Android 16: Location
Kirk Scott
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16.1
16.2
16.3
16.4
16.5
Introduction
Google Services
Google Play Services
Location APIs
Making Your App Location Aware
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16.1 Introduction
• This unit belongs to the third third of the
course
• It covers a topic that might be of some
interest when developing your final project
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• Unless you planned it up front, it’s unlikely
that you could randomly add location
• However, this is a worthwhile topic to consider
since it’s part of what makes Android mobile
devices so interesting
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• The full title of the related section in the API
guide is “Location and Sensors”
• This section in the API guides consists of the
subsections listed on the following overhead
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Location and Maps
Location Strategies
Sensors Overview
Motion Sensors
Position Sensors
Environment Sensors
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• What’s shown on the following two overheads
is what you find if you go to the section on
Location and Maps
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• Location and Maps
• Note:
• This is a guide to the Android framework location
APIs in the package android.location.
• The Google Location Services API, part of Google
Play Services, provides a more powerful, highlevel framework that automates tasks such as
location provider choice and power management.
• Location Services also provides new features such
as activity detection that aren't available in the
framework API.
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• Developers who are using the framework API,
as well as developers who are just now adding
location-awareness to their apps, should
strongly consider using the Location Services
API.
• To learn more about the Location Services API,
see Google Location Services for Android.
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• So the moral of the story is that this set of
overheads will not cover any technical content
• It will just cover the overview information on
the services structure for supporting location
in Android apps
• It will conclude with the introduction to the
training section, where the reader could go for
technical content
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16.2 Google Services
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• Google Services
• Google offers a variety of services that help you build
new revenue streams, manage app distribution, track
app usage, and enhance your app with features such as
maps, sign-in, and cloud messaging.
• Although these Google services are not included in the
Android platform, they are supported by most Androidpowered devices.
• When using these services, you can distribute your app
on Google Play to all devices running Android 2.2 or
higher, and some services support even more devices.
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• Google Maps
• Include the power of Google Maps in your app
with an embeddable map view.
• You can customize the map with markers and
overlays, control the user's perspective, draw
lines and shapes, and much more.
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• Google Play In-App Billing
• Build an app with a steady revenue stream
that keeps users engaged by offering new
content or virtual goods directly in your app.
• All transactions are handled by Google Play
Store for a simple user experience.
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• Google+
• Allow users to sign in with their Google
account, customize the user experience with
Google+ info, pull people into your app with
interactive posts, and add +1 buttons so users
can recommend your content.
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• Google Wallet Instant Buy
• Provide fast and easy checkout in your app
when selling physical goods and services.
• Increase conversions by streamlining your
purchase flow and reducing the amount of
information your customers need to enter.
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• Google Cloud Platform
• Build and host the backend for your Android
app at Google-scale.
• With an infrastructure that is managed
automatically, you can focus on your app.
• Then, scale to support millions of users.
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• Google Analytics
• Measure your success and gain insights into
how users engage with your app content by
integrating Google Analytics.
• You can track in-app purchases, the number of
active users, interaction patterns, and much
more.
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• Google Cloud Messaging
• Immediately notify your users about timely
events by delivering lightweight messages
from your web server.
• There are no quotas or charges to use Google
Cloud Messaging.
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• Google Mobile Ads
• Display ads from Google Mobile Ads offer you
an alternative revenue opportunity that
leverages multiple ad networks with targeted
ads and several display formats.
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16.3 Google Play Services
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• Google Play Services
• Give your apps more features to attract users on
a wider range of devices.
• With Google Play services, your app can take
advantage of the latest, Google-powered features
such as Maps, Google+, and more, with
automatic platform updates distributed as an APK
through the Google Play store.
• This makes it faster for your users to receive
updates and easier for you to integrate the
newest that Google has to offer.
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• Google Technology
• Google Play services provides you with easy
access to Google services and is tightly
integrated with the Android OS.
• Easy-to-use client libraries are provided for
each service that let you implement the
functionality you want easier and faster.
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• Standard Authorization
• All products in Google Play services share a
common authorization API that leverages the
existing Google accounts on the device.
• You and your users have a consistent and safe
way to grant and receive OAuth2 access
tokens to Google services.
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• Automatic Updates
• Devices running Android 2.2 and newer and
that have the Google Play Store app
automatically receive updates to Google Play
services.
• Enhance your app with the most recent
version of Google Play services without
worrying about your users' Android version.
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• To start integrating Google Play services into
your app, follow the Setup guide.
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How It Works
• The Google Play services client library
• The client library contains the interfaces to the
individual Google services and allows you to
obtain authorization from users to gain access
to these services with their credentials.
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• It also contains APIs that allow you to resolve
any issues at runtime, such as a missing,
disabled, or out-of-date Google Play services
APK.
• The client library has a light footprint if you
use ProGuard as part of your build process, so
it won't have an adverse impact on your app's
file size.
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• If you want to access added features or
products, you can upgrade to a new version of
the client library as they are released.
• However, upgrading is not necessary if you
don't care about new features or bug fixes.
• We anticipate more Google services to be
continuously added, so be on the lookout for
these updates.
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• The Google Play services APK
• The Google Play services APK contains the
individual Google services and runs as a
background service in the Android OS.
• You interact with the background service
through the client library and the service
carries out the actions on your behalf.
