When using the Android search dialog or search widget, you can provide custom search suggestions that are created from data in your app. For example, if your app is a dictionary, you can suggest words from the dictionary that match the text entered in the search field before the user finishes entering their query. These suggestions are valuable because they can effectively predict what the user wants and provide instant access to it. Figure 1 shows an example of a search dialog with custom suggestions.
Once you provide custom suggestions, you can also make them available to the system-wide Quick Search Box, providing access to your content from outside your app.
Before you add custom suggestions, implement the Android search dialog or a search widget for searches in your app. See Create a search interface and Content providers.
The basics
When the user selects a custom suggestion, the system sends an
Intent
to your
searchable activity. Unlike a normal search query that sends an intent with the
ACTION_SEARCH
action, you can instead define your custom suggestions to use
ACTION_VIEW
—or
any other intent action—and also include data that's relevant to the
selected suggestion. In the dictionary example, when the user selects a
suggestion, the app can immediately open the definition for that word, instead
of searching the dictionary for matches.
To provide custom suggestions, perform the following steps:
- Implement a basic searchable activity, as described in Create a search interface.
- Modify the searchable configuration with information about the content provider that provides custom suggestions.
- Build a table, such as in a
SQLiteDatabase
, for your suggestions and format the table with required columns. - Create a content provider that has access to your suggestions table and declare the provider in your manifest.
- Declare the type of
Intent
to be sent when the user selects a suggestion, including a custom action and custom data.
Just as the Android system displays the search dialog, it also displays your search suggestions. You need a content provider from which the system can retrieve your suggestions. Read Content providers to learn how to create a content provider.
When the system identifies that your activity is searchable and provides search suggestions, the following procedure takes place when the user enters a query:
- The system takes the search query text—meaning, whatever is entered so far—and performs a query to your content provider that manages your suggestions.
- Your content provider returns a
Cursor
that points to all suggestions that are relevant to the search query text. - The system displays the list of suggestions provided by the
Cursor
.
Once the custom suggestions are displayed, the following might happen:
- If the user enters another letter or changes the query in any way, the preceding steps repeat and the suggestion list updates accordingly.
- If the user executes the search, the suggestions are ignored and the
search is delivered to your searchable activity using the normal
ACTION_SEARCH
intent. - If the user selects a suggestion, an intent is sent to your searchable activity, carrying a custom action and custom data so that your app can open the suggested content.
Modify the searchable configuration
To add support for custom suggestions, add the
android:searchSuggestAuthority
attribute to the
<searchable>
element in your searchable configuration file,
as shown in the following example:
<?xml version="1.0" encoding="utf-8"?> <searchable xmlns:android="http://schemas.android.com/apk/res/android" android:label="@string/app_label" android:hint="@string/search_hint" android:searchSuggestAuthority="com.example.MyCustomSuggestionProvider"> </searchable>
You might need additional attributes, depending on the type of intent you attach to each suggestion and how you want to format queries to your content provider. The other optional attributes are discussed in the following sections.
Create a content provider
To create a content provider for custom suggestions, first see
Content providers
to learn how to create a content provider. A content provider for custom
suggestions is similar to any other content provider. However, for each
suggestion you provide, the respective row in the Cursor
must
include specific columns that the system understands and uses to format the
suggestions.
When the user enters text in the search dialog or search widget, the system
queries your content provider for suggestions by calling
query()
each time a letter is entered. In your implementation of query()
,
your content provider must search your suggestion data and return a
Cursor
that points to the rows that it determines are good
suggestions.
Details about creating a content provider for custom suggestions are discussed in the following two sections:
- Handle the suggestion query
- How the system sends requests to your content provider and how to handle them.
- Build a suggestion table
- How to define the columns that the system expects in the
Cursor
returned with each query.
Handle the suggestion query
When the system requests suggestions from your content provider, it calls
your content provider's query()
method. Implement this method to
search your suggestion data and return a Cursor
pointing to the
suggestions you deem relevant.
