1page.title=Device Administration 2page.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 <h2>Related samples</h2> 32 <ol> 33 <li><a 34href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/DeviceAdminSample.html"> 35DeviceAdminSample</a></li> 36</ol> 37</div> 38</div> 39 40<p>Android 2.2 introduces support for enterprise applications by offering the 41Android Device Administration API. The Device Administration API provides device 42administration features at the system level. These APIs allow you to create 43security-aware applications that are useful in enterprise settings, in which IT 44professionals require rich control over employee devices. For example, the 45built-in Android Email application has leveraged the new APIs to improve 46Exchange support. Through the Email application, Exchange administrators can 47enforce password policies — including alphanumeric passwords or numeric 48PINs — across devices. Administrators can also remotely wipe (that is, 49restore factory defaults on) lost or stolen handsets. Exchange users can sync 50their email and calendar data.</p> 51 52<p>This document is intended for developers who want to develop enterprise 53solutions for Android-powered devices. It discusses the various features 54provided by the Device Administration API to provide stronger security for 55employee devices that are powered by Android.</p> 56 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 69install on their devices. The device admin application enforces the desired 70policies. Here's how it works:</p> <ul> 71 <li>A system administrator writes a device admin application that enforces 72remote/local device security policies. These policies could be hard-coded into 73the app, or the application could dynamically fetch policies from a third-party 74server. </li> 75<li>The application is installed on users' devices. Android does 76not currently have an automated provisioning solution. Some of the ways a sysadmin might 77distribute 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 88and when this happens depends on how the application is implemented.</li> 89<li>Once users enable the device admin application, they are subject to 90its policies. Complying with those policies typically confers benefits, such as 91access 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—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 95password that violates the guidelines), it is up to the application to decide 96how to handle this. However, typically this will result in the user not being 97able to sync data.</p> 98<p>If a device attempts to connect to a server that requires policies not 99supported in the Device Administration API, the connection will not 100be allowed. The Device Administration API does not currently allow partial 101provisioning. In other words, if a device (for example, a legacy device) does 102not support all of the stated policies, there is no way to allow the 103device to connect.</p> 104<p>If a device contains multiple enabled admin applications, the strictest policy is 105enforced. There is no way to target a particular admin 106application.</p> 107<p>To uninstall an existing device admin application, users need to 108first 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 114adhere to a strict set of policies that govern the use of the device. The 115Device Administration API supports the policies listed in Table 1. 116Note that the Device Administration API currently only supports passwords for screen 117lock:</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 131can 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 135combination 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 147letters 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 154letters 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 160non-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 188users to update their passwords after a specified amount of time has elapsed. 189Introduced 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 195device wipes its data. The Device Administration API also allows administrators to 196remotely reset the device to factory defaults. This secures data in case the 197device 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 202pressed a button before the device locks the screen. When this happens, users 203need to enter their PIN or passwords again before they can use their devices and 204access 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. 