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• An easy-to-use authorization flow is also
provided to gain access to the each Google
service, which provides consistency for both
you and your users.
• The Google Play services APK is delivered
through the Google Play Store, so updates to
the services are not dependent on carrier or
OEM system image updates.
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• In general, devices running Android 2.2
(Froyo) or later and have the Google Play
Store app installed receive updates within a
few days.
• This allows you to use the newest APIs in
Google Play services and reach most of the
devices in the Android ecosystem (devices
older than Android 2.2 or devices without the
Google Play Store app are not supported).
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• The Google Play services APK on user devices receives
regular updates for new APIs, features, and bug fixes.
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• The benefits for your app
• Google Play services gives you the freedom to
use the newest APIs for popular Google
services without worrying about device
support.
• Updates to Google Play services are
distributed automatically by the Google Play
Store and new versions of the client library are
delivered through the Android SDK Manager.
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• This makes it easy for you to focus on what's
important: your users' experience.
• To get started, set up the SDK and check out
the various products in the Google Play
services platform now!
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16.4 Location APIs
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• Location APIs
• The location APIs make it easy for you to build
location-aware applications, without needing
to focus on the details of the underlying
location technology.
• They also let you minimize power
consumption by using all of the capabilities of
the device hardware.
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• To get started, first set up the Google Play
services SDK.
• You can learn how to use the APIs in the
training class Making Your App Location
Aware, and details are available in the
Location API reference.
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Key Developer Features
• Fused location provider
• The Fused Location Provider intelligently
manages the underlying location technology
and gives you the best location according to
your needs.
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• Simple APIs:
• Lets you specify high-level needs like "high
accuracy" or "low power", instead of having to
worry about location providers.
• Immediately available:
• Gives your apps immediate access to the best,
most recent location.
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• Power-efficiency:
• Minimizes your app's use of power.
• Based on all incoming location requests and
available sensors, fused location provider
chooses the most efficient way to meet those
needs.
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• Versatility:
• Meets a wide range of needs, from foreground
uses that need highly accurate location to
background uses that need periodic location
updates with negligible power impact.
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• Geofencing APIs
• Lets your app setup geographic boundaries
around specific locations and then receive
notifications when the user enters or leaves
those areas.
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• Simple but powerful APIs:
• Allows batch addition and removal of
geofences.
• Ability to manage multiple geofences at the
same time.
• Ability to filter alerts for both entry and exit or
entry only or exit only.
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• Optimized for battery:
• Adjusts location updates based on user’s
proximity to the geofence and user’s modality
(still, walking, driving, and so on).
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• Activity recognition
• With apps becoming increasingly contextual,
understanding what the user is doing is critical
to surfacing the right content.
• The Activity recognition API makes it easy to
check the user’s current activity—still,
walking, cycling, and in-vehicle—with very
efficient use of the battery.
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• Optimized for battery:
• Uses low-power sensors to recognize the
user's current physical activity.
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• Enhances other services with context:
• Great for adding movement awareness to
location awareness.
• Apps can adjust the amount of location
awareness they provide, based on the current
user movement.
• For example, a navigation app can request
more frequent updates when the user is
driving.
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• Features for advanced applications:
• For advanced applications that want to do
their own post-processing, this API also makes
available confidence values for each of the
activities.
• It also includes two activities that indicate
unreliable measurements: unknown and tilt.
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16.5 Making Your App Location Aware
• [Note: This section is taken from the training
part of the developers’ Web site.]
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• Making Your App Location-Aware
• One of the unique features of mobile
applications is location awareness.
• Mobile users bring their devices with them
everywhere, and adding location awareness to
your app offers users a more contextual
experience.
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• The new Location Services API available in
Google Play services facilitates adding location
awareness to your app with automated
location tracking, geofencing, and activity
recognition.
• This API adds significant advantages over the
plaform's location API.
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• This class [training class, not API class] shows you
how to use Location Services in your app to get
the current location, get periodic location
updates, look up addresses, create and monitor
geofences, and detect user activities.
• The class includes sample apps and code snippets
that you can use as a starting point for adding
location awareness to your own app.
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• Note: Since this class is based on the Google
Play services client library, make sure you
install the latest version before using the
sample apps or code snippets.
• To learn how to set up the client library with
the latest version, see Setup in the Google
Play services guide.
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Lessons
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Retrieving the Current Location
Learn how to retrieve the user's current location.
Receiving Location Updates
Learn how to request and receive periodic
location updates.
• Displaying a Location Address
• Learn how to convert a location's latitude and
longitude into an address (reverse geocoding).
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• Creating and Monitoring Geofences
• Learn how to define one or more geographic
areas as locations of interest, called
geofences, and detect when the user is close
to or inside a geofence.
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• Recognizing the User's Current Activity
• Learn how to recognize the user's current
activity, such as walking, bicycling, or driving a
car, and how to use this information to modify
your app's location strategy.
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• Testing Using Mock Locations
• Learn how to test a location-aware app by
injecting mock locations into Location
Services.
• In mock mode, Location Services sends out
mock locations that you inject instead of
sensor-based locations.
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Summary and Mission
• This is where this set of overheads ends
• For the time being, none of the individual
classes will be covered
• The end of the semester is nearing
• If anyone is interested, they will have to
pursue this on their own
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The End
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