Build a point of interest app

This section details the different features of the library that you can make use of to implement the functionality of your point of interest (POI) app.

Declare category support in your manifest

Your app needs to declare the androidx.car.app.category.POI car app category in the intent filter of its CarAppService.

<application>
    ...
   <service
       ...
        android:name=".MyCarAppService"
        android:exported="true">
      <intent-filter>
        <action android:name="androidx.car.app.CarAppService" />
        <category android:name="androidx.car.app.category.POI"/>
      </intent-filter>
    </service>
    ...
<application>

Access the map template

Apps can access the PlaceListMapTemplate specifically designed for showing a list of points of interest alongside a map that is rendered by the host.

In order to get access to this template, your app needs to declare the androidx.car.app.MAP_TEMPLATES permission in its AndroidManifest.xml:

<uses-permission android:name="androidx.car.app.MAP_TEMPLATES"/>

Refresh PlaceListMapTemplate content

You can allow drivers to refresh content with the tap of a button while browsing lists of places built with PlaceListMapTemplate. Implement the OnContentRefreshListener interface's onContentRefreshRequested method and use PlaceListMapTemplate.Builder.setOnContentRefreshListener to set the listener on the template to enable list refresh.

The following snippet shows setting the listener on the template:

PlaceListMapTemplate.Builder()
    ...
    .setOnContentRefreshListener {
        // Execute any desired logic
        ...
        // Then call invalidate() so onGetTemplate() is called again
        invalidate()
    }
    .build()

new PlaceListMapTemplate.Builder()
        ...
        .setOnContentRefreshListener(() -> {
            // Execute any desired logic
            ...
            // Then call invalidate() so onGetTemplate() is called again
            invalidate();
        })
        .build();

The refresh button is only shown in the header of the PlaceListMapTemplate if the listener has a value.

When the driver clicks the refresh button, the onContentRefreshRequested method of your OnContentRefreshListener implementation is called. Within onContentRefreshRequested, call the Screen.invalidate method. The host subsequently calls back into your app’s Screen.onGetTemplate method to retrieve the template with the refreshed content. See Refresh the contents of a template for more information about refreshing templates. As long as the next template returned by onGetTemplate is of the same type, it is counted as a refresh and is not counted towards the template quota.

Integrate with Google Assistant using App Actions

App Actions let users launch and control Android Apps with their voice, using Google Assistant. You can integrate Assistant with point of interest apps by adding an App Actions capability. Capabilities are an expression of the relevant feature of an app and contain a Built-in intent (BII) and its fulfillment. For example, this enables users to say "Hey Google, find street parking on ExampleApp" and your app can open to the appropriate screen in your app.

Limitations

App Actions have the following limitations:

• Available only for apps that use the Car App Library in the point of interest category.
• Voice support is only for Parking or Charging Built-in intents.
• App Action fulfillment can only be done with deep links.

Integration steps

1. Add the following <meta-data> element in the <application> element of your AndroidManifest.xml file:

    <meta-data
        android:name="android.app.shortcuts"
        android:resource="@xml/shortcuts" />
   

2. To enable Assistant to link to your app's content with deep links, you need an <intent-filter> element in your AndroidManifest.xml file.

   • For Android Auto the intent-filter is the same as your mobile app.

   • For Android Automotive OS fulfillment, App Actions are triggered by CarAppService sessions. To allow a session to trigger your deeplink, you must specify an intent filter in the <activity> element of your AndroidManifest.xml file.

   <activity
     ...
     android:name="androidx.car.app.activity.CarAppActivity">
     …
     <intent-filter>
         <action android:name="android.intent.action.VIEW" />
         <category android:name="android.intent.category.DEFAULT" />
         <category android:name="android.intent.category.BROWSABLE" />
         <data 
           android:scheme="YOUR_SCHEME"
           android:host="YOUR_HOST" />
     </intent-filter>
   </activity>
   

3. Create a shortcuts.xml file in the res/xml directory of your app’s project with the appropriate capabilities:

   <?xml version="1.0" encoding="utf-8"?>
   <shortcuts xmlns:android="http://schemas.android.com/apk/res/android">
     <!-- Your Capability definitions will go here -->
   </shortcuts>
   

   See the Capability sections below for information about the Parking and Charging capabilities.