209Introduced 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 215to be a permanent disabling. The camera can be enabled/disabled dynamically 216based 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 226Administration 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 <a 236href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/DeviceAdminSample.html"> 237Device Administration API 238sample</a>, which is included in the SDK samples. For information on downloading and 239installing the SDK samples, see <a 240href="{@docRoot}resources/samples/get.html"> 241Getting the Samples</a>. Here is the <a 242href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/DeviceAdminSample.html"> 243complete code</a> for 244the sample. </p> 245<p>The 246sample application offers a demo of device admin features. It presents users 247with a user interface that lets them enable the device admin application. Once 248they've enabled the application, they can use the buttons in the user interface 249to do the following:</p> 250<ul> 251 <li>Set password quality.</li> 252 <li>Specify requirements for the user's password, such as minimum length, the minimum number of 253 numeric characters it must contain, and so on.</li> 254 <li>Set the password. If the password does not conform to the specified 255policies, the system returns an error.</li> 256 <li>Set how many failed password attempts can occur before the device is wiped 257(that is, restored to factory settings).</li> 258<li>Set how long from now the password will expire.</li> 259<li>Set the password history length (<em>length</em> refers to number of old passwords stored in the history). 260This prevents users from reusing 261one of the last <em>n</em> passwords they previously used.</li> 262<li>Specify that the storage area should be encrypted, if the device supports it.</li> 263 <li>Set the maximum amount of inactive time that can elapse before the device 264locks.</li> 265 <li>Make the device lock immediately.</li> 266 <li>Wipe the device's data (that is, restore factory settings).</li> 267 <li>Disable the camera.</li> 268 269</ul> 270 271 272 273<img src="{@docRoot}images/admin/device-admin-app.png"/> 274 275<p class="img-caption"><strong>Figure 1.</strong> Screenshot of the Sample Application</p> 276 277 278 279<h2 id="developing">Developing a Device Administration Application</h2> 280 281<p>System administrators can use the Device Administration API to write an application 282that enforces remote/local device security policy enforcement. This section 283summarizes the steps involved in creating a device administration 284application.</p> 285 286<h3 id="manifest">Creating the manifest</h3> 287 288<p>To use the Device Administration API, the application's 289manifest must include the following:</p> 290<ul> 291 <li>A subclass of {@link android.app.admin.DeviceAdminReceiver} that includes the following: 292 <ul> 293 <li>The {@link android.Manifest.permission#BIND_DEVICE_ADMIN} permission.</li> 294 <li>The ability to respond to the {@link android.app.admin.DeviceAdminReceiver#ACTION_DEVICE_ADMIN_ENABLED} 295intent, expressed in the manifest as an intent filter.</li> 296 </ul> 297 </li> 298 <li>A declaration of security policies used in metadata.</li> 299</ul> 300<p>Here is an excerpt from the Device Administration sample manifest:</p> 301<pre><activity android:name=".app.DeviceAdminSample" 302 android:label="@string/activity_sample_device_admin"> 303 <intent-filter> 304 <action android:name="android.intent.action.MAIN" /> 305 <category android:name="android.intent.category.SAMPLE_CODE" /> 306 </intent-filter> 307</activity> 308<receiver android:name=".app.DeviceAdminSample$DeviceAdminSampleReceiver" 309 android:label="@string/sample_device_admin" 310 android:description="@string/sample_device_admin_description" 311 android:permission="android.permission.BIND_DEVICE_ADMIN"> 312 <meta-data android:name="android.app.device_admin" 313 android:resource="@xml/device_admin_sample" /> 314 <intent-filter> 315 <action android:name="android.app.action.DEVICE_ADMIN_ENABLED" /> 316 </intent-filter> 317</receiver></pre> 318 319 <p>Note that:</p> 320<ul> 321<li>The following attributes refer to string resources that for the sample application reside in 322<code>ApiDemos/res/values/strings.xml</code>. For more information about resources, see 323<a 324href="{@docRoot}guide/topics/resources/index.html">Application Resources</a>. 325<ul> 326<li><code>android:label="@string/activity_sample_device_admin"</code> refers to the 327user-readable label for the activity.</li> 328 329<li><code>android:label="@string/sample_device_admin"</code> refers to the 330user-readable label for the permission.