AI 147084: am: CL 147083 am: CL 147081 Add document describing AVDs and usage. (doc change only)

page.title=Android Virtual Devices

@jd:body

<div id="qv-wrapper">

<div id="qv">

  <h2>AVD quickview</h2>

  <ul>

    <li>You need to create an AVD to run any app in the Android emulator</li>

    <li>Each AVD is a completely independent virtual device, with its own

        hardware options, system image, and data storage.

    <li>You create AVD configurations to model different device environments 

        in the Android emulator.</li>

  </ul>

  <h2>In this document</h2>

  <ol>

    <li><a href="#creating">Creating an AVD</a>

      <ol>

        <li><a href="#listingtargets">Listing targets</a></li>

        <li><a href="#selectingtarget">Selecting a target</a></li>

        <li><a href="#createavd">Creating the AVD</a></li>

        <li><a href="#hardwareopts">Setting hardware emulation options</a></li>

        <li><a href="#location">Default location of the AVD files</a></li>

        <li><a href="#createavdopts">Command-line options, create avd</a></li>

      </ol>

    </li>

    <li><a href="#managing">Managing AVDs</a>

      <ol>

        <li><a href="#moving">Moving an AVD</a></li>

        <li><a href="#updating">Deleting an AVD</a></li>

        <li><a href="#deleting">Deleting an AVD</a></li>

      </ol>

    </li>

    <li><a href="#options">Command-line options</a></li>

  </ol>

  <h2>See Also</h2>

  <ol>

    <li>Android <a href="{@docRoot}guide/developing/tools/emulator.html">Emulator</a></li>

  </ol>

</div>

</div>

<p>Android Virtual Devices (AVDs) are configurations of emulator options that let

you better model an actual device.</p>

<p>Each AVD is made up of: </p>

<ul>

<li>A hardware profile.&nbsp;&nbsp;You can set options to define the hardware

features of the virtual device. For example, you can define whether the device

has a camera, whether it uses a physical QWERTY keyboard or a dialing pad, how

much memory it has, and so on. </li>

<li>A mapping to a system image.&nbsp;&nbsp;You can define what version of the

Android platform will run on the virtual device. You can choose a version of the

standard Android platform or the system image packaged with an SDK add-on.</li>

<li>Other options.&nbsp;&nbsp;You can specify the emulator skin you want to use

with the AVD, which lets you control the screen dimensions, appearance, and so

on. You can also specify the emulated SD card to use with the AVD.</li>

<li>A dedicated storage area on your development machine, in which is stored the

device's user data (installed applications, settings, and so on) and emulated SD

card.</li>

</ul>

<p>You can create as many AVDs as you need, based on the types of devices you

want to model and the Android platforms and external libraries you want to run

your application on. </p>

<p>In addition to the options in an AVD configuration, you can also

specify emulator command-line options at launch or by using the emulator

console to change behaviors or characteristics at run time. For a complete

reference of emulator options, please see the <a

href="{@docRoot}/guide/developing/tools/emulator.html">Emulator</a>

documentation. </p>

<p>To create and manage AVDs, you use the android tool provided in the Android

SDK. For more information about how to work with AVDs from inside

your development environment, see <a

href="{@docRoot}guide/developing/eclipse-adt.html">Developing in Eclipse with

ADT</a> or <a href="{@docRoot}guide/developing/other-ide.html">Developing in

Other IDEs</a>, as appropriate for your environment.</p>

<h2 id="creating">Creating an AVD</h2>

<div class="sidebox">The Android SDK does not include any preconfigured AVDs, so

you need to create an AVD before you can run any application in the emulator

(even the Hello World application). </div>

<p>To create an AVD, you use the android tool, a command-line utility

available in the <code>&lt;sdk&gt;/tools/</code> directory. Managing AVDs is one

of the two main function of the android tool (the other is creating and updating

Android projects). Open a terminal window and change to the 

<code>&lt;sdk&gt;/tools/</code> directory, if needed</p>

<p>To create each AVD, you issue the command <code>android avd create</code>,

with options that specify a name for the new AVD and the system image you want

to run on the emulator when the AVD is invoked. You can specify other options on

the command line also, such as to create an emulated SD card for the new AVD, set

the emulator skin to use, or set a custom location for the AVD's files.</p>

<p>Here's the command-line usage for creating an AVD: </p>

<pre>android -n &lt;name&gt; -t &lt;targetID&gt; [-&lt;option&gt; &lt;value&gt;] ... </pre>