4. Update your app to handle fulfillment for a session.

   The following are samples of intent handling for Session.onCreateScreen and Session.onNewIntent

   onCreateScreen

   Kotlin

   @Override
   fun onCreateScreen(@NonNull intent: Intent): Screen {
     if (intent.getData() != null) {
         val uri: Uri = intent.getData()
         // uri = "YOUR_SCHEME://YOUR_HOST?name=Levis%20center"
         // Build your Templates with parsed uri parameters
     ...
    }
   }
   

   Java

   @Override
   public Screen onCreateScreen(@NonNull Intent intent) {
    if (intent.getData() != null) {
      Uri uri = intent.getData();
      // uri = "YOUR_SCHEME://YOUR_HOST?name=Levis%20center"
      // Build your Templates with parsed uri parameters
     …
    }
   }
   

   onNewIntent

   Kotlin

   @Override
   fun onNewIntent(@NonNull intent: Intent): Screen {
     if (intent.getData() != null) {
         val uri: Uri = intent.getData()
         // uri = "YOUR_SCHEME://YOUR_HOST?name=Levis%20center"
         // Build your Templates with parsed uri parameters
         …
     }
   }
   

   Java

   @Override
   public void onNewIntent(@NonNull Intent intent) {
    if (intent.getData() != null) {
      Uri uri = intent.getData();
      // uri = "YOUR_SCHEME://YOUR_HOST?name=Levis%20center"
      // Build your Templates with parsed uri parameters
      …
    }
   }
   

Capabilities

App Actions support the following capabilities:

• Parking
• Charging

Parking

Action ID: actions.intent.GET_PARKING_FACILITY

Description: Get parking facility. May specify a type of parking, app name, and location.

Locale support: en-US

Parameters:

• parkingFacility.disambiguatingDescription - A descriptor for the type of parking, for example "free", "valet", or "street". You can filter for the type of parking facility using this parameter.
• The following parameters can help you determine the location of the parking facility requested by the user. If none of these are present, you should return facilities closest to the user's current location.
  • parkingFacility.name - A name for the location of the facility, for example "Mountain View"
  • parkingFacility.address - An address for the location of the facility, for example "123 Easy St, Mountain View, CA"
  • parkingFacility.geo.latitude - The latitude of the facility, for example "37.3861"
  • parkingFacility.geo.longitude - The longitude of the facility, for example "-122.084"

Sample capability definition:

<?xml version="1.0" encoding="utf-8"?>
<!-- This is a sample shortcuts.xml -->
<shortcuts xmlns:android="http://schemas.android.com/apk/res/android">

  <capability android:name="actions.intent.GET_PARKING_FACILITY">
    <intent>
      <url-template
       android:value="YOUR_SCHEME://YOUR_HOST{?name,address,disambiguatingDescription,latitude,longitude}">

      <!-- Eg. name = "Googleplex" -->
      <parameter
        android:name="parkingFacility.name"
        android:key="name"/>
      <!-- Eg. address = "1600 Amphitheatre Pkwy, Mountain View, CA 94043" -->
      <parameter
        android:name="parkingFacility.address"
        android:key="address"/>
      <!-- Eg. disambiguatingDescription = "valet" -->
      <parameter
        android:name="parkingFacility.disambiguatingDescription"
        android:key="disambiguatingDescription"/>
      <!-- Eg. latitude = "37.3861" -->
      <parameter
        android:name="parkingFacility.geo.latitude"
        android:key="latitude"/>
      <!-- Eg. longitude = "-122.084" -->
      <parameter
        android:name="parkingFacility.geo.longitude"
        android:key="longitude"/>
    </intent>
  </capability>
</shortcuts>

Charging

Action ID: actions.intent.GET_CHARGING_STATION

Description: Get charging station. May specify an app name or location.

Locale support: en-US

Parameters:

• chargingStation.disambiguatingDescription - A descriptor for the type of station, for example "free", "paid". You can filter for the type of charging station using this parameter.
• The following parameters can help you determine the location of the charging station requested by the user. If none of these are present, you should return stations closest to the user's current location.
  • chargingStation.name - A name for the location of the station, for example "Mountain View"
  • chargingStation.address - An address for the location of the station, for example "123 Easy St, Mountain View, CA"
  • chargingStation.geo.latitude - The latitude of the station, for example "37.3861"
  • chargingStation.geo.longitude - The longitude of the station, for example "-122.084"

Sample capability definition:

<?xml version="1.0" encoding="utf-8"?>
<!-- This is a sample shortcuts.xml -->
<shortcuts xmlns:android="http://schemas.android.com/apk/res/android">
  <capability android:name="actions.intent.GET_CHARGING_STATION">
    <intent>
      <url-template
       android:value="YOUR_SCHEME://YOUR_HOST{?name,address,latitude,longitude,type}">

      <!-- Eg. name = "Googleplex" -->
      <parameter
        android:name="chargingStation.name"
        android:key="name"/>
      <!-- Eg. address = "1600 Amphitheatre Pkwy, Mountain View, CA 94043" -->
      <parameter
        android:name="chargingStation.address"
        android:key="address"/>
      <!-- Eg. latitude = "37.3861" -->
      <parameter
        android:name="chargingStation.geo.latitude"
        android:key="latitude"/>
      <!-- Eg. longitude = "-122.084" -->
      <parameter
        android:name="chargingStation.geo.longitude"
        android:key="longitude"/>
    </intent>
  </capability>
</shortcuts>