</li> 331 332<li><code>android:description="@string/sample_device_admin_description"</code> refers to 333the user-readable description of the permission. A descripton is typically longer and more 334informative than 335a label.</li> 336</ul> 337 338 339<li><code>android:permission="android.permission.BIND_DEVICE_ADMIN" 340</code> is a permission that a {@link android.app.admin.DeviceAdminReceiver} subclass must 341have, to ensure that only the system can interact with the receiver (no application can be granted this permission). This 342prevents other applications from abusing your device admin app.</li> 343<li><code>android.app.action.DEVICE_ADMIN_ENABLED</code> is the primary 344action that a {@link android.app.admin.DeviceAdminReceiver} subclass must handle to be 345allowed to manage a device. This is set to the receiver when the user enables 346the device admin app. Your code typically handles this in 347{@link android.app.admin.DeviceAdminReceiver#onEnabled onEnabled()}. To be supported, the receiver must also 348require the {@link android.Manifest.permission#BIND_DEVICE_ADMIN} permission so that other applications 349cannot abuse it. </li> 350<li>When a user enables the device admin application, that gives the receiver 351permission to perform actions in response to the broadcast of particular system 352events. When suitable event arises, the application can impose a policy. For 353example, if the user attempts to set a new password that doesn't meet the policy 354requirements, the application can prompt the user to pick a different password 355that does meet the requirements.</li> 356 357 <li><code>android:resource="@xml/device_admin_sample"</code> 358declares the security policies used in metadata. The metadata provides additional 359information specific to the device administrator, as parsed by the {@link 360android.app.admin.DeviceAdminInfo} class. Here are the contents of 361<code>device_admin_sample.xml</code>:</li> 362</ul> 363<pre><device-admin xmlns:android="http://schemas.android.com/apk/res/android"> 364 <uses-policies> 365 <limit-password /> 366 <watch-login /> 367 <reset-password /> 368 <force-lock /> 369 <wipe-data /> 370 <expire-password /> 371 <encrypted-storage /> 372 <disable-camera /> 373 </uses-policies> 374</device-admin> 375</pre> 376<p> In designing your device administration application, you don't need to 377include all of the policies, just the ones that are relevant for your app. 378</p> 379For more discussion of the manifest file, see the <a 380href="{@docRoot}guide/topics/manifest/manifest-intro.html">Android Developers Guide</a>. 381 382 383 384<h3 id="code">Implementing the code</h3> 385 386<p>The Device Administration API includes the following classes:</p> 387<dl> 388 <dt>{@link android.app.admin.DeviceAdminReceiver}</dt> 389 <dd>Base class for implementing a device administration component. This class provides 390a convenience for interpreting the raw intent actions that are sent by the 391system. Your Device Administration application must include a 392{@link android.app.admin.DeviceAdminReceiver} subclass.</dd> 393 <dt>{@link android.app.admin.DevicePolicyManager}</dt> 394<dd>A class for managing policies enforced on a device. Most clients of 395this class must have published a {@link android.app.admin.DeviceAdminReceiver} that the user 396has currently enabled. The {@link android.app.admin.DevicePolicyManager} manages policies for 397one or more {@link android.app.admin.DeviceAdminReceiver} instances</dd> 398 <dt>{@link android.app.admin.DeviceAdminInfo}</dt> 399<dd>This class is used to specify metadata 400for a device administrator component.</dd> 401</dl> 402<p>These classes provide the foundation for a fully functional device administration application. 403The rest of this section describes how you use the {@link 404android.app.admin.DeviceAdminReceiver} and 405{@link android.app.admin.DevicePolicyManager} APIs to write a device admin application.</p> 406 407<h4 id="receiver">Subclassing DeviceAdminReceiver</h4> 408<p>To create a device admin application, you must subclass 409{@link android.app.admin.DeviceAdminReceiver}. The {@link android.app.admin.DeviceAdminReceiver} class 410consists of a series of callbacks that are triggered when particular events 411occur.