to put the search widget somewhere in your activity layout. And if all else fails, you can still use the search dialog if you prefer to keep the search box hidden. In fact, you might want to offer both the dialog and the widget in some cases. For more information about the widget, skip to Using the Search Widget.

The search dialog provides a floating search box at the top of the screen, with the application icon on the left. The search dialog can provide search suggestions as the user types and, when the user executes a search, the system sends the search query to a searchable activity that performs the search. However, if you are developing your application for devices running Android 3.0, you should consider using the search widget instead (see the side box).

The search dialog is always hidden by default, until the user activates it. Your application can activate the search dialog by calling onSearchRequested() . However, this method doesn’t work until you enable the search dialog for the activity.

To enable the search dialog, you must indicate to the system which searchable activity should receive search queries from the search dialog, in order to perform searches. For example, in the previous section about Creating a Searchable Activity, a searchable activity named SearchableActivity was created. If you want a separate activity, named OtherActivity , to show the search dialog and deliver searches to SearchableActivity , you must declare in the manifest that SearchableActivity is the searchable activity to use for the search dialog in OtherActivity .

For example, here is the declaration for both a searchable activity, SearchableActivity , and another activity, OtherActivity , which uses SearchableActivity to perform searches executed from its search dialog:

Because the OtherActivity now includes a element to declare which searchable activity to use for searches, the activity has enabled the search dialog. While the user is in this activity, the onSearchRequested() method activates the search dialog. When the user executes the search, the system starts SearchableActivity and delivers it the ACTION_SEARCH intent.

Note: The searchable activity itself provides the search dialog by default, so you don’t need to add this declaration to SearchableActivity .

With the search dialog now enabled for your activities, your application is ready to perform searches.

Invoking the search dialog

Although some devices provide a dedicated Search button, the behavior of the button may vary between devices and many devices do not provide a Search button at all. So when using the search dialog, you must provide a search button in your UI that activates the search dialog by calling onSearchRequested() .

For instance, you should add a Search button in your Options Menu or UI layout that calls onSearchRequested() . For consistency with the Android system and other apps, you should label your button with the Android Search icon that’s available from the Action Bar Icon Pack.

Note: If your app uses the action bar, then you should not use the search dialog for your search interface. Instead, use the search widget as a collapsible view in the action bar.

You can also enable «type-to-search» functionality, which activates the search dialog when the user starts typing on the keyboard—the keystrokes are inserted into the search dialog. You can enable type-to-search in your activity by calling setDefaultKeyMode ( DEFAULT_KEYS_SEARCH_LOCAL ) during your activity’s onCreate() method.

The impact of the search dialog on your activity lifecycle

The search dialog is a Dialog that floats at the top of the screen. It does not cause any change in the activity stack, so when the search dialog appears, no lifecycle methods (such as onPause() ) are called. Your activity just loses input focus, as input focus is given to the search dialog.

If you want to be notified when the search dialog is activated, override the onSearchRequested() method. When the system calls this method, it is an indication that your activity has lost input focus to the search dialog, so you can do any work appropriate for the event (such as pause a game). Unless you are passing search context data (discussed below), you should end the method by calling the super class implementation. For example:

If the user cancels search by pressing the Back button, the search dialog closes and the activity regains input focus. You can register to be notified when the search dialog is closed with setOnDismissListener() and/or setOnCancelListener() . You should need to register only the OnDismissListener , because it is called every time the search dialog closes. The OnCancelListener only pertains to events in which the user explicitly exited the search dialog, so it is not called when a search is executed (in which case, the search dialog naturally disappears).

If the current activity is not the searchable activity, then the normal activity lifecycle events are triggered once the user executes a search (the current activity receives onPause() and so forth, as described in the Activities document). If, however, the current activity is the searchable activity, then one of two things happens:

1. By default, the searchable activity receives the ACTION_SEARCH intent with a call to onCreate() and a new instance of the activity is brought to the top of the activity stack. There are now two instances of your searchable activity in the activity stack (so pressing the Back button goes back to the previous instance of the searchable activity, rather than exiting the searchable activity).
2. If you set android:launchMode to «singleTop» , then the searchable activity receives the ACTION_SEARCH intent with a call to onNewIntent(Intent) , passing the new ACTION_SEARCH intent here. For example, here’s how you might handle this case, in which the searchable activity’s launch mode is «singleTop» :

Compared to the example code in the section about Performing a Search, all the code to handle the search intent is now in the handleIntent() method, so that both onCreate() and onNewIntent() can execute it.

When the system calls onNewIntent(Intent) , the activity has not been restarted, so the getIntent() method returns the same intent that was received with onCreate() . This is why you should call setIntent(Intent) inside onNewIntent(Intent) (so that the intent saved by the activity is updated in case you call getIntent() in the future).

The second scenario using «singleTop» launch mode is usually ideal, because chances are good that once a search is done, the user will perform additional searches and it’s a bad experience if your application creates multiple instances of the searchable activity. So, we recommend that you set your searchable activity to «singleTop» launch mode in the application manifest. For example:

Passing search context data

In some cases, you can make necessary refinements to the search query inside the searchable activity, for every search made. However, if you want to refine your search criteria based on the activity from which the user is performing a search, you can provide additional data in the intent that the system sends to your searchable activity. You can pass the additional data in the APP_DATA Bundle , which is included in the ACTION_SEARCH intent.

