The Android SDK Manager separates the SDK tools, platforms, and other components into packages for easy access and management. You can also customize which sites the SDK Manager checks for new or updated SDK packages and add-on tools. For example, you can configure the SDK Manager to automatically check for updates and notify you when an installed SDK Tools package is updated. When you receive such a notification, you can then quickly decide whether to download the changes.
By default, Android Studio does not check for Android SDK updates. To enable automatic Android SDK checking:
Choose File > Settings > Appearance & Behavior > System Settings > Updates.
Check the Automatically check updates for Android SDK checkbox and select an update channel.
Click OK or Apply to enable the update checking.
You can launch the SDK Manager in one of the following ways:
From the Android Studio File menu: File > Settings > Appearance & Behavior > System Settings > Android SDK.
From the Android Studio Tools menu: Tools > Android > SDK Manager.
From the SDK Manager icon () in the menu bar.
Tip: The standalone SDK Manager is still available from the command line, but we recommend it only for use with Eclipse ADT and standalone SDK installations.
By default, the SDK Manager installs the latest packages and tools. Click the checkbox next to each additional SDK platform and tool that you want to install. Clear the checkbox to uninstall a SDK platform or tool. Click Apply or OKto update the packages and tools.
Tip: When an update is available for an installed package, a hyphen (-) appears in the checkbox next to the package. A download icon () also appears next to the checkbox to indicate the pending update. An update icon () appears next to the checkbox to indicate pending removals.
Click the SDK Update Sites tab to manage which SDK sites Android Studio checks for tool and add-on updates.
Figure 1. The Android SDK Manager shows the SDK platforms and packages that are available and installed along with the SDK update sites.
There are several different packages available for the Android SDK. The table below describes most of the available packages and where they're located in your SDK directory once you download them.
Recommended Packages
Here's an outline of the packages required and those we recommend you use:
SDK Tools
Required. Your new SDK installation installs the latest version. Be sure to respond to the Android Studio update prompts to keep your SDK Tools up-to-date.
SDK Platform-tools
Required. Your new SDK installation installs the latest stable version. Be sure to respond to the Android Studio update prompts to keep your SDK Platform-tools up-to-date.
SDK Platform
Required. At least one platform is required in your environment so you're able to compile your application. In order to provide the best user experience on the latest devices, we recommend that you use the latest platform version as your build target. You'll still be able to run your app on older versions, but you must build against the latest version in order to use new features when running on devices with the latest version of Android.
The SDK Manager downloads the latest Android version. It also downloads the earliest version of Android (Android 2.2 (API level 8)) that we recommend that your app support.
System Image
Recommended. Although you might have one or more Android-powered devices on which to test your app, it's unlikely you have a device for every version of Android your app supports. It's a good practice to download system images for all versions of Android your app supports and test your app running on them with theAndroid emulator. Each SDK platform package contains the supported system images. Click Show Package Details to display the available system images for each available platform. You can also download system images when creating Android Virtual Devices (AVDs) in theAVD Manager.
Android Support Library
Recommended. Includes a static library that allows you to use some of the latest Android APIs (such as fragments, plus others not included in the framework at all) on devices running a platform version as old as Android 1.6. All of the activity templates available when creating a new project with the ADT Pluginrequire this. For more information, read Support Library.
Android Support Repository
Recommended. Includes local Maven repository for Support libraries.
Google Play services
Recommended. Includes Google Play services client library and sample code.
Google Repository
Recommended. Includes local Maven repository for Google libraries.
Tip: For easy access to the SDK tools from a command line, add the location of the SDK's tools/ andplatform-tools to your PATH environment variable.
The above list is not comprehensive and you can add new sites to download additional packages from third parties.
In some cases, an SDK package may require a specific minimum revision of another package or SDK tool. The development tools will notify you with warnings if there is dependency that you need to address. The Android SDK Manager also enforces dependencies by requiring any packages that are needed by those you have selected.
Adding New Sites
The SDK Update Sites tab displays the sites that Android Studio checks for Android SDK and third-party updates. You can add other sites that host their own Android SDK add-ons, then download the SDK add-ons from those sites.
For example, a mobile carrier or device manufacturer might offer additional API libraries that are supported by their own Android-powered devices. In order to develop using their libraries, you must install their Android SDK add-on, if it's not already available as a third-party add-on.
If a carrier or device manufacturer has hosted an SDK add-on repository file on their website, follow these steps to add their site to the Android SDK Manager:
Click the SDK Update Sites tab.
Click the Add icon in the tools area and enter the name and URL of the
add-onsite.Click OK.
Make sure the checkbox is checked in the Enabled column.
Click OK or Apply.
Any SDK packages available from the site appear in the SDK Platforms orSDK Tools tabs