Merge "docs: Addressed reviews and fixes for Auto dev overview" into klp-modular-dev

<h1>Android Auto Developer Overview</h1>

<p>Android Auto extends the Android platform to car entertainment systems. When users connect

their Android handheld device to a compatible vehicle, Android Auto lets users project apps on

the vehicle’s touchscreen and interact with them using the vehicle’s controls.</p>

<p>Android Auto extends the Android platform into the car. When users connect

their Android handheld device to a compatible vehicle, Android Auto provides a car-optimized

Android experience on the vehicle's screen. Users interact with compatible apps and services

through voice actions and the vehicle's input controls.</p>

<p>The Android Auto SDK lets you easily extend your existing apps to work in the car, without

having to worry about vehicle-specific hardware differences. You can use many Android APIs and

services you are already familiar with. Android Auto provides easy to use UI templates and

supports notifications and voice actions:</p>

<dl>

<dt style="margin-bottom:10px"><strong>UI Templates</strong></dt>

<dd style="margin-bottom:20px">

Android Auto defines interaction models and UI templates for several app categories. The

Android Auto defines interaction models and UI templates for apps. The

first version of Android Auto supports media apps, such as music, podcast, live radio, and

audio news apps. Future versions will support messaging, communication, local search apps,

and more.

audio news apps.

</dd>

<dt style="margin-bottom:10px"><strong>Notifications</strong></dt>

<dd style="margin-bottom:20px">

The platform will integrate with existing Android APIs for notifications. Users will get

some notifications from Android apps on the vehicle’s screen.</dd>

car appropiate notifications from Android apps on the vehicle's screen.</dd>

<dt style="margin-bottom:10px"><strong>Voice Actions</strong></dt>

<dd style="margin-bottom:20px">

Android Auto supports voice search and voice actions for media apps. Future versions

will support additional voice actions.</dd>

Android Auto supports a set of voice actions to interact with compatible apps and services.

Apps can respond to the voice actions they're interested in, such as playing a particular song

or taking a note.</dd>

<dt style="margin-bottom:10px"><strong>Easy Development Workflow</strong></dt>

<dd style="margin-bottom:20px">

<h2 id="design">Design</h2>

<p>Digital experiences for cars should complement and augment driving, not demand the driver's

attention. Designing these experiences for cars is fundamentally different than in the case of

phones and tablets. It requires rethinking how these experiences unfold.</p>

<p>Android Auto extends users' digital ecosystem into their cars, allowing drivers to stay

connected to their virtual worlds while staying focused on the road ahead.</p>

<p>Because driving is the primary activity in the car, any digital experiences should be designed

to complement and augment that activity. They should never demand the user's attention.</p>

<h3 id="designprinciples">Design Principles</h3>

<p>Designing for cars is fundamentally different than designing for phones or tablets, and

requires rethinking how experiences unfold. Because attention is limited and not all tasks are

possible in the car, effective apps leverage the entire set of devices that drivers have,

leveraging the app experience on those devices, outside of the car, to set the stage for simple

experiences while driving.</p>

<p><strong>Glanceable</strong>. We designed Android Auto to reduce UI complexity, optimize user

interactions, and lower cognitive load. Effective apps show just enough information

and only provide features that do not require excessive menu interaction and navigation.</p>

<p>Android Auto experiences are:</p>

<p><strong>Glanceable and simple</strong>. Driving requires users' full attention. In-car software

should not. Android Auto was designed to simplify not only the UI, but to optimize interactions

and require less thinking, induce lower cognitive load, and ultimately, be safer. Effective apps

provide just enough information in the minimum amount of time the user needs to glance at it and

return their attention back to the road. Apps should also reduce the number of features to only

those that are safe and drive-appropriate.</p>

<p><strong>Predictive, yet predictable</strong>. Android Auto leverages rich, contextual awareness

to keep the driver informed about important situations. Timely help is combined with predictable

functions. Effective apps use patterns for common tasks and show timely information only when

relevant.</p>

to keep the driver informed about important situations during the drive. Rich, timely help is

combined with predictable functions. Effective apps make use of the patterns for common tasks and

show timely information only when relevant.</p>

<p><strong>Connected</strong>. By leveraging the user's personal ecosystem of apps and services,

