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      1 page.title=Device Administration
      2 page.tags=devicepolicymanager,policy,security
      3 @jd:body
      4 
      5 <div id="qv-wrapper">
      6 <div id="qv">
      7     <h2>In this document</h2>
      8     <ol>
      9 <li><a href="#overview">Device Administration API Overview</a>
     10     <ol>
     11       <li><a href="#how">How does it work?</a></li>
     12       <li><a href="#policies">Policies</a></li>
     13     </ol>
     14   </li>
     15   <li><a href="#sample">Sample Application</a></li>
     16   <li><a href="#developing">Developing a Device Administration Application</a>
     17     <ol>
     18       <li><a href="#manifest">Creating the manifest</a></li>
     19       <li><a href="#code">Implementing the code</a></li>
     20     </ol>
     21   </li>
     22 
     23  </ol>
     24 
     25     <h2>Key classes</h2>
     26     <ol>
     27       <li>{@link android.app.admin.DeviceAdminReceiver}</li>
     28       <li>{@link android.app.admin.DevicePolicyManager}</li>
     29       <li>{@link android.app.admin.DeviceAdminInfo}</li>
     30     </ol>
     31 </div>
     32 </div>
     33 
     34 <p>Android 2.2 introduces support for enterprise applications by offering the
     35 Android Device Administration API. The Device Administration API provides device
     36 administration features at the system level.  These APIs allow you to create
     37 security-aware applications that are useful in enterprise settings, in which IT
     38 professionals require rich control over employee devices. For example, the
     39 built-in Android Email application has leveraged the new APIs to improve
     40 Exchange support. Through the Email application, Exchange administrators can
     41 enforce password policies &mdash;  including alphanumeric passwords or numeric
     42 PINs &mdash; across devices. Administrators can also remotely wipe (that is,
     43 restore factory defaults on) lost or stolen handsets. Exchange users can sync
     44 their email and calendar data.</p>
     45 
     46 <p>This document is intended for developers who want to develop enterprise
     47 solutions for Android-powered devices. It discusses the various features
     48 provided by the Device Administration API to provide stronger security for
     49 employee devices that are powered by Android.</p>
     50 
     51 <p class="note">
     52   <strong>Note</strong> For information on building a Work Policy
     53   Controller for Android for Work deployments, see
     54   <a href="https://developers.google.com/android/work/build-dpc"
     55   >Build a Device Policy Controller</a>.
     56 </p>
     57 
     58 <h2 id="overview">Device Administration API Overview</h2>
     59 
     60 <p>Here are examples of the types of applications that might use the Device Administration API:</p>
     61 <ul>
     62   <li>Email clients.</li>
     63   <li>Security applications that do remote wipe.</li>
     64   <li>Device management services and applications.</li>
     65 </ul>
     66 
     67 <h3 id="how">How does it work?</h3>
     68 <p>You use the Device Administration API to write device admin applications that users
     69 install on their devices. The device admin application enforces the desired
     70 policies. Here's how it works:</p> <ul>
     71   <li>A system administrator writes a device admin application that enforces
     72 remote/local device security policies. These policies could be hard-coded into
     73 the app, or the application could dynamically fetch policies from a third-party
     74 server. </li>
     75 <li>The  application is installed on users' devices. Android does
     76 not currently have an automated provisioning solution. Some of the ways a sysadmin might
     77 distribute the application to users are as follows:
     78 <ul>
     79 <li>Google Play.</li>
     80 <li>Enabling installation from another store.</li>
     81 <li>Distributing the application through other means, such as email or websites.</li>
     82 
     83 </ul>
     84 
     85 
     86 </li>
     87   <li>The system prompts the user to enable the device admin application. How
     88 and when this happens depends on how the application is implemented.</li>
     89 <li>Once  users enable the device admin application, they are subject to
     90 its policies. Complying with those policies typically confers benefits, such as
     91 access to sensitive systems and data.</li>
     92 </ul>
     93 <p>If users do not enable the device admin app, it remains on the device, but in an inactive state. Users will not be subject to its policies, and they will conversely not get any of the application's benefits&mdash;for example, they may not be able to sync data.</p>
     94 <p>If a user fails to comply with the policies (for example, if a user sets a
     95 password that violates the guidelines), it is up to the application to decide
     96 how to handle this. However, typically this will result in the user not being
     97 able to sync data.</p>
     98 <p>If a device attempts to connect to a server that requires policies not
     99 supported in the Device Administration API, the connection will not
    100 be allowed. The Device Administration API does not currently allow partial
    101 provisioning. In other words, if a device (for example, a legacy device) does
    102 not support all of the stated policies, there is no way to allow the
    103 device to connect.</p>
    104 <p>If a device contains multiple enabled admin applications, the strictest policy is