<p>You can use any name you want for the AVD, but since you are likely to be

creating multiple AVDs, you should choose a name that lets you recognize the

general characteristics offered by the AVD. </p>

<p>As shown in the usage above, you must use the <code>-t</code> (or

<code>--target</code>) argument when creating a new AVD. The argument sets up a

mapping between the AVD and the system image that you want to use whenever the

AVD is invoked. You can specify any Android system image that is available in

your local SDK — it can be the system image of a standard Android platform

version or that of any SDK add-on. Later, when applications use the AVD, they'll

be running on the system that you specify in the <code>-t</code> argument.<p>

<p>To specify the system image to use, you refer to its <em>target ID</em>

— an integer — as assigned by the android tool. The target ID is not

derived from the system image name, version, or API Level, or other attribute,

so you need to have the android tool list the available system images and the

target ID of each, as described in the next section. You should do this

<em>before</em> you run the <code>android create avd</code> command.

</p>

<h3 id="listingtargets">Listing targets</h3>

<p>To generate a list of system image targets, use this command: </p>

<pre>android list targets</pre>

<p>The android tool scans the <code>&lt;sdk&gt;/platforms</code> and

<code>&lt;sdk&gt;/add-ons</code> directories looking for valid system images and

then generates the list of targets. Here's an example of the command output:

</p>

<pre>Available Android targets:

id:1

    Name: Android 1.1

    Type: platform

    API level: 2

    Skins: HVGA (default), HVGA-L, HVGA-P, QVGA-L, QVGA-P

id:2

    Name: Android 1.5

    Type: platform

    API level: 3

    Skins: HVGA (default), HVGA-L, HVGA-P, QVGA-L, QVGA-P

id:3

    Name: Google APIs

    Type: add-on

    Vendor: Google Inc.

    Description: Android + Google APIs

    Based on Android 1.5 (API level 3)

    Libraries:

    * com.google.android.maps (maps.jar)

        API for Google Maps

    Skins: HVGA (default), HVGA-L, QVGA-P, HVGA-P, QVGA-L</pre>

<h3 id="selectingtarget">Selecting a target</h3>

<p>Once you have generated the list of targets available, you can look at the

characteristics of each system image — name, API Level, external

libraries, and so on — and determine which target is appropriate for the

new AVD. </p>

<p>Keep these points in mind when you are selecting a system image target for

your AVD:</p>

<ul>

<li>The API Level of the target is important, because your application will not

be able to run on a system image whose API Level is less than that required by

your application, as specified in the <code>minSdkVersion</code> attribute of

the application's manifest file. For more information about the relationship

between system API Level and application <code>minSdkVersion</code>, see <a

href="{@docRoot}guide/publishing/versioning.html#minsdkversion">Specifying

Minimum System API Version</a>.

<li>Creating at least one AVD that uses a target whose API Level is greater than

that required by your application is strongly encouraged, because it allows you to

test the forward-compatibility of your application. Forward-compatibility

testing ensures that, when users who have downloaded your application receive a

system update, your application will continue to function normally. </li>

<li>If your application declares a <code>uses-library</code> element in its

manifest file, the application can only run on a system image in which that

external library is present. If you want your application to run on the AVD you

are creating, check the application's <code>uses-library</code> element and

select a system image target that includes that library. 

</ul>

<h3 id="createavd">Creating the AVD</h3>

<p>When you've selected the target you want to use and made a note of its ID,

use the <code>android create avd</code> command to create the AVD, supplying the

target ID as the <code>-t</code> argument. Here's an example that creates an

AVD with name "my_android1.5" and target ID "2" (the standard Android 1.5 

system image in the list above): </p>

<pre>android create avd -n my_android1.5 -t 2</pre>

<p>If the target you selected was a standard Android system image ("Type:

platform"), the android tool next asks you whether you want to create a custom

hardware profile. </p>

<pre>Android 1.5 is a basic Android platform.

Do you wish to create a custom hardware profile [no]</pre>

<p>If you want to set custom hardware emulation options for the AVD, enter

"yes" and set values as needed. If you want to use the default hardware

emulation options for the AVD, just press the return key (the default is "no").

The android tool creates the AVD with name and system image mapping you

requested, with the options you specified. 

