1page.title=<uses-sdk> 2parent.title=The AndroidManifest.xml File 3parent.link=manifest-intro.html 4@jd:body 5 6<dl class="xml"> 7<dt>syntax:</dt> 8<dd><pre> 9<uses-sdk android:<a href="#min">minSdkVersion</a>="<i>integer</i>" 10 android:<a href="#target">targetSdkVersion</a>="<i>integer</i>" 11 android:<a href="#max">maxSdkVersion</a>="<i>integer</i>" /></pre></dd> 12 13<dt>contained in:</dt> 14<dd><code><a href="{@docRoot}guide/topics/manifest/manifest-element.html"><manifest></a></code></dd> 15 16<dt>description:</dt> 17<dd>Lets you express an application's compatibility with one or more versions of the Android platform, 18by means of an API Level integer. The API Level expressed by an application will be compared to the 19API Level of a given Android system, which may vary among different Android devices. 20</p> 21 22<p>Despite its name, this element is used to specify the API Level, <em>not</em> 23the version number of the SDK (software development kit) or Android platform. 24The API Level is always a single integer. You cannot derive the API Level from 25its associated Android version number (for example, it is not the same as the 26major version or the sum of the major and minor versions).</p> 27 28<p>For more information, read about 29<a href="{@docRoot}guide/appendix/api-levels.html">Android API Levels</a> and 30<a href="{@docRoot}guide/publishing/versioning.html">Versioning Your Applications</a>. 31</p></dd> 32 33 <div class="sidebox-wrapper" xstyle="margin-bottom:2em;margin-top:.5em;width:90%;"> 34 <img id="rule" src="{@docRoot}assets/images/grad-rule-qv.png"> 35 <div id="qv-sub-rule"> 36 <img src="{@docRoot}assets/images/icon_market.jpg" style="float:left;margin:0;padding:0;"> 37 <p style="color:#669999;">Android Market and <uses-sdk> attributes</p> 38 <p>Android Market filters the applications that are visible to users, so 39that users can only see and download applications that are compatible with their 40devices. One of the ways Market filters applications is by Android 41version-compatibility. To do this, Market checks the <code><uses-sdk></code> 42attributes in each application's manifest to establish its version-compatibility 43range, then shows or hides the application based on a comparison with the API 44Level of the user's Android system version. For more information, see <a 45href="{@docRoot}guide/appendix/market-filters.html">Market Filters</a>.</p> 46 </div> 47</div> 48 49<dt>attributes:</dt> 50 51<dd> 52<dl class="attr"> 53 <dt><a name="min"></a>{@code android:minSdkVersion}</dt> 54 <dd>An integer designating the minimum API Level required 55 for the application to run. The Android system will prevent the user from installing 56 the application if the system's API Level is lower than the value specified in 57 this attribute. You should always declare this attribute. 58 59 <p class="caution"><strong>Caution:</strong> If you do not declare this 60 attribute, the system assumes a default value of "1", which indicates that your 61 application is compatible with all versions of Android. If your application is 62 <em>not</em> compatible with all versions (for instance, it uses APIs introduced 63 in API Level 3) and you have not declared the proper <code>android:minSdkVersion</code>, 64 then when installed on a system with an API Level less than 3, the application 65 will crash during runtime when attempting to access the unavailable APIs. For 66 this reason, be certain to declare the appropriate API Level in the 67 <code>minSdkVersion</code> attribute.</p> 68 </dd> 69 70 <dt><a name="target"></a>{@code android:targetSdkVersion}</dt> 71 <dd>An integer designating the API Level that the application is targetting. 72 73 <p>With this attribute set, the application says that it is able to run on 74 older versions (down to {@code minSdkVersion}), but was explicitly tested to 75 work with the version specified here. Specifying this target version allows the 76 platform to disable compatibility settings that are not required for the target 77 version (which may otherwise be turned on in order to maintain 78 forward-compatibility) or enable newer features that are not available to older 79 applications. This does not mean that you can program different features for 80 different versions of the platform—it simply informs the platform that you 81 have tested against the target version and the platform should not perform any 82 extra work to maintain forward-compatibility with the target version.</p> 83 84 <p>Introduced in: API Level 4</p> 85 </dd> 86 87 <dt><a name="max"></a>{@code android:maxSdkVersion}</dt> 88 <dd>An integer designating the maximum API Level on which the application is 89 designed to run. 90 91 <p>In Android 1.5, 1.6, 2.0, and 2.0.1, the system checks the value of this 92 attribute when installing an application and when revalidating the application 93 after a system update. In either case, if the application's 94 <code>android:maxSdkVersion</code> attribute is lower than the API Level used by 95 the system itself, then the system will not allow the application to be 96 installed. In the case of revalidation after system update, this effectively 97 removes your application from the device. 98 99 <p>To illustrate how this attribute can affect your application after system 100 updates, consider the following example: </p> 101 102 <p>An application declaring <code>android:maxSdkVersion="5"</code> in its 103 manifest is published on Android Market. A user whose device is running Android 104 1.6 (API Level 4) downloads and installs the app. After a few weeks, the user 105 receives an over-the-air system update to Android 2.0 (API Level 5). After the 106 update is installed, the system checks the application's 107 <code>android:maxSdkVersion</code> and successfully revalidates it. The 108 application functions as normal. However, some time later, the device receives 109 another system update, this time to Android 2.0.1 (API Level 6). After the 110 update, the system can no longer revalidate the application because the system's 111 own API Level (6) is now higher than the maximum supported by the application 112 (5). The system prevents the application from being visible to the user, in 113 effect removing it from the device.</p> 114 115 <p class="warning"><strong>Warning:</strong> Declaring this attribute is not 116 recommended. First, there is no need to set the attribute as means of blocking 117 deployment of your application onto new versions of the Android platform as they 118 are released. By design, new versions of the platform are fully 119 backward-compatible. Your application should work properly on new versions, 120 provided it uses only standard APIs and follows development best practices. 121 Second, note that in some cases, declaring the attribute can <strong>result in 122 your application being removed from users' devices after a system 123 update</strong> to a higher API Level. Most devices on which your appplication 124 is likely to be installed will receive periodic system updates over the air, so 125 you should consider their effect on your application before setting this 126 attribute.</p> 127 128 <p style="margin-bottom:1em;">Introduced in: API Level 4</p> 129 130 <div class="special">Future versions of Android (beyond Android 2.0.1) will no 131longer check or enforce the <code>android:maxSdkVersion</code> attribute during 132installation or revalidation. Android Market will continue to use the attribute 133as a filter, however, when presenting users with applications available for 134download. </div> 135 </dd> 136 137 138</dl></dd> 139 140<!-- ##api level indication## --> 141<dt>introduced in:</dt> 142<dd>API Level 1</dd> 143 144</dl> 145