    105 enforced. There is no way to target a particular admin
    106 application.</p>
    107 <p>To uninstall an existing device admin application, users need to
    108 first unregister the application as an administrator. </p>
    109 
    110 
    111 <h3 id="policies">Policies</h3>
    112 
    113 <p>In an enterprise setting, it's often the case that employee devices must
    114 adhere to a strict set of policies that govern the use of the device. The
    115 Device Administration API supports the  policies listed in Table 1.
    116 Note that the Device Administration API currently only supports passwords for screen
    117 lock:</p>
    118 <p class="table-caption"><strong>Table 1.</strong> Policies supported by the Device Administration API.</p>
    119 <table border="1">
    120   <tr>
    121     <th>Policy</th>
    122     <th>Description</th>
    123   </tr>
    124   <tr>
    125     <td>Password enabled</td>
    126     <td>Requires that devices ask for PIN or passwords.</td>
    127   </tr>
    128   <tr>
    129     <td>Minimum password length</td>
    130     <td>Set the required number of characters for the password. For example, you
    131 can require PIN or passwords to have at least six characters. </td> </tr>
    132   <tr>
    133     <td>Alphanumeric password required</td>
    134     <td>Requires that passwords have a
    135 combination of letters and numbers. They may include symbolic characters.
    136     </td>
    137   </tr>
    138 
    139   <tr>
    140     <td>Complex password required</td>
    141     <td>Requires that passwords must contain at least a letter, a numerical digit, and a special symbol. Introduced in Android 3.0.
    142     </td>
    143   </tr>
    144 
    145 <tr>
    146   <td>Minimum letters required in password</td> <td>The minimum number of
    147 letters required in the password for all admins or a particular one. Introduced in Android 3.0.</td>
    148 </tr>
    149 
    150 
    151   <tr>
    152   <td>Minimum lowercase letters required in password</td>
    153   <td>The minimum number of lowercase
    154 letters required in the password for all admins or a particular one. Introduced in Android 3.0.</td>
    155 </tr>
    156 
    157   <tr>
    158   <td>Minimum non-letter characters required in password</td>
    159   <td>The minimum number of
    160 non-letter characters required in the password for all admins or a particular one. Introduced in Android 3.0.</td>
    161 </tr>
    162 
    163 <tr>
    164   <td>Minimum numerical digits required in password</td>
    165   <td>The minimum number of numerical digits required in the password for all admins or a particular one. Introduced in Android 3.0.</td>
    166 </tr>
    167 
    168 <tr>
    169   <td>Minimum symbols required in password</td>
    170   <td>The minimum number of symbols required in the password for all admins or a particular one. Introduced in Android 3.0.</td>
    171 </tr>
    172 
    173 <tr>
    174   <td>Minimum uppercase letters required in password</td>
    175   <td>The minimum number of uppercase letters required in the password for all admins or a particular one. Introduced in Android 3.0.</td>
    176 </tr>
    177 
    178 <tr>
    179   <td>Password expiration timeout</td>
    180   <td>When the password will expire, expressed as a delta in milliseconds from when a device admin sets the expiration timeout. Introduced in Android 3.0.</td>
    181 </tr>
    182 
    183 <tr>
    184   <td>Password history restriction</td>
    185   <td>This policy prevents users from reusing the last <em>n</em> unique passwords.
    186  This policy is typically used in conjunction with
    187 {@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()}, which forces
    188 users to update their passwords after a specified amount of time has elapsed.
    189 Introduced in Android 3.0.</td>
    190 </tr>
    191 
    192   <tr>
    193     <td>Maximum failed password attempts </td>
    194     <td>Specifies how many times a user can enter the wrong password before the
    195 device wipes its data.  The Device Administration API also allows administrators to
    196 remotely reset the device to  factory defaults. This secures data in case the
    197 device is lost or stolen.</td>
    198   </tr>
    199   <tr>
    200     <td>Maximum inactivity time lock</td>
    201     <td>Sets the length of time since the user last touched the screen or
    202 pressed a button before the device locks the screen. When this happens, users
    203 need to enter their PIN or passwords again before they can use their devices and
    204 access data.  The value can be between 1 and 60 minutes.</td> </tr>
    205 
    206 <tr>
    207 <td>Require storage encryption</td>
    208 <td>Specifies that the storage area should be encrypted, if the device supports it.