Here's a summary of the parameters the system passes to your
query()
method, listed in order:
uri
Always a content
Uri
, formatted as follows:content://your.authority/optional.suggest.path/
SUGGEST_URI_PATH_QUERY
The default behavior is for the system to pass this URI and append the query text to it:
content://your.authority/optional.suggest.path/
SUGGEST_URI_PATH_QUERY
/puppiesThe query text on the end is encoded using URI encoding rules, so you might need to decode it before performing a search.
The
optional.suggest.path
portion is only included in the URI if you set such a path in your searchable configuration file with theandroid:searchSuggestPath
attribute. It's only necessary if you use the same content provider for multiple searchable activities. If this is the case, disambiguate the source of the suggestion query.projection
- Always null.
selection
- The value provided in the
android:searchSuggestSelection
attribute of your searchable configuration file, or null if you don't declare theandroid:searchSuggestSelection
attribute. The following section discusses this further.selectionArgs
- Contains the search query as the first and only element of the array if you declare the
android:searchSuggestSelection
attribute in your searchable configuration. If you don't declareandroid:searchSuggestSelection
, then this parameter is null. The following section discusses this further.sortOrder
- Always null.
The system can send you the search query text in two ways. The default way is
for the query text to be included as the last path of the content URI passed in
the uri
parameter. However, if you include a selection value in
your searchable configuration's android:searchSuggestSelection
attribute, then the query text instead passes as the first element of the
selectionArgs
string array. These two options are described
next.
Get the query in the Uri
By default, the query is appended as the last segment of the uri
parameter—a Uri
object. To retrieve the query text in this
case, use
getLastPathSegment()
,
as shown in the following example:
Kotlin
val query: String = uri.lastPathSegment.toLowerCase()
Java
String query = uri.getLastPathSegment().toLowerCase();
This returns the last segment of the Uri
, which is the query
text the user enters.
Get the query in the selection arguments
Instead of using the URI, it might make more sense for your
query()
method to receive everything it needs to perform the
look-up, and you might want the selection
and
selectionArgs
parameters to carry the appropriate values. In this
case, add the android:searchSuggestSelection
attribute to your
searchable configuration with your SQLite selection string. In the selection
string, include a question mark (?) as a placeholder for the actual
search query. The system calls query()
with the selection string as
the selection
parameter and the search query as the first element
in the selectionArgs
array.
For example, here's how you might form the
android:searchSuggestSelection
attribute to create a full-text
search statement:
<?xml version="1.0" encoding="utf-8"?> <searchable xmlns:android="http://schemas.android.com/apk/res/android" android:label="@string/app_label" android:hint="@string/search_hint" android:searchSuggestAuthority="com.example.MyCustomSuggestionProvider" android:searchSuggestIntentAction="android.intent.action.VIEW" android:searchSuggestSelection="word MATCH ?"> </searchable>
With this configuration, your query()
method delivers the
selection
parameter as "word MATCH ?"
and the
selectionArgs
parameter as the search query. When you pass these to
a SQLite
query()
method, as their respective arguments, they are synthesized
together—meaning, the question mark is replaced with the query text. If
you receive suggestion queries this way and need to add wildcards to the query
text, append or prefix them to the selectionArgs
parameter, because
this value is wrapped in quotes and inserted in place of the question mark.
Another attribute in the preceding example is
android:searchSuggestIntentAction
, which defines the intent action
sent with each intent when the user selects a suggestion. This is discussed
further in the Declare an intent for
suggestions section.
Build a suggestion table
When you return suggestions to the system with a Cursor
, the
system expects specific columns in each row. Regardless of whether you store
your suggestion data in a SQLite database on the device, a database on a web
server, or another format on the device or web, format the suggestions as rows
in a table and present them with a Cursor
.
The system understands several columns, but only two of them are required:
_ID
- A unique integer row ID for each suggestion. The system requires this to
present suggestions in a
ListView
. SUGGEST_COLUMN_TEXT_1
- The string that is presented as a suggestion.
