This lesson teaches you to
You should also read:
Beginning in Android 3.0, using the SearchView
widget as an item in
the app bar is the preferred way to provide search in your app. Like with all items in
the app bar, you can define the SearchView
to show at all times, only
when there is room, or as a collapsible action, which displays the SearchView
as an icon initially, then takes up the entire app bar as a search
field when the user clicks the icon.
Note: Later in this class, you will learn how to make your
app compatible down to Android 2.1 (API level 7) for devices that do not support
SearchView
.
Add the Search View to the App Bar
To add a SearchView
widget to the app bar, create a file named
res/menu/options_menu.xml
in your project and add the following code to the file.
This code defines how to create the search item, such as the icon to use and the title of the
item. The collapseActionView
attribute allows your SearchView
to expand to take up the whole app bar and collapse back down into a
normal app bar item when not in use. Because of the limited app bar space on handset devices,
using the collapsibleActionView
attribute is recommended to provide a better
user experience.
<?xml version="1.0" encoding="utf-8"?> <menu xmlns:android="http://schemas.android.com/apk/res/android"> <item android:id="@+id/search" android:title="@string/search_title" android:icon="@drawable/ic_search" android:showAsAction="collapseActionView|ifRoom" android:actionViewClass="android.widget.SearchView" /> </menu>
Note: If you already have an existing XML file for your menu
items, you can add the <item>
element to that file instead.
To display the SearchView
in the app bar, inflate the XML menu
resource (res/menu/options_menu.xml
) in the onCreateOptionsMenu()
method of your activity:
@Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.options_menu, menu); return true; }
If you run your app now, the SearchView
appears in your app's app
bar, but it isn't functional. You now need to define how the SearchView
behaves.
Create a Searchable Configuration
A searchable
configuration defines how the SearchView
behaves and is defined in a
res/xml/searchable.xml
file. At a minimum, a searchable configuration must contain
an android:label
attribute that has the same value as the
android:label
attribute of the <application> or
<activity> element in your Android manifest.
However, we also recommend adding an android:hint
attribute to give the user an idea of what to enter into the search
box:
<?xml version="1.0" encoding="utf-8"?> <searchable xmlns:android="http://schemas.android.com/apk/res/android" android:label="@string/app_name" android:hint="@string/search_hint" />
In your application's manifest file, declare a
<meta-data>
element that points to the res/xml/searchable.xml
file,
so that your application knows where to find it. Declare the element in an <activity>
that you want to display the SearchView
in:
<activity ... > ... <meta-data android:name="android.app.searchable" android:resource="@xml/searchable" /> </activity>
In the onCreateOptionsMenu()
method that you
created before, associate the searchable configuration with the SearchView
by calling setSearchableInfo(SearchableInfo)
:
@Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.options_menu, menu); // Associate searchable configuration with the SearchView SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE); SearchView searchView = (SearchView) menu.findItem(R.id.search).getActionView(); searchView.setSearchableInfo( searchManager.getSearchableInfo(getComponentName())); return true; }
The call to getSearchableInfo()
obtains a
SearchableInfo
object that is created from the searchable configuration XML
file. When the searchable configuration is correctly associated with your SearchView
, the SearchView
starts an activity with the
ACTION_SEARCH
intent when a user submits a query. You now need an
activity that can filter for this intent and handle the search query.
Create a Searchable Activity
A SearchView
tries to start an activity with the ACTION_SEARCH
when a user submits a search query. A searchable activity
filters for the ACTION_SEARCH
intent and searches for the query in
some sort of data set. To create a searchable activity, declare an activity of your choice to
filter for the ACTION_SEARCH
intent:
<activity android:name=".SearchResultsActivity" ... > ... <intent-filter> <action android:name="android.intent.action.SEARCH" /> </intent-filter> ... </activity>
In your searchable activity, handle the ACTION_SEARCH
intent by
checking for it in your onCreate()
method.
Note: If your searchable activity launches in single top mode
(android:launchMode="singleTop"
), also handle the ACTION_SEARCH
intent in the onNewIntent()
method. In single top mode, only one instance of your activity is created and
subsequent calls to start your activity do not create a new activity on the
stack. This launch mode is useful so users can perform searches from the same activity
without creating a new activity instance every time.
public class SearchResultsActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { ... handleIntent(getIntent()); } @Override protected void onNewIntent(Intent intent) { ... handleIntent(intent); } private void handleIntent(Intent intent) { if (Intent.ACTION_SEARCH.equals(intent.getAction())) { String query = intent.getStringExtra(SearchManager.QUERY); //use the query to search your data somehow } } ... }
If you run your app now, the SearchView
can accept the user's query and
start your searchable activity with the ACTION_SEARCH
intent. It
is now up to you to figure out how to store and search your data given a query.