    209 Introduced in Android 3.0.</td> </tr>
    210 
    211 <tr>
    212   <td>Disable camera</td>
    213 
    214   <td>Specifies that the camera should be disabled. Note that this doesn't have
    215 to be a permanent disabling. The camera can be enabled/disabled dynamically
    216 based on context, time, and so on. Introduced in Android 4.0.</td>
    217 
    218 </tr>
    219 
    220 
    221 </table>
    222 
    223 <h4>Other features</h4>
    224 
    225 <p>In addition to supporting the policies listed in the above table, the Device
    226 Administration API lets you do the following:</p> <ul>
    227   <li>Prompt user to set a new password.</li>
    228   <li>Lock device immediately.</li>
    229   <li>Wipe the device's data (that is, restore the device to its factory defaults).</li>
    230 </ul>
    231 
    232 
    233 <h2 id="sample">Sample Application</h2>
    234 
    235 <p>The examples used in this document are based on the Device Administration API
    236 sample, which is included in the SDK samples (available through the
    237 Android SDK Manager) and located on your system as
    238 <code>&lt;sdk_root&gt;/ApiDemos/app/src/main/java/com/example/android/apis/app/DeviceAdminSample.java</code>.</p>
    239 
    240 <p>The sample application offers a demo of device admin features. It presents users
    241 with a user interface that lets them enable the device admin application. Once
    242 they've enabled the application, they can use the buttons in the user interface
    243 to do the following:</p>
    244 <ul>
    245   <li>Set password quality.</li>
    246   <li>Specify requirements for the user's password, such as minimum length, the minimum number of
    247   numeric characters it must contain, and so on.</li>
    248   <li>Set the password. If the password does not conform to the specified
    249 policies, the system  returns an error.</li>
    250   <li>Set how many failed password attempts can occur before the device is wiped
    251 (that is, restored to factory settings).</li>
    252 <li>Set how long from now the password will expire.</li>
    253 <li>Set the password history length (<em>length</em> refers to number of old passwords stored in the history).
    254 This prevents users from reusing
    255 one of the last <em>n</em> passwords they previously used.</li>
    256 <li>Specify that the storage area should be encrypted, if the device supports it.</li>
    257   <li>Set the maximum amount of inactive time that can elapse before the device
    258 locks.</li>
    259   <li>Make the device lock immediately.</li>
    260   <li>Wipe the device's data (that is, restore factory settings).</li>
    261   <li>Disable the camera.</li>
    262 
    263 </ul>
    264 
    265 
    266 
    267 <img src="{@docRoot}images/admin/device-admin-app.png"/>
    268 
    269 <p class="img-caption"><strong>Figure 1.</strong> Screenshot of the Sample Application</p>
    270 
    271 
    272 
    273 <h2 id="developing">Developing a Device Administration Application</h2>
    274 
    275 <p>System administrators can use the Device Administration API to write an application
    276 that enforces remote/local device security policy enforcement. This section
    277 summarizes the steps involved in creating a device administration
    278 application.</p>
    279 
    280 <h3 id="manifest">Creating the manifest</h3>
    281 
    282 <p>To use the Device Administration API, the application's
    283 manifest must include the following:</p>
    284 <ul>
    285   <li>A subclass of {@link android.app.admin.DeviceAdminReceiver} that includes the following:
    286     <ul>
    287       <li>The {@link android.Manifest.permission#BIND_DEVICE_ADMIN} permission.</li>
    288       <li>The ability to  respond to the {@link android.app.admin.DeviceAdminReceiver#ACTION_DEVICE_ADMIN_ENABLED}
    289 intent, expressed in the manifest as an intent filter.</li>
    290     </ul>
    291   </li>
    292   <li>A declaration of security policies used in metadata.</li>
    293 </ul>
    294 <p>Here is an excerpt from the Device Administration sample manifest:</p>
    295 <pre>&lt;activity android:name=&quot;.app.DeviceAdminSample&quot;
    296             android:label=&quot;&#64;string/activity_sample_device_admin&quot;&gt;
    297     &lt;intent-filter&gt;
    298         &lt;action android:name=&quot;android.intent.action.MAIN&quot; /&gt;
    299         &lt;category android:name=&quot;android.intent.category.SAMPLE_CODE&quot; /&gt;
    300     &lt;/intent-filter&gt;
    301 &lt;/activity&gt;
    302 &lt;receiver android:name=&quot;.app.DeviceAdminSample$DeviceAdminSampleReceiver&quot;
    303         android:label=&quot;&#64;string/sample_device_admin&quot;
    304         android:description=&quot;&#64;string/sample_device_admin_description&quot;
    305         android:permission=&quot;android.permission.BIND_DEVICE_ADMIN&quot;&gt;
    306     &lt;meta-data android:name=&quot;android.app.device_admin&quot;
    307             android:resource=&quot;&#64;xml/device_admin_sample&quot; /&gt;
    308     &lt;intent-filter&gt;
    309         &lt;action android:name=&quot;android.app.action.DEVICE_ADMIN_ENABLED&quot; /&gt;
    310     &lt;/intent-filter&gt;
    311 &lt;/receiver&gt;</pre>
    312 
    313  <p>Note that:</p>
    314 <ul>
    315 <li>The following attributes refer to string resources that for the sample application reside in
    316 <code>ApiDemos/res/values/strings.xml</code>. For more information about resources, see
    317 <a
    318 href="{@docRoot}guide/topics/resources/index.html">Application Resources</a>.