<p class="note">If you are creating an AVD whose target is an SDK add-on,

the android tool does not allow you to set hardware emulation options. It

assumes that the provider of the add-on has set emulation options appropriately

for the device that the add-on is modeling, and so prevents you from resetting

the options. </p>

<p>For a list of options you can use in the <code>android create avd</code>

command, see the table in <a href="#options">Command-line options for AVDs</a>,

at the bottom of

this page. </p>

<h3 id="hardwareopts">Setting hardware emulation options</h3>

<p>When are creating a new AVD that uses a standard Android system image ("Type:

platform"), the android tool lets you set hardware emulation options for virtual

device. The table below lists the options available and the default values, as

well as the names of properties that store the emulated hardware options in the AVD's

configuration file (the config.ini file in the AVD's local directory). </p>

<table>

<tr>

<th>Characteristic</th>

<th>Description</th>

<th>Property</th>

</tr>

<tr>

<td>Device ram size</td>

<td>The amount of physical RAM on the device, in megabytes. Default value is "96".

<td>hw.ramSize</td>

</tr>

<tr>

<td>Touch-screen support</td>

<td>Whether there is a touch screen or not on the device. Default value is "yes".</td>

<td>hw.touchScreen

<tr>

<td>Trackball support </td>

<td>Whether there is a trackball on the device. Default value is "yes".</td>

<td>hw.trackBall</td>

</tr>

<tr>

<td>Keyboard support</td>

<td>Whether the device has a QWERTY keyboard. Default value is "yes".</td>

<td>hw.keyboard</td>

</tr>

<tr>

<td>DPad support</td>

<td>Whether the device has DPad keys. Default value is "yes".</td>

<td>hw.dPad</td>

</tr>

<tr>

<td>GSM modem support</td>

<td>Whether there is a GSM modem in the device. Default value is "yes".</td>

<td>hw.gsmModem</td>

</tr>

<tr>

<td>Camera support</td>

<td>Whether the device has a camera. Default value is "no".</td>

<td>hw.camera</td>

</tr>

<tr>

<td>Maximum horizontal camera pixels</td>

<td>Default value is "640".</td>

<td>hw.camera.maxHorizontalPixels</td>

</tr>

<tr>

<td>Maximum vertical camera pixels</td>

<td>Default value is "480".</td>

<td>hw.camera.maxVerticalPixels</td>

</tr>

<tr>

<td>GPS support</td>

<td>Whether there is a GPS in the device. Default value is "yes".</td>

<td>hw.gps</td>

</tr>

<tr>

<td>Battery support</td>

<td>Whether the device can run on a battery. Default value is "yes".</td>

<td>hw.battery</td>

</tr>

<tr>

<td>Accelerometer</td>

<td>Whether there is an accelerometer in the device. Default value is "yes".</td>

<td>hw.accelerometer</td>

</tr>

<tr>

<td>Audio recording support</td>

<td>Whether the device can record audio. Default value is "yes".</td>

<td>hw.audioInput</td>

</tr>

<tr>

<td>Audio playback support</td>

<td>Whether the device can play audio. Default value is "yes".</td>

<td>hw.audioOutput</td>

</tr>

<tr>

<td>SD Card support</td>

<td>Whether the device supports insertion/removal of virtual SD Cards. Default value is "yes".</td>

<td>hw.sdCard</td>

</tr>

<tr>

<td>Cache partition support</td>

<td>Whether we use a /cache partition on the device. Default value is "yes".</td>

<td>disk.cachePartition</td>

</tr>

<tr>

<td>Cache partition size</td>

<td>Default value is "66MB".</td>

<td>disk.cachePartition.size </td>

</tr>

</table>

<h3 id="location">Default location of the AVD files</h3>

<p>When you create an AVD, the android tool creates a dedicated directory for it

on your development computer. The directory contains the AVD configuration file,

the user data image and SD card image (if available), and any other files

associated with the device. Note that the directory does not contain a system

image — instead, the AVD configuration file contains a mapping to the

system image, which it loads when the AVD is launched. </p>

<p>The android tool also creates a &lt;AVD name&gt;.ini file for the AVD at the

root of the .android/avd directory on your computer. The file specifies the

location of the AVD directory and always remains at the root the .android 

directory.</p>

<p>By default, the android tool creates the AVD directory inside

<code>~/.android/avd/</code> (on Linux/Mac), <code>C:\Documents and

Settings\&lt;user&gt;\.android\</code> on Windows XP, and 

<code>C:\Users\&lt;user&gt;\.android\</code> on Windows Vista. 

If you want to use a custom location for the AVD directory, you 

can do so by using the <code>-p &lt;path&gt;</code> option when 

you create the AVD: </p>

<pre>android create avd -n my_android1.5 -t 2 -p path/to/my/avd</pre>

<p>If the .android directory is hosted on a network drive, we recommend using

the <code>-p</code> option to place the AVD directory in another location. 