The following columns are all optional. Most are discussed further in the following sections.
SUGGEST_COLUMN_TEXT_2
- A string. If your
Cursor
includes this column, then all suggestions are provided in a two-line format. The string in this column is displayed as a second, smaller line of text below the primary suggestion text. It can be null or empty to indicate no secondary text. SUGGEST_COLUMN_ICON_1
- A drawable resource, content, or file URI string. If your
Cursor
includes this column, then all suggestions are provided in an icon-plus-text format with the drawable icon on the left side. This can be null or zero to indicate no icon in this row. SUGGEST_COLUMN_ICON_2
- A drawable resource, content, or file URI string. If your
Cursor
includes this column, then all suggestions are provided in an icon-plus-text format with the icon on the right side. This can be null or zero to indicate no icon in this row. SUGGEST_COLUMN_INTENT_ACTION
- An intent action string. If this column exists and contains a value at the
given row, the action defined here is used when forming the suggestion's
intent. If the element isn't provided, the action is taken from the
android:searchSuggestIntentAction
field in your searchable configuration. If your action is the same for all suggestions, it's more efficient to specify the action usingandroid:searchSuggestIntentAction
and omit this column. SUGGEST_COLUMN_INTENT_DATA
- A data URI string. If this column exists and contains a value at the given
row, this data is used when forming the suggestion's intent. If the element
isn't provided, the data is taken from the
android:searchSuggestIntentData
field in your searchable configuration. If neither source is provided, the intent's data field is null. If your data is the same for all suggestions, or can be described using a constant part and a specific ID, it's more efficient to specify it usingandroid:searchSuggestIntentData
and omit this column. SUGGEST_COLUMN_INTENT_DATA_ID
- A URI path string. If this column exists and contains a value at the given
row, then "/" and this value is appended to the data field in the intent.
Only use this if the data field specified by the
android:searchSuggestIntentData
attribute in the searchable configuration is already set to an appropriate base string. SUGGEST_COLUMN_INTENT_EXTRA_DATA
- Arbitrary data. If this column exists and contains a value at a given row,
this is the extra data used when forming the suggestion's intent.
If not provided, the intent's extra data field is null. This column lets
suggestions provide additional data that is included as an extra in the
intent's
EXTRA_DATA_KEY
key. SUGGEST_COLUMN_QUERY
- If this column exists and this element exists at the given row, this is
the data that is used when forming the suggestion's query, included as an
extra in the intent's
QUERY
key. It's required if the suggestion's action isACTION_SEARCH
, but optional otherwise. SUGGEST_COLUMN_SHORTCUT_ID
- Only used when providing suggestions for Quick Search Box. This column
indicates whether a search suggestion must be stored as a shortcut and
whether it must be validated. Shortcuts are usually formed when the user
taps a suggestion from Quick Search Box. If missing, the result is stored as
a shortcut and never refreshed. If set to
SUGGEST_NEVER_MAKE_SHORTCUT
, the result isn't stored as a shortcut. Otherwise, the shortcut ID is used to check back for an up-to-date suggestion usingSUGGEST_URI_PATH_SHORTCUT
. SUGGEST_COLUMN_SPINNER_WHILE_REFRESHING
- Only used when providing suggestions for Quick Search Box. This column
specifies that a spinner must be shown instead of an icon from
SUGGEST_COLUMN_ICON_2
while the shortcut of this suggestion is refreshing in Quick Search Box.
Most of these columns are discussed further in the following sections.
Declare an intent for suggestions
When the user selects a suggestion from the list that appears under the
search dialog or widget, the system sends a custom Intent
to your
searchable activity. You must define the action and data for the intent.
Declare the intent action
The most common intent action for a custom suggestion is
ACTION_VIEW
, which is appropriate when you want to open something,
like the definition for a word, a person's contact information, or a web page.