</p> 412<p>In its {@link android.app.admin.DeviceAdminReceiver} subclass, the sample application 413simply displays a {@link android.widget.Toast} notification in response to particular 414events. For example:</p> 415<pre>public class DeviceAdminSample extends DeviceAdminReceiver { 416 417 void showToast(Context context, String msg) { 418 String status = context.getString(R.string.admin_receiver_status, msg); 419 Toast.makeText(context, status, Toast.LENGTH_SHORT).show(); 420 } 421 422 @Override 423 public void onEnabled(Context context, Intent intent) { 424 showToast(context, context.getString(R.string.admin_receiver_status_enabled)); 425 } 426 427 @Override 428 public CharSequence onDisableRequested(Context context, Intent intent) { 429 return context.getString(R.string.admin_receiver_status_disable_warning); 430 } 431 432 @Override 433 public void onDisabled(Context context, Intent intent) { 434 showToast(context, context.getString(R.string.admin_receiver_status_disabled)); 435 } 436 437 @Override 438 public void onPasswordChanged(Context context, Intent intent) { 439 showToast(context, context.getString(R.string.admin_receiver_status_pw_changed)); 440 } 441... 442}</pre> 443 444 445<h4 id="enabling">Enabling the application</h4> 446<p>One of the major events a device admin application has to handle is the user 447enabling the application. The user must explicitly enable the application for 448the policies to be enforced. If the user chooses not to enable the application 449it will still be present on the device, but its policies will not be enforced, and the user will not 450get any of the application's benefits.</p> 451<p>The process of enabling the application begins when the user performs an 452action that triggers the {@link android.app.admin.DevicePolicyManager#ACTION_ADD_DEVICE_ADMIN} 453intent. In the 454sample application, this happens when the user clicks the <strong>Enable 455Admin</strong> checkbox. </p> 456<p>When the user clicks the <strong>Enable Admin</strong> checkbox, the display 457changes to prompt the user to activate the device admin application, as shown in figure 4582.</p> 459 460<img src="{@docRoot}images/admin/device-admin-activate-prompt.png"/> 461<p class="img-caption"><strong>Figure 2.</strong> Sample Application: Activating the Application</p> 462 463<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 464{@link android.preference.Preference.OnPreferenceChangeListener#onPreferenceChange(android.preference.Preference, java.lang.Object) onPreferenceChange()} 465callback. 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 466changes to prompt the user to activate the device admin application, as shown in figure 4672. Otherwise, the device admin application is disabled. </p> 468 469<pre>@Override 470 public boolean onPreferenceChange(Preference preference, Object newValue) { 471 if (super.onPreferenceChange(preference, newValue)) { 472 return true; 473 } 474 boolean value = (Boolean) newValue; 475 if (preference == mEnableCheckbox) { 476 if (value != mAdminActive) { 477 if (value) { 478 // Launch the activity to have the user enable our admin. 479 Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN); 480 intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, mDeviceAdminSample); 481 intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION, 482 mActivity.getString(R.string.add_admin_extra_app_text)); 483 startActivityForResult(intent, REQUEST_CODE_ENABLE_ADMIN); 484 // return false - don't update checkbox until we're really active 485 return false; 486 } else { 487 mDPM.removeActiveAdmin(mDeviceAdminSample); 488 enableDeviceCapabilitiesArea(false); 489 mAdminActive = false; 490 } 491 } 492 } else if (preference == mDisableCameraCheckbox) { 493 mDPM.setCameraDisabled(mDeviceAdminSample, value); 494 ... 495 } 496 return true; 497 }</pre> 498 499 500<p>The line 501<code>intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, 502mDeviceAdminSample)</code> states that <code>mDeviceAdminSample</code> (which is 503a {@link android.app.admin.DeviceAdminReceiver} component) is the target policy. 504This line invokes the user interface shown in figure 2, which guides users through 505adding the device administrator to the system (or allows them to reject it).</p> 506 507<p>When the application needs to perform an operation that is contingent on the 508device admin application being enabled, it confirms that the application is 509active. To do this it uses the {@link android.app.admin.DevicePolicyManager} method 510{@link android.app.admin.DevicePolicyManager#isAdminActive(android.content.ComponentName) isAdminActive()}. Notice that the {@link android.app.admin.DevicePolicyManager} 511method {@link android.app.admin.DevicePolicyManager#isAdminActive(android.content.ComponentName) isAdminActive()} takes a {@link android.app.admin.DeviceAdminReceiver} 512component as its argument:</p> 513 514<pre> 515DevicePolicyManager mDPM; 516... 