To pass this kind of data to your searchable activity, override the onSearchRequested() method for the activity from which the user can perform a search, create a Bundle with the additional data, and call startSearch() to activate the search dialog. For example:

Returning «true» indicates that you have successfully handled this callback event and called startSearch() to activate the search dialog. Once the user submits a query, it’s delivered to your searchable activity along with the data you’ve added. You can extract the extra data from the APP_DATA Bundle to refine the search. For example:

Caution: Never call the startSearch() method from outside the onSearchRequested() callback method. To activate the search dialog in your activity, always call onSearchRequested() . Otherwise, onSearchRequested() is not called and customizations (such as the addition of appData in the above example) are missed.

Using the Search Widget

Figure 2. The SearchView widget as an «action view» in the Action Bar.

The SearchView widget is available in Android 3.0 and higher. If you’re developing your application for Android 3.0 and have decided to use the search widget, we recommend that you insert the search widget as an action view in the Action Bar, instead of using the search dialog (and instead of placing the search widget in your activity layout). For example, figure 2 shows the search widget in the Action Bar.

The search widget provides the same functionality as the search dialog. It starts the appropriate activity when the user executes a search, and it can provide search suggestions and perform voice search.

Note: When you use the search widget as an action view, you still might need to support using the search dialog, for cases in which the search widget does not fit in the Action Bar. See the following section about Using both the widget and the dialog.

Configuring the search widget

After you’ve created a searchable configuration and a searchable activity, as discussed above, you need to enable assisted search for each SearchView . You can do so by calling setSearchableInfo() and passing it the SearchableInfo object that represents your searchable configuration.

You can get a reference to the SearchableInfo by calling getSearchableInfo() on SearchManager .

For example, if you’re using a SearchView as an action view in the Action Bar, you should enable the widget during the onCreateOptionsMenu() callback:

That’s all you need. The search widget is now configured and the system will deliver search queries to your searchable activity. You can also enable search suggestions for the search widget.

Note: If you want to handle all user input yourself, you can do so with some callback methods and event listeners. For more information, see the reference documentation for SearchView and its nested interfaces for the appropriate event listeners.

For more information about action views in the Action Bar, read the Action Bar developer guide (which includes sample code for adding a search widget as an action view).

Other search widget features

The SearchView widget allows for a few additional features you might want:

A submit button By default, there’s no button to submit a search query, so the user must press the «Return» key on the keyboard to initiate a search. You can add a «submit» button by calling setSubmitButtonEnabled(true) . Query refinement for search suggestions When you’ve enabled search suggestions, you usually expect users to simply select a suggestion, but they might also want to refine the suggested search query. You can add a button alongside each suggestion that inserts the suggestion in the search box for refinement by the user, by calling setQueryRefinementEnabled(true) . The ability to toggle the search box visibility By default, the search widget is «iconified,» meaning that it is represented only by a search icon (a magnifying glass), and expands to show the search box when the user touches it. As shown above, you can show the search box by default, by calling setIconifiedByDefault(false) . You can also toggle the search widget appearance by calling setIconified() .

There are several other APIs in the SearchView class that allow you to customize the search widget. However, most of them are used only when you handle all user input yourself, instead of using the Android system to deliver search queries and display search suggestions.

Using both the widget and the dialog

If you insert the search widget in the Action Bar as an action view, and you enable it to appear in the Action Bar «if there is room» (by setting android:showAsAction=»ifRoom» ), then there is a chance that the search widget will not appear as an action view, but the menu item will appear in the overflow menu. For example, when your application runs on a smaller screen, there might not be enough room in the Action Bar to display the search widget along with other action items or navigation elements, so the menu item will instead appear in the overflow menu. When placed in the overflow menu, the item works like an ordinary menu item and does not display the action view (the search widget).

To handle this situation, the menu item to which you’ve attached the search widget should activate the search dialog when the user selects it from the overflow menu. In order for it to do so, you must implement onOptionsItemSelected() to handle the «Search» menu item and open the search dialog by calling onSearchRequested() .

For more information about how items in the Action Bar work and how to handle this situation, see the Action Bar developer guide.

Also see the Searchable Dictionary for an example implementation using both the dialog and the widget.

Adding Voice Search

You can add voice search functionality to your search dialog or widget by adding the android:voiceSearchMode attribute to your searchable configuration. This adds a voice search button that launches a voice prompt. When the user has finished speaking, the transcribed search query is sent to your searchable activity.

The value showVoiceSearchButton is required to enable voice search, while the second value, launchRecognizer , specifies that the voice search button should launch a recognizer that returns the transcribed text to the searchable activity.

You can provide additional attributes to specify the voice search behavior, such as the language to be expected and the maximum number of results to return. See the Searchable Configuration reference for more information about the available attributes.

Note: Carefully consider whether voice search is appropriate for your application. All searches performed with the voice search button are immediately sent to your searchable activity without a chance for the user to review the transcribed query. Sufficiently test the voice recognition and ensure that it understands the types of queries that the user might submit inside your application.

Adding Search Suggestions

Figure 3. Screenshot of a search dialog with custom search suggestions.

Both the search dialog and the search widget can provide search suggestions as the user types, with assistance from the Android system. The system manages the list of suggestions and handles the event when the user selects a suggestion.

You can provide two kinds of search suggestions:

Recent query search suggestions These suggestions are simply words that the user previously used as search queries in your application.

Custom search suggestions These are search suggestions that you provide from your own data source, to help users immediately select the correct spelling or item they are searching for. Figure 3 shows an example of custom suggestions for a dictionary application—the user can select a suggestion to instantly go to the definition.

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