However, the intent action can be any other action and can be different for each
suggestion.
Depending on whether you want all suggestions to use the same intent action, you can define the action in two ways:
- Use the
android:searchSuggestIntentAction
attribute of your searchable configuration file to define the action for all suggestions, as shown in the following example:<?xml version="1.0" encoding="utf-8"?> <searchable xmlns:android="http://schemas.android.com/apk/res/android" android:label="@string/app_label" android:hint="@string/search_hint" android:searchSuggestAuthority="com.example.MyCustomSuggestionProvider" android:searchSuggestIntentAction="android.intent.action.VIEW" > </searchable>
- Use the
SUGGEST_COLUMN_INTENT_ACTION
column to define the action for individual suggestions. To do this, add theSUGGEST_COLUMN_INTENT_ACTION
column to your suggestions table and, for each suggestion, place in it the action to use—such as"android.intent.action.VIEW"
.
You can also combine these two techniques. For example, you can include the
android:searchSuggestIntentAction
attribute with an action to be
used with all suggestions by default, then override this action for some
suggestions by declaring a different action in the
SUGGEST_COLUMN_INTENT_ACTION
column. If you don't include a value
in the SUGGEST_COLUMN_INTENT_ACTION
column, then the intent
provided in the android:searchSuggestIntentAction
attribute is
used.
Declare intent data
When the user selects a suggestion, your searchable activity receives the
intent with the action you define—as discussed in the previous
section—but the intent must also carry data for your activity to identify
which suggestion is selected. Specifically, the data must be something unique
for each suggestion, such as the row ID for the suggestion in your SQLite table.
When the intent is received, you can retrieve the attached data with
getData()
or
getDataString()
.
You can define the data included with the intent in two ways:
- Define the data for each suggestion inside the
SUGGEST_COLUMN_INTENT_DATA
column of your suggestions table.Provide all necessary data information for each intent in the suggestions table by including the
SUGGEST_COLUMN_INTENT_DATA
column and then populating it with unique data for each row. The data from this column is attached to the intent exactly as you define it in this column. You can then retrieve it withgetData()
orgetDataString()
. - Fragment a data URI into two pieces: the portion common to all suggestions
and the portion unique to each suggestion. Place these parts into the
android:searchSuggestintentData
attribute of the searchable configuration and theSUGGEST_COLUMN_INTENT_DATA_ID
column of your suggestions table, respectively.The following example shows how to declare the piece of the URI that is common to all suggestions in the
android:searchSuggestIntentData
attribute of your searchable configuration:<?xml version="1.0" encoding="utf-8"?> <searchable xmlns:android="http://schemas.android.com/apk/res/android" android:label="@string/app_label" android:hint="@string/search_hint" android:searchSuggestAuthority="com.example.MyCustomSuggestionProvider" android:searchSuggestIntentAction="android.intent.action.VIEW" android:searchSuggestIntentData="content://com.example/datatable" > </searchable>
Include the final path for each suggestion—the unique part—in the
SUGGEST_COLUMN_INTENT_DATA_ID
column of your suggestions table. When the user selects a suggestion, the system takes the string fromandroid:searchSuggestIntentData
, appends a slash (/), and then adds the respective value from theSUGGEST_COLUMN_INTENT_DATA_ID
column to form a complete content URI. You can then retrieve theUri
withgetData()
.
Add more data
If you need to express more information with your intent, you can add another
table column, such as SUGGEST_COLUMN_INTENT_EXTRA_DATA
, which can
store additional information about the suggestion. The data saved in this column
is placed in the EXTRA_DATA_KEY
of the intent's extra bundle.