    319 <ul>
    320 <li><code>android:label=&quot;&#64;string/activity_sample_device_admin&quot;</code> refers to the
    321 user-readable label for the activity.</li>
    322 
    323 <li><code>android:label=&quot;&#64;string/sample_device_admin&quot;</code> refers to the
    324 user-readable label for the permission.</li>
    325 
    326 <li><code>android:description=&quot;&#64;string/sample_device_admin_description&quot;</code> refers to
    327 the user-readable description of the permission. A descripton is typically longer and more
    328 informative than
    329 a label.</li>
    330 </ul>
    331 
    332 
    333 <li><code>android:permission=&quot;android.permission.BIND_DEVICE_ADMIN&quot;
    334 </code> is a permission that a {@link android.app.admin.DeviceAdminReceiver} subclass must
    335 have, to ensure that only the system can interact with the receiver (no application can be granted this permission). This
    336 prevents other applications from abusing your device admin app.</li>
    337 <li><code>android.app.action.DEVICE_ADMIN_ENABLED</code> is the primary
    338 action that a {@link android.app.admin.DeviceAdminReceiver} subclass must handle to be
    339 allowed to manage a device. This is set to the receiver when the user enables
    340 the device admin app. Your code typically handles this in
    341 {@link android.app.admin.DeviceAdminReceiver#onEnabled onEnabled()}. To be supported, the receiver must also
    342 require the {@link android.Manifest.permission#BIND_DEVICE_ADMIN} permission so that other applications
    343 cannot abuse it.  </li>
    344 <li>When a user enables the device admin application, that gives the receiver
    345 permission to perform actions in response to the broadcast of particular system
    346 events. When suitable event arises, the application can impose a policy. For
    347 example, if the user attempts to set a new password that doesn't meet the policy
    348 requirements, the application can prompt the user to pick a different password
    349 that does meet the requirements.</li>
    350 
    351   <li><code>android:resource=&quot;&#64;xml/device_admin_sample&quot;</code>
    352 declares the security policies used in metadata. The metadata provides additional
    353 information specific to the device administrator, as parsed by the {@link
    354 android.app.admin.DeviceAdminInfo} class. Here are the contents of
    355 <code>device_admin_sample.xml</code>:</li>
    356 </ul>
    357 <pre>&lt;device-admin xmlns:android=&quot;http://schemas.android.com/apk/res/android">;
    358   &lt;uses-policies&gt;
    359     &lt;limit-password /&gt;
    360     &lt;watch-login /&gt;
    361     &lt;reset-password /&gt;
    362     &lt;force-lock /&gt;
    363     &lt;wipe-data /&gt;
    364     &lt;expire-password /&gt;
    365     &lt;encrypted-storage /&gt;
    366     &lt;disable-camera /&gt;
    367   &lt;/uses-policies&gt;
    368 &lt;/device-admin&gt;
    369 </pre>
    370 <p> In designing your device administration application, you don't need to
    371 include all of the policies, just the ones that are relevant for your app.
    372 </p>
    373 For more discussion of the manifest file, see the <a
    374 href="{@docRoot}guide/topics/manifest/manifest-intro.html">Android Developers Guide</a>.