517private boolean isActiveAdmin() { 518 return mDPM.isAdminActive(mDeviceAdminSample); 519} 520</pre> 521 522 523 524<h3 id="admin_ops">Managing policies</h3> 525<p>{@link android.app.admin.DevicePolicyManager} is a public class for managing policies 526enforced on a device. {@link android.app.admin.DevicePolicyManager} manages policies for one 527or more {@link android.app.admin.DeviceAdminReceiver} instances. </p> 528<p>You get a handle to the {@link android.app.admin.DevicePolicyManager} as follows: </p> 529<pre> 530DevicePolicyManager mDPM = 531 (DevicePolicyManager)getSystemService(Context.DEVICE_POLICY_SERVICE); 532</pre> 533<p>This section describes how to use {@link android.app.admin.DevicePolicyManager} to perform 534 administrative tasks:</p> 535<ul> 536 <li><a href="#pwd">Set password policies</a></li> 537 <li><a href="#lock">Set device lock</a></li> 538 <li><a href="#wipe">Perform data wipe</a></li> 539</ul> 540 541<h4 id="pwd">Set password policies</h4> 542<p>{@link android.app.admin.DevicePolicyManager} includes APIs for setting and enforcing the 543device password policy. In the Device Administration API, the password only applies to 544screen lock. This section describes common password-related tasks.</p> 545 546<h5>Set a password for the device</h5> 547<p>This code displays a user interface prompting the user to set a password:</p> 548<pre>Intent intent = new Intent(DevicePolicyManager.ACTION_SET_NEW_PASSWORD); 549startActivity(intent); 550</pre> 551 552<h5>Set the password quality</h5> 553<p>The password quality can be one of the following {@link android.app.admin.DevicePolicyManager} constants: </p> 554<dl> 555 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_ALPHABETIC}</dt><dd>The user must enter a 556password containing at least alphabetic (or other symbol) characters.</dd> 557 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_ALPHANUMERIC}</dt><dd>The user must enter a 558password containing at least <em>both</em> numeric <em>and</em> alphabetic (or 559other symbol) characters.</dd> 560 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_NUMERIC}</dt><dd>The user must enter a password 561containing at least numeric characters.</dd> 562<dt>{@link 563android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_COMPLEX}</dt><dd>The user 564must have entered a password containing at least a letter, a numerical digit and 565a special symbol.</dd> 566<dt>{@link 567android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_SOMETHING}</dt><dd>The 568policy requires some kind 569of password, but doesn't care what it is.</dd> 570 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_UNSPECIFIED}</dt><dd> 571 The policy has no requirements for the password. </dd> 572</dl> 573<p>For example, this is how you would set the password policy to require an alphanumeric password:</p> 574<pre> 575DevicePolicyManager mDPM; 576ComponentName mDeviceAdminSample; 577... 578mDPM.setPasswordQuality(mDeviceAdminSample, DevicePolicyManager.PASSWORD_QUALITY_ALPHANUMERIC); 579</pre> 580 581<h5>Set password content requirements</h5> 582 583<p>Beginning with Android 3.0, the {@link android.app.admin.DevicePolicyManager} class 584includes methods that let you fine-tune the contents of the password. For 585example, you could set a policy that states that passwords must contain at least 586<em>n</em> uppercase letters. Here are the methods for fine-tuning a password's 587contents:</p> 588<ul> 589 590<li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumLetters(android.content.ComponentName,int) setPasswordMinimumLetters()}</li> 591 592<li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumLowerCase(android.content.ComponentName,int) setPasswordMinimumLowerCase()}</li> 593 594<li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumUpperCase(android.content.ComponentName,int) setPasswordMinimumUpperCase()}</li> 595 596<li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumNonLetter(android.content.ComponentName,int) setPasswordMinimumNonLetter()}</li> 597 598<li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumNumeric(android.content.ComponentName,int) setPasswordMinimumNumeric()}</li> 599 600<li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumSymbols(android.content.ComponentName,int) setPasswordMinimumSymbols()}</li> 601</ul> 602<p>For example, this snippet states that the password must have at least 2 uppercase letters:</p> 603<pre> 604DevicePolicyManager mDPM; 605ComponentName mDeviceAdminSample; 606int pwMinUppercase = 2; 607... 608mDPM.setPasswordMinimumUpperCase(mDeviceAdminSample, pwMinUppercase);</pre> 609 610 611<h5>Set the minimum password length</h5> 612<p>You can specify that a password must be at least the specified minimum 613length. For example:</p> 614<pre>DevicePolicyManager mDPM; 615ComponentName mDeviceAdminSample; 616int pwLength; 617... 