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widget as an item in the action bar is the preferred way to provide search in your app. Like with all items in the action bar, you can define the
to show at all times, only when there is room, or as a collapsible action, which displays the
as an icon initially, then takes up the entire action 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 .
To add a widget to the action 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 to expand to take up the whole action bar and collapse back down into a normal action bar item when not in use. Because of the limited action bar space on handset devices, using the
collapsibleActionView
attribute is recommended to provide a better user experience. http://blog.sina.com.cn/mtkshanghai
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 in the action bar, inflate the XML menu resource (
res/menu/options_menu.xml
) in the method of your activity:
@Overridepublic boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.options_menu, menu); return true;}
If you run your app now, the appears in your app's action bar, but it isn't functional. You now need to define how the
behaves.
A defines how the 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 or 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:
In your application's manifest file, declare a 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 in:
...
In the method that you created before, associate the searchable configuration with the
by calling
:
@Overridepublic 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 obtains a
object that is created from the searchable configuration XML file. When the searchable configuration is correctly associated with your
, the
starts an activity with the
intent when a user submits a query. You now need an activity that can filter for this intent and handle the search query.
A tries to start an activity with the
when a user submits a search query. A searchable activity filters for the 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
intent:
... ...
In your searchable activity, handle the intent by checking for it in your
method.
Note: If your searchable activity launches in single top mode (android:launchMode="singleTop"
), also handle the intent in the
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 can accept the user's query and start your searchable activity with the
intent. It is now up to you to figure out how to store and search your data given a query.
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