The  AVD's .ini file remains in the .android directory on the network

drive, regardless of the location of the AVD directory. </p>

<h3 id="moving">Moving an AVD</h3>

<p>If you want to move or rename an AVD, you can do so using this command:</p>

<pre>android move avd -n &lt;name&gt; [-&lt;option&gt; &lt;value&gt;] ...</pre>

<p>The options for this command are listed in <a href="#options">Command-line

options for AVDs</a> at the bottom of this page. </p>

<h3 id="updating">Updating an AVD</h3>

<p>If, for any reason, the platform/add-on root folder has its name changed (maybe because the user has installed an update of the platform/add-on) then the AVD will not be able to load the system image that it is mapped to. In this case, the <code>android list targets</code> command will produce this output: 

<pre>The following Android Virtual Devices could not be loaded: 

Name: foo 

Path: <path>/.android/avd/foo.avd 

Error: Invalid value in image.sysdir. Run 'android update avd -n foo' </pre>

<p>To fix this error, use the <code>android update avd</code> command to recompute the path to the system images.</p>

<h3 id="deleting">Deleting an AVD</h3>

<p>You can use the android tool to delete an AVD. Here is the command usage:</p>

<pre>android delete avd -n &lt;name&gt; </pre>

<p>When you issue the command, the android tool looks for an AVD matching the 

specified name deletes the AVD's directory and files. </p>

<h2 id="options">Command-line options for AVDs</h2>

<p>The table below lists the command-line options you can use with the 

android tool. </p>

<table>

<tr>

  <th width="15%">Action</th>

  <th width="20%">Option</th>

  <th width="30%">Description</th>

  <th>Comments</th>

</tr>

<tr>

  <td><code>list&nbsp;avds</code></td>

  <td>&nbsp;</td>

  <td>List all known AVDs, with name, path, target, and skin. </td>

  <td>&nbsp;</td>

</tr>

<tr>

  <td rowspan="6"><code>create&nbsp;avd</code></td>

  <td><code>-n &lt;name&gt; or <br></code></td>

  <td>The name for the AVD.</td>

  <td>Required</td>

</tr>

<tr>

  <td><code>-t &lt;targetID&gt;</code></td>

  <td>Target ID of the system image to use with the new AVD.</td>

  <td>Required. To obtain a list of available targets, use <code>android list

      targets</code>.</td>

</tr>

<tr>

  <td><code>-c &lt;path&gt;</code> or <br>

      <code>-c &lt;size&gt;[K|M]</code></td>

  <td>The path to the SD card image to use with this AVD or the size of a new SD

      card image to create for this AVD.</td>

  <td>Examples: <code>-c path/to/sdcard</code> or <code>-c 1000M</code></td>

</tr>

<tr>

  <td><code>-f</code></td>

  <td>Force creation of the AVD</td>

  <td>By default, if the name of the AVD being created matches that of an 

      existing AVD, the android tool will not create the new AVD or overwrite 

      the existing AVD. If you specify the <code>-f</code> option, however, the 

      android tool will automatically overwrite any existing AVD that has the 

      same name as the new AVD. The files and data of the existing AVD are 

      deleted. </td>

</tr>

<tr>

  <td><code>-p &lt;path&gt;</code></td>

  <td>Path to the location at which to create the directory for this AVD's

files.</td>

  <td>&nbsp;</td>

</tr>

<tr>

  <td><code>-s &lt;name&gt;</code> or <br>

      <code>-s &lt;dimensions&gt;</code> </td>

  <td>The skin to use for this AVD, identified by name or dimensions.</td>

  <td>The android tool scans for a matching skin by name or dimension in the

<code>skins/</code> directory of the target referenced in the <code>-t

&lt;targetID&gt;</code> argument. Example: <code>-s HVGA-L</code></td>

</tr>

<tr>

  <td><code>delete&nbsp;avd</code></td>

  <td><code>-n &lt;name&gt;</code></td>

  <td>Delete the specified AVD.</td>

  <td>Required</td>

</tr>

<tr>

  <td rowspan="3"><code>move&nbsp;avd</code></td>

  <td><code>-n &lt;name&gt;</code></td>

  <td>The name of the AVD to move.</td>

  <td>Required</td>

</tr>

<tr>

  <td><code>-p &lt;path&gt;</code></td>

  <td>The path to the new location for the AVD.</td>

  <td>&nbsp;</td>

</tr>

<tr>

  <td><code>-r &lt;new-name&gt;</code></td>

  <td>Rename the AVD.</td>

  <td>&nbsp;</td>

</tr>

<tr>

  <td><code>update&nbsp;avds</code></td>

  <td>&nbsp;</td>

  <td>Recompute the paths to all system images.</td>

  <td>&nbsp;</td>

</tr>

</table>