    375 
    376 
    377 
    378 <h3 id="code">Implementing the code</h3>
    379 
    380 <p>The Device Administration API includes the following classes:</p>
    381 <dl>
    382   <dt>{@link android.app.admin.DeviceAdminReceiver}</dt>
    383      <dd>Base class for implementing a device administration component. This class provides
    384 a convenience for interpreting the raw intent actions   that are sent by the
    385 system. Your Device Administration application must include a
    386 {@link android.app.admin.DeviceAdminReceiver} subclass.</dd>
    387   <dt>{@link android.app.admin.DevicePolicyManager}</dt>
    388 <dd>A class for managing policies enforced on a device. Most clients of
    389 this class must have published a {@link android.app.admin.DeviceAdminReceiver} that the user
    390 has currently enabled. The {@link android.app.admin.DevicePolicyManager} manages policies for
    391 one or more {@link android.app.admin.DeviceAdminReceiver} instances</dd>
    392   <dt>{@link android.app.admin.DeviceAdminInfo}</dt>
    393 <dd>This class is used to specify metadata
    394 for a device administrator component.</dd>
    395 </dl>
    396 <p>These classes provide the foundation for a fully functional device administration application.
    397 The rest of this section describes how you use the {@link
    398 android.app.admin.DeviceAdminReceiver} and
    399 {@link android.app.admin.DevicePolicyManager} APIs to write a device admin application.</p>
    400 
    401 <h4 id="receiver">Subclassing DeviceAdminReceiver</h4>
    402 <p>To create a device admin application, you must subclass
    403 {@link android.app.admin.DeviceAdminReceiver}. The {@link android.app.admin.DeviceAdminReceiver} class
    404 consists of a series of callbacks that are triggered when particular events
    405 occur.</p>
    406 <p>In its {@link android.app.admin.DeviceAdminReceiver} subclass, the sample application
    407 simply displays a {@link android.widget.Toast} notification in response to particular
    408 events. For example:</p>
    409 <pre>public class DeviceAdminSample extends DeviceAdminReceiver {
    410 
    411     void showToast(Context context, String msg) {
    412         String status = context.getString(R.string.admin_receiver_status, msg);
    413         Toast.makeText(context, status, Toast.LENGTH_SHORT).show();
    414     }
    415 
    416     &#64;Override
    417     public void onEnabled(Context context, Intent intent) {
    418         showToast(context, context.getString(R.string.admin_receiver_status_enabled));
    419     }
    420 
    421     &#64;Override
    422     public CharSequence onDisableRequested(Context context, Intent intent) {
    423         return context.getString(R.string.admin_receiver_status_disable_warning);
    424     }
    425 
    426     &#64;Override
    427     public void onDisabled(Context context, Intent intent) {
    428         showToast(context, context.getString(R.string.admin_receiver_status_disabled));
    429     }
    430 
    431     &#64;Override
    432     public void onPasswordChanged(Context context, Intent intent) {
    433         showToast(context, context.getString(R.string.admin_receiver_status_pw_changed));
    434     }
    435 ...
    436 }</pre>
    437 
    438 
    439 <h4 id="enabling">Enabling the application</h4>
    440 <p>One of the major events a device admin application has to handle is the user
    441 enabling the application. The user must explicitly enable the application for
    442 the policies to be enforced. If the user chooses not to enable the application
    443 it will still be present on the device, but its policies will not be enforced, and the user will not
    444 get any of the application's benefits.</p>
    445 <p>The process of enabling the application begins when the user performs an
    446 action that triggers the {@link android.app.admin.DevicePolicyManager#ACTION_ADD_DEVICE_ADMIN}
    447 intent. In the
    448 sample application, this happens when the user clicks the <strong>Enable
    449 Admin</strong> checkbox. </p>
    450 <p>When the user clicks the <strong>Enable Admin</strong> checkbox, the display
    451 changes to prompt the user to activate the device admin application, as shown in figure
    452 2.</p>
    453 
    454 <img src="{@docRoot}images/admin/device-admin-activate-prompt.png"/>
    455 <p class="img-caption"><strong>Figure 2.</strong> Sample Application: Activating the Application</p>
    456 
    457 <p>Below  is the code that gets executed when the user clicks the <strong>Enable Admin</strong> checkbox. This has the effect of triggering the
    458 {@link android.preference.Preference.OnPreferenceChangeListener#onPreferenceChange(android.preference.Preference, java.lang.Object) onPreferenceChange()}
    459 callback. This callback is invoked when the value of this  {@link android.preference.Preference} has been changed by the user and is about to be set and/or persisted. If the user is enabling the application, the display
    460 changes to prompt the user to activate the device admin application, as shown in figure
    461 2. Otherwise, the device admin application is disabled. </p>
    462 
    463 <pre>&#64;Override
    464         public boolean onPreferenceChange(Preference preference, Object newValue) {
    465             if (super.onPreferenceChange(preference, newValue)) {
    466                 return true;
    467             }
    468             boolean value = (Boolean) newValue;
    469             if (preference == mEnableCheckbox) {
    470                 if (value != mAdminActive) {
    471                     if (value) {
    472                         // Launch the activity to have the user enable our admin.