Handle the intent
After you provide custom search suggestions with custom intents, you need
your searchable activity to handle these intents when the user selects a
suggestion. This is in addition to handling the ACTION_SEARCH
intent, which your searchable activity already does. Here's an example of how
you can handle the intents during your activity's
onCreate()
callback:
Kotlin
when(intent.action) { Intent.ACTION_SEARCH -> { // Handle the normal search query case. intent.getStringExtra(SearchManager.QUERY)?.also { query -> doSearch(query) } } Intent.ACTION_VIEW -> { // Handle a suggestions click, because the suggestions all use ACTION_VIEW. showResult(intent.data) } }
Java
Intent intent = getIntent(); if (Intent.ACTION_SEARCH.equals(intent.getAction())) { // Handle the normal search query case. String query = intent.getStringExtra(SearchManager.QUERY); doSearch(query); } else if (Intent.ACTION_VIEW.equals(intent.getAction())) { // Handle a suggestions click, because the suggestions all use ACTION_VIEW. Uri data = intent.getData(); showResult(data); }
In this example, the intent action is ACTION_VIEW
and the data
carries a complete URI pointing to the suggested item, as synthesized by the
android:searchSuggestIntentData
string and
SUGGEST_COLUMN_INTENT_DATA_ID
column. The URI then passes to the
local showResult()
method that queries the content provider for the
item specified by the URI.
Rewrite the query text
By default, if the user navigates through the suggestions list using directional controls, such as with a trackball or D-pad, the query text doesn't update. However, you can temporarily rewrite the user's query text as it appears in the text box with a query that matches the suggestion in focus. This lets the user see the query being suggested, and they can select the search box and edit the query before dispatching it as a search.
You can rewrite the query text in the following ways:
- Add the
android:searchMode
attribute to your searchable configuration with the"queryRewriteFromText"
value. In this case, the content from the suggestion'sSUGGEST_COLUMN_TEXT_1
column is used to rewrite the query text. - Add the
android:searchMode
attribute to your searchable\ configuration with the"queryRewriteFromData"
value. In this case, the content from the suggestion'sSUGGEST_COLUMN_INTENT_DATA
column is used to rewrite the query text. Only use this with URIs or other data formats that are intended to be user-visible, such as HTTP URLs. Don't use internal URI schemes to rewrite the query in this way. - Provide a unique query text string in the
SUGGEST_COLUMN_QUERY
column of your suggestions table. If this column is present and contains a value for the current suggestion, it is used to rewrite the query text and override either of the previous implementations.
Expose search suggestions to Quick Search Box
Once you configure your app to provide custom search suggestions, making them
available to the globally accessible Quick Search Box is as easy as modifying
your searchable configuration to include
android:includeInGlobalSearch
with the value
"true"
.
The only scenario in which additional work is necessary is when your content
provider demands a read permission. In that case, you need to add a
<path-permission>
element for the provider to grant Quick
Search Box read access to your content provider, as shown in the following
example:
<provider android:name="MySuggestionProvider" android:authorities="com.example.MyCustomSuggestionProvider" android:readPermission="com.example.provider.READ_MY_DATA" android:writePermission="com.example.provider.WRITE_MY_DATA"> <path-permission android:pathPrefix="/search_suggest_query" android:readPermission="android.permission.GLOBAL_SEARCH" /> </provider>
In this example, the provider restricts read and write access to the content.
The <path-permission>
element amends the restriction by
granting read access to content inside the "/search_suggest_query"
path prefix when the "android.permission.GLOBAL_SEARCH"
permission
exists. This grants access to Quick Search Box so that it can query your content
provider for suggestions.
If your content provider doesn't enforce read permissions, then Quick Search Box reads it by default.
Enable suggestions on a device
By default, apps aren't enabled to provide suggestions in Quick Search Box, even if they are configured to do so. The user chooses whether to include suggestions from your app in Quick Search Box by opening Searchable items—located in Settings > Search—and enabling your app as a searchable item.