Android Auto promotes a continuous experience from phone to car to other devices. The user's

music, destinations, and virtual ecosystem are always available to augment the drive. Experiences

that leverage personal context and other devices are naturally part of Android Auto.</p>

<p><strong>Connected</strong>. Android Auto works with apps that drivers already use in other

devices. Android Auto promotes a continuous app experience from phones and tablets to cars,

providing access to user's existing settings, subscriptions, and digital libraries. Experiences

that bring personal content and context from other devices are part of Android Auto.</p>

<p><strong>Naturally integrated</strong>. Android Auto blends the user's apps with the car,

creating a truly integrated experience that leverages what is unique about each car. By using

the screens, controls, and capabilities of the vehicle, Android Auto feels like an extension of

the car.</p>

<p><strong>Integrated</strong>. Android Auto blends your apps with the vehicle's entertainment

system, creating a truly integrated experience in every car. By using the vehicle's screen and

controls, apps feel tailored to each car.</p>

<h2 id="architecture">Architecture</h2>

<p>The Android Auto app projects your app's customized UI on the vehicle's screen. To communicate

<p>The Android Auto app shows your app's customized UI on the vehicle's screen. To communicate

with the Android Auto app, your media app implements a set of media interfaces.</p>

<div style="width:750px;margin:0 auto">

<img src="{@docRoot}auto/images/figure01.png" alt="" id="figure1" />

<img src="{@docRoot}auto/images/figure01.png" alt="" />

<p class="img-caption">

  <strong>Figure 1</strong> - Architecture of Android Auto.

</p>

<h3>Primary App Template</h3>

<p>After the user selects a media app, the display shows the primary app template. Figure

3 shows the elements of this template that you can customize:</p>

<p>You can customize the primary app template to show your own icons, app name, and

background images. Figure 4 shows an example of a customized template:</p>

<p>After the user selects a media app, the display shows the primary app template.

You can customize this template to show your own icons, app name, and

background images. Figure 3 shows an example of a customized template:</p>

<div class="cols">

<div class="auto-col-2">

</div>

</div>

<p class="img-caption">

  <strong>Figure 4.</strong> A customized template.

  <strong>Figure 3.</strong> A customized template.

</p>

<p>The primary app template supports four main actions on the action bar, four auxiliary actions

on the overflow bar, and the <em>Return</em> action. You can use standard controls and customize

the actions and icons, as shown in Figure 5.</p>

the actions and icons, as shown in Figure 4.</p>

<div class="auto-img-container-single">

  <div class="auto-img-container">

    <img class="auto-img-shot-cols" src="/auto/images/assets/do_03_more.png" />

  </div>

  <p class="img-caption" style="margin-top:0px">

    <strong>Figure 5.</strong> Custom extra actions.

    <strong>Figure 4.</strong> Custom extra actions.

  </p>

</div>

<h3 id="drawertransitions">Drawer Transitions</h3>

<p>For browse actions, the display shows the drawer transition and template:</p>

<p>After the transition from the primary app template to the drawer template, the drawer

appears on the center. The customized drawer template shows the media containers and

media files provided by the media service in your app. You can also customize drawers

with icons for list items.</p>

<p>For browse actions, the display shows the drawer transition and template, as shown in

Figure 5.</p>

<div class="cols">

<div class="auto-col-2">

</div>

</div>

<p class="img-caption">

  <strong>Figure 4.</strong> Generic and customized drawer templates.

  <strong>Figure 5.</strong> Generic and customized drawer templates.

</p>

<p>After the transition from the primary app template to the drawer template, the drawer

appears on the center. The customized drawer template shows the media containers and

media files provided by the media service in your app. You can also customize drawers

with icons for list items.</p>

<h3 id="daynighttransitions">Day and Night Transitions</h3>

<p>All the templates support different color schemes for day and night, as shown in

Figure 8. The platform provides the state (day or night) and makes adjustments automatically.</p>

<p>All the templates support different color schemes for day and night.

The platform provides the state (day or night) and makes adjustments automatically.</p>

<h3 id="customizetemplates">Customizing Templates</h3>