    473                         Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
    474                         intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, mDeviceAdminSample);
    475                         intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION,
    476                                 mActivity.getString(R.string.add_admin_extra_app_text));
    477                         startActivityForResult(intent, REQUEST_CODE_ENABLE_ADMIN);
    478                         // return false - don't update checkbox until we're really active
    479                         return false;
    480                     } else {
    481                         mDPM.removeActiveAdmin(mDeviceAdminSample);
    482                         enableDeviceCapabilitiesArea(false);
    483                         mAdminActive = false;
    484                     }
    485                 }
    486             } else if (preference == mDisableCameraCheckbox) {
    487                 mDPM.setCameraDisabled(mDeviceAdminSample, value);
    488                 ...
    489             }
    490             return true;
    491         }</pre>
    492 
    493 
    494 <p>The line
    495 <code>intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN,
    496 mDeviceAdminSample)</code> states that <code>mDeviceAdminSample</code> (which is
    497 a {@link android.app.admin.DeviceAdminReceiver} component) is the target policy.
    498 This line invokes the user interface shown in figure 2, which guides users through
    499 adding the device administrator to the system (or allows them to reject it).</p>
    500 
    501 <p>When the application needs to perform an operation that is contingent on the
    502 device admin application being enabled, it confirms that the application is
    503 active. To do this it uses the {@link android.app.admin.DevicePolicyManager} method
    504 {@link android.app.admin.DevicePolicyManager#isAdminActive(android.content.ComponentName) isAdminActive()}. Notice that the {@link android.app.admin.DevicePolicyManager}
    505 method {@link android.app.admin.DevicePolicyManager#isAdminActive(android.content.ComponentName) isAdminActive()} takes a {@link android.app.admin.DeviceAdminReceiver}
    506 component as its argument:</p>
    507 
    508 <pre>
    509 DevicePolicyManager mDPM;
    510 ...
    511 private boolean isActiveAdmin() {
    512     return mDPM.isAdminActive(mDeviceAdminSample);
    513 }
    514 </pre>
    515 
    516 
    517 
    518 <h3 id="admin_ops">Managing policies</h3>
    519 <p>{@link android.app.admin.DevicePolicyManager} is a public class for managing policies
    520 enforced on a device. {@link android.app.admin.DevicePolicyManager} manages policies for one
    521 or more {@link android.app.admin.DeviceAdminReceiver} instances. </p>
    522 <p>You get a handle to the {@link android.app.admin.DevicePolicyManager} as follows: </p>
    523 <pre>
    524 DevicePolicyManager mDPM =
    525     (DevicePolicyManager)getSystemService(Context.DEVICE_POLICY_SERVICE);
    526 </pre>
    527 <p>This section describes how to use {@link android.app.admin.DevicePolicyManager} to perform
    528  administrative tasks:</p>
    529 <ul>
    530   <li><a href="#pwd">Set password policies</a></li>
    531   <li><a href="#lock">Set  device lock</a></li>
    532   <li><a href="#wipe">Perform data wipe</a></li>
    533 </ul>
    534 
    535 <h4 id="pwd">Set password policies</h4>
    536 <p>{@link android.app.admin.DevicePolicyManager} includes APIs for setting and enforcing the
    537 device password policy. In the Device Administration API, the password only applies to
    538 screen lock. This section describes common password-related tasks.</p>
    539 
    540 <h5>Set a password for the device</h5>
    541 <p>This code displays a user interface prompting the user to set a password:</p>
    542 <pre>Intent intent = new Intent(DevicePolicyManager.ACTION_SET_NEW_PASSWORD);
    543 startActivity(intent);
    544 </pre>
    545 
    546 <h5>Set the password quality</h5>
    547 <p>The password quality can be one of the following {@link android.app.admin.DevicePolicyManager} constants: </p>
    548 <dl>
    549   <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_ALPHABETIC}</dt><dd>The user must enter a
    550 password containing at least alphabetic (or other symbol) characters.</dd>
    551   <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_ALPHANUMERIC}</dt><dd>The user must enter a
    552 password containing at least <em>both</em> numeric <em>and</em> alphabetic (or
    553 other symbol) characters.</dd>
    554   <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_NUMERIC}</dt><dd>The user must enter a   password
    555 containing at least numeric characters.</dd>
    556 <dt>{@link
    557 android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_COMPLEX}</dt><dd>The user
    558 must have entered a password containing at least a letter, a numerical digit and
    559 a special symbol.</dd>
    560 <dt>{@link
    561 android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_SOMETHING}</dt><dd>The
    562 policy requires some kind
    563 of password, but doesn't care what it is.</dd>
    564   <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_UNSPECIFIED}</dt><dd>
    565   The policy has no requirements   for the password. </dd>
    566 </dl>
    567 <p>For example, this is how you would set the password policy to require an alphanumeric password:</p>
    568 <pre>
    569 DevicePolicyManager mDPM;
    570 ComponentName mDeviceAdminSample;
    571 ...