Each app that is available to Quick Search Box has an entry in the
Searchable items settings page. The entry includes the name of the app
and a short description of what content is searchable from the app and made
available for suggestions in Quick Search Box. To define the description text
for your searchable app, add the android:searchSettingsDescription
attribute to your searchable configuration, as shown in the following
example:
<?xml version="1.0" encoding="utf-8"?> <searchable xmlns:android="http://schemas.android.com/apk/res/android" android:label="@string/app_label" android:hint="@string/search_hint" android:searchSuggestAuthority="com.example.MyCustomSuggestionProvider" android:searchSuggestIntentAction="android.intent.action.VIEW" android:includeInGlobalSearch="true" android:searchSettingsDescription="@string/search_description" > </searchable>
Make the string for android:searchSettingsDescription
as concise
as possible and state the content that is searchable. For example, "Artists,
albums, and tracks" for a music app, or "Saved notes" for a notepad app.
Providing this description is important so that the user knows what kind of
suggestions are provided. Always include this attribute when
android:includeInGlobalSearch
is true.
Because the user must visit the settings menu to enable search suggestions for your app, if search is an important aspect of your app consider how to convey that to your users. For example, you might provide a note the first time a user launches the app that explains how to enable search suggestions for Quick Search Box.
Manage Quick Search Box suggestion shortcuts
Suggestions that the user selects from Quick Search Box can be automatically made into shortcuts. These are suggestions that the system copies from your content provider so it can quickly access the suggestion without needing to re-query your content provider.
By default, this is enabled for all suggestions retrieved by Quick Search
Box, but if your suggestion data changes over time, then you can request that
the shortcuts be refreshed. For example, if your suggestions refer to dynamic
data, such as a contact's presence status, then request that the suggestion
shortcuts be refreshed when shown to the user. To do this, include the
SUGGEST_COLUMN_SHORTCUT_ID
in your suggestions table. You can use
this column to configure the shortcut behavior for each suggestion in one of the
following ways:
Make Quick Search Box re-query your content provider for a fresh version of the suggestion shortcut.
Provide a value in the
SUGGEST_COLUMN_SHORTCUT_ID
column for the suggestion to be re-queried for a fresh version each time the shortcut is displayed. The shortcut quickly displays with whatever data is most recently available until the refresh query returns, at which point the suggestion is refreshed with the new information. The refresh query is sent to your content provider with a URI path ofSUGGEST_URI_PATH_SHORTCUT
—instead ofSUGGEST_URI_PATH_QUERY
.Make the
Cursor
you return contain one suggestion using the same columns as the original suggestion or be empty, indicating that the shortcut is no longer valid—in which case, the suggestion disappears and the shortcut is removed.If a suggestion refers to data that can take longer to refresh, such as a network-based refresh, you can also add the
SUGGEST_COLUMN_SPINNER_WHILE_REFRESHING
column to your suggestions table with a value of true to show a progress spinner for the right-hand icon until the refresh is complete. Any value other than true doesn't show the progress spinner.Prevent the suggestion from being copied into a shortcut at all.
Provide a value of
SUGGEST_NEVER_MAKE_SHORTCUT
in theSUGGEST_COLUMN_SHORTCUT_ID
column. In this case, the suggestion is never copied into a shortcut. This is only necessary if you absolutely don't want the previously copied suggestion to appear. If you provide a normal value for the column, then the suggestion shortcut appears only until the refresh query returns.Let the default shortcut behavior apply.
Leave the
SUGGEST_COLUMN_SHORTCUT_ID
empty for each suggestion that doesn't change and that can be saved as a shortcut.
If none of your suggestions ever change, then you don't need the
SUGGEST_COLUMN_SHORTCUT_ID
column.
About Quick Search Box suggestion ranking
Once you make your app's search suggestions available to Quick Search Box, the Quick Search Box ranking determines how the suggestions are surfaced to the user for a particular query. This might depend on how many other apps have results for that query and how often the user selects your results compared to those from other apps. There is no guarantee regarding how your suggestions are ranked or whether your app's suggestions show at all for a given query. In general, providing quality results increases the likelihood that your app's suggestions are provided in a prominent position, and apps that provide low-quality suggestions are more likely to be ranked lower or not displayed.