618mDPM.setPasswordMinimumLength(mDeviceAdminSample, pwLength); 619</pre> 620 621<h5>Set maximum failed password attempts</h5> 622<p>You can set the maximum number of allowed failed password attempts before the 623device is wiped (that is, reset to factory settings). For example:</p> 624<pre>DevicePolicyManager mDPM; 625ComponentName mDeviceAdminSample; 626int maxFailedPw; 627 ... 628mDPM.setMaximumFailedPasswordsForWipe(mDeviceAdminSample, maxFailedPw);</pre> 629 630<h5 id="expiration">Set password expiration timeout</h5> 631<p>Beginning with Android 3.0, you can use the 632{@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()} 633method 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> 634 635<pre>DevicePolicyManager mDPM; 636ComponentName mDeviceAdminSample; 637long pwExpiration; 638... 639mDPM.setPasswordExpirationTimeout(mDeviceAdminSample, pwExpiration); 640</pre> 641 642<h5 id="history">Restrict password based on history</h5> 643 644<p>Beginning with Android 3.0, you can use the 645{@link android.app.admin.DevicePolicyManager#setPasswordHistoryLength(android.content.ComponentName,int) setPasswordHistoryLength()} 646method to limit users' 647ability to reuse old passwords. This method takes a <em>length</em> 648parameter, which specifies how many old 649passwords are stored. When this policy is active, users cannot enter a new 650password that matches the last <em>n</em> passwords. This prevents 651users from using the same password over and over. This policy is typically used 652in conjunction with 653{@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()}, 654which forces users 655to update their passwords after a specified amount of time has elapsed. </p> 656 657<p>For example, this snippet prohibits users from reusing any of their last 5 passwords:</p> 658 659<pre>DevicePolicyManager mDPM; 660ComponentName mDeviceAdminSample; 661int pwHistoryLength = 5; 662... 663mDPM.setPasswordHistoryLength(mDeviceAdminSample, pwHistoryLength); 664</pre> 665 666<h4 id="lock">Set device lock</h4> 667<p>You can set the maximum period of user inactivity that can occur before the 668device locks. For example:</p> 669<pre> 670DevicePolicyManager mDPM; 671ComponentName mDeviceAdminSample; 672... 673long timeMs = 1000L*Long.parseLong(mTimeout.getText().toString()); 674mDPM.setMaximumTimeToLock(mDeviceAdminSample, timeMs); 675</pre> 676<p>You can also programmatically tell the device to lock immediately:</p> 677<pre> 678DevicePolicyManager mDPM; 679mDPM.lockNow();</pre> 680 681 682 683<h4 id="wipe">Perform data wipe</h4> 684 685<p>You can use the {@link android.app.admin.DevicePolicyManager} method 686{@link android.app.admin.DevicePolicyManager#wipeData wipeData()} to reset the device to factory settings. This is useful 687if the device is lost or stolen. Often the decision to wipe the device is the 688result of certain conditions being met. For example, you can use 689{@link android.app.admin.DevicePolicyManager#setMaximumFailedPasswordsForWipe setMaximumFailedPasswordsForWipe()} to state that a device should be 690wiped after a specific number of failed password attempts.</p> 691<p>You wipe data as follows:</p> 692<pre> 693DevicePolicyManager mDPM; 694mDPM.wipeData(0);</pre> 695<p>The {@link android.app.admin.DevicePolicyManager#wipeData wipeData()} method takes as its parameter a bit mask of 696additional options. Currently the value must be 0. </p> 697 698<h4>Disable camera</h4> 699<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> 700<p>You control whether the camera is disabled by using the 701{@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> 702 703<pre>private CheckBoxPreference mDisableCameraCheckbox; 704DevicePolicyManager mDPM; 705ComponentName mDeviceAdminSample; 706... 707mDPM.setCameraDisabled(mDeviceAdminSample, mDisableCameraCheckbox.isChecked());<br /> 708</pre> 709 710 711<h4 id=storage">Storage encryption</h4> 712<p>Beginning with Android 3.0, you can use the 713{@link android.app.admin.DevicePolicyManager#setStorageEncryption(android.content.ComponentName,boolean) setStorageEncryption()} 714method to set a policy requiring encryption of the storage area, where supported.</p> 715 716<p>For example:</p> 717 718<pre> 719DevicePolicyManager mDPM; 720ComponentName mDeviceAdminSample; 721... 722mDPM.setStorageEncryption(mDeviceAdminSample, true); 723</pre> 724<p> 725See the <a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/DeviceAdminSample.html"> Device Administration API sample</a> for a complete 726example of how to enable storage encryption.</p> 727