    572 mDPM.setPasswordQuality(mDeviceAdminSample, DevicePolicyManager.PASSWORD_QUALITY_ALPHANUMERIC);
    573 </pre>
    574 
    575 <h5>Set password content requirements</h5>
    576 
    577 <p>Beginning with Android 3.0, the {@link android.app.admin.DevicePolicyManager} class
    578 includes methods that let you fine-tune the contents of the password. For
    579 example, you could set a policy that states that passwords must contain at least
    580 <em>n</em> uppercase letters. Here are the methods for fine-tuning a password's
    581 contents:</p>
    582 <ul>
    583 
    584 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumLetters(android.content.ComponentName,int) setPasswordMinimumLetters()}</li>
    585 
    586 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumLowerCase(android.content.ComponentName,int) setPasswordMinimumLowerCase()}</li>
    587 
    588 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumUpperCase(android.content.ComponentName,int) setPasswordMinimumUpperCase()}</li>
    589 
    590 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumNonLetter(android.content.ComponentName,int) setPasswordMinimumNonLetter()}</li>
    591 
    592 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumNumeric(android.content.ComponentName,int) setPasswordMinimumNumeric()}</li>
    593 
    594 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumSymbols(android.content.ComponentName,int) setPasswordMinimumSymbols()}</li>
    595 </ul>
    596 <p>For example, this snippet states that the password must have at least 2 uppercase letters:</p>
    597 <pre>
    598 DevicePolicyManager mDPM;
    599 ComponentName mDeviceAdminSample;
    600 int pwMinUppercase = 2;
    601 ...
    602 mDPM.setPasswordMinimumUpperCase(mDeviceAdminSample, pwMinUppercase);</pre>
    603 
    604 
    605 <h5>Set the minimum password length</h5>
    606 <p>You can specify that a password must be at least the specified minimum
    607 length. For example:</p>
    608 <pre>DevicePolicyManager mDPM;
    609 ComponentName mDeviceAdminSample;
    610 int pwLength;
    611 ...
    612 mDPM.setPasswordMinimumLength(mDeviceAdminSample, pwLength);
    613 </pre>
    614 
    615 <h5>Set maximum failed password attempts</h5>
    616 <p>You can set the maximum number of allowed failed password attempts before the
    617 device is wiped (that is, reset to factory settings). For example:</p>
    618 <pre>DevicePolicyManager mDPM;
    619 ComponentName mDeviceAdminSample;
    620 int maxFailedPw;
    621  ...
    622 mDPM.setMaximumFailedPasswordsForWipe(mDeviceAdminSample, maxFailedPw);</pre>
    623 
    624 <h5 id="expiration">Set password expiration timeout</h5>
    625 <p>Beginning with Android 3.0, you can use the
    626 {@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()}
    627 method to set when a password will expire, expressed as a delta in milliseconds from when a device admin sets the expiration timeout. For example:</p>
    628 
    629 <pre>DevicePolicyManager mDPM;
    630 ComponentName mDeviceAdminSample;
    631 long pwExpiration;
    632 ...
    633 mDPM.setPasswordExpirationTimeout(mDeviceAdminSample, pwExpiration);
    634 </pre>
    635 
    636 <h5 id="history">Restrict password based on history</h5>
    637 
    638 <p>Beginning with Android 3.0, you can use the
    639 {@link android.app.admin.DevicePolicyManager#setPasswordHistoryLength(android.content.ComponentName,int) setPasswordHistoryLength()}
    640 method to limit users'
    641 ability to reuse old passwords. This method takes a <em>length</em>
    642 parameter, which specifies how many old
    643 passwords are stored. When this policy is active, users cannot enter a new
    644 password that matches the last <em>n</em> passwords. This prevents
    645 users from using the same password over and over. This policy is typically used
    646 in conjunction with
    647 {@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()},
    648 which forces users
    649 to update their passwords after a specified amount of time has elapsed. </p>
    650 
    651 <p>For example, this snippet prohibits users from reusing any of their last 5 passwords:</p>
    652 
    653 <pre>DevicePolicyManager mDPM;
    654 ComponentName mDeviceAdminSample;
    655 int pwHistoryLength = 5;
    656 ...
    657 mDPM.setPasswordHistoryLength(mDeviceAdminSample, pwHistoryLength);
    658 </pre>
    659 
    660 <h4 id="lock">Set device lock</h4>
    661 <p>You can set the maximum period of user inactivity that can occur before the
    662 device locks. For example:</p>
    663 <pre>
    664 DevicePolicyManager mDPM;
    665 ComponentName mDeviceAdminSample;
    666 ...
    667 long timeMs = 1000L*Long.parseLong(mTimeout.getText().toString());
    668 mDPM.setMaximumTimeToLock(mDeviceAdminSample, timeMs);
    669 </pre>
    670 <p>You can also programmatically tell the device to lock immediately:</p>
    671 <pre>
    672 DevicePolicyManager mDPM;
    673 mDPM.lockNow();
    674 </pre>
    675 
    676 
    677 
    678 <h4 id="wipe">Perform data wipe</h4>
    679 
    680 <p>You can use the {@link android.app.admin.DevicePolicyManager} method
    681 {@link android.app.admin.DevicePolicyManager#wipeData wipeData()} to reset the device to factory settings. This is useful
    682 if the device is lost or stolen. Often the decision to wipe the device is the
    683 result of certain conditions being met. For example, you can use
    684 {@link android.app.admin.DevicePolicyManager#setMaximumFailedPasswordsForWipe setMaximumFailedPasswordsForWipe()} to state that a device should be
    685 wiped after a specific number of failed password attempts.</p>
    686 <p>You wipe data as follows:</p>
    687 <pre>
    688 DevicePolicyManager mDPM;
    689 mDPM.wipeData(0);</pre>
    690 <p>The {@link android.app.admin.DevicePolicyManager#wipeData wipeData()} method takes as its
    691   parameter a bit mask of additional options. Currently the value must be 0. </p>
    692 
    693 <h4>Disable camera</h4>
    694 <p>Beginning with Android 4.0, you can disable the camera. Note that this doesn't have to be a permanent disabling. The camera can be enabled/disabled dynamically based on context, time, and so on. </p>
    695 <p>You control whether the camera is disabled by using the
    696 {@link android.app.admin.DevicePolicyManager#setCameraDisabled(android.content.ComponentName, boolean) setCameraDisabled()} method. For example, this snippet sets the camera to be enabled or disabled based on a checkbox setting:</p>
    697 
    698 <pre>private CheckBoxPreference mDisableCameraCheckbox;
    699 DevicePolicyManager mDPM;
    700 ComponentName mDeviceAdminSample;
    701 ...
    702 mDPM.setCameraDisabled(mDeviceAdminSample, mDisableCameraCheckbox.isChecked());<br />
    703 </pre>
    704 
    705 
    706 <h4 id="storage">Storage encryption</h4>
    707 <p>Beginning with Android 3.0, you can use the
    708 {@link android.app.admin.DevicePolicyManager#setStorageEncryption(android.content.ComponentName,boolean) setStorageEncryption()}
    709 method to set a policy requiring encryption of the storage area, where supported.</p>
    710 
    711 <p>For example:</p>
    712 
    713 <pre>
    714 DevicePolicyManager mDPM;
    715 ComponentName mDeviceAdminSample;
    716 ...
    717 mDPM.setStorageEncryption(mDeviceAdminSample, true);
    718 </pre>
    719 <p>
    720 See the Device Administration API sample for a complete example of how to enable storage encryption.
    721 </p>
    722