page.title=Support Package @jd:body

In this document

  1. Revisions
  2. Downloading the Support Package
  3. Setting Up a Project to Use a Library
  4. Using the v4 Library APIs
  5. Reference Docs
  6. Samples

See also

  1. Optimizing Apps for Android 3.0
  2. Google I/O App source code

Minimum API level supported: 4

The Support Package includes static "support libraries" that you can add to your Android application in order to use APIs that are either not available for older platform versions or that offer "utility" APIs that aren't a part of the framework APIs. The goal is to simplify your development by offering more APIs that you can bundle with your application so you can worry less about platform versions.

Note: The Support Package includes more than one support library. Each one has a different minimum API level. For example, one library requires API level 4 or higher, while another requires API level 13 or higher (v13 is a superset of v4 and includes additional support classes to work with v13 APIs). The minimum version is indicated by the directory name, such as {@code v4/} and {@code v13/}.

Revisions

The sections below provide notes about successive releases of the Support Package, as denoted by revision number.

Support Package, revision 4 (October 2011)

Changes for v4 support library:
  • Support for Accessiblity APIs:
    • Added AccessibilityDelegateCompat to support {@link android.view.View.AccessibilityDelegate}.
    • Added AccessibilityEventCompat to support {@link android.view.accessibility.AccessibilityEvent}.
    • Added AccessibilityManagerCompat to support {@link android.view.accessibility.AccessibilityManager}.
    • Added AccessibilityNodeInfoCompat to support {@link android.view.accessibility.AccessibilityNodeInfo}.
    • Added AccessibilityRecordCompat to support {@link android.view.accessibility.AccessibilityRecord}.
    • Added AccessibilityServiceInfoCompat to support {@link android.accessibilityservice.AccessibilityServiceInfo}.
    • Added ViewGroupCompat to support accessibility features in {@link android.view.ViewGroup}.
    • Modified ViewCompat to support accessibility features in {@link android.view.View}.
  • Added EdgeEffectCompat to support {@link android.widget.EdgeEffect}.
  • Added LocalBroadcastManager to allow applications to easily register for and receive intents within a single application without broadcasting them globally.
  • Added support in ViewCompat to check for and set overscroll modes for {@link android.view.View}s on Android 2.3 and later.
  • Changes to Fragment APIs:
    • Added new APIs to control the visibility of new menus.
    • Added custom animation APIs.
    • Added APIs in FragmentActivity to retain custom, non-configuration instance data.
    • Various bug fixes.
  • Changes to ViewPager:
    • Added support for margins between pages. An optional {@link android.graphics.drawable.Drawable} can be provided to fill the margins.
    • Added support for {@link android.widget.EdgeEffect}.
    • Added support for keyboard navigation
    • Added support to control how many pages are kept to either side of the current page.
    • Improved touch physics.
  • Fixed a {@link android.content.Loader} bug that caused issues in canceling {@link android.os.AsyncTask}s when running on Froyo and older versions of the platform. The support code now uses its own version of {@link android.os.AsyncTask} to keep the same behavior on all platform versions.

Compatibility Package, revision 3 (July 2011)

Changes for v4 support library:
  • Adds support for {@link android.app.Fragment.SavedState}
  • Adds {@code MotionEventCompat} to support newer {@link android.view.MotionEvent} APIs
  • Adds {@code VelocityTrackerCompat} to support a newer {@link android.view.VelocityTracker} APIs
  • Adds {@code ViewConfigurationCompat} to support a newer {@link android.view.ViewConfiguration} APIs
  • All new APIs (available only in the support library) that allow you to create UIs with horizontal paging, allowing users to swipe left and right between content views. Classes to support this include:
    • {@code ViewPager}: A {@link android.view.ViewGroup} that manages the layout for the child views, which the user can swipe between.
    • {@code PagerAdapter}: An adapter that populates the {@code ViewPager} with the views that represent each page.
    • {@code FragmentPagerAdapter}: An extension of {@code PagerAdapter} for flipping between fragments.
    • {@code FragmentStatePagerAdapter}: An extension of {@code PagerAdapter} for flipping between fragments that uses the library's support for {@link android.app.Fragment.SavedState}.
New v13 support library:
  • Includes the {@code FragmentPagerAdapter} and {@code FragmentStatePagerAdapter} to support the horizontal paging.

    These are exactly the same as the APIs added to the v4 support library, but rely on other platform components in Android 3.2. Use this library instead of v4 if you're developing for Android 3.2 and higher (all other APIs in the v4 library are already available with API level 13).

Compatibility Package, revision 2 (May 2011)

Changes for v4 library:
  • Support for fragment animations
  • Fix {@code Fragment.onActivityResult()} bug

Compatibility Package, revision 1 (March 2011)

Initial release with the v4 library.

Downloading the Support Package

The Support Package is provided as a downloadable package from the Android SDK and AVD Manager. To install:

  1. Launch the SDK and AVD Manager.

    From Eclipse, you can select Window > Android SDK and AVD Manager. Or, launch {@code SDK Manager.exe} from the {@code <sdk>/} directory (on Windows only) or {@code android} from the {@code <sdk>/tools/} directory.

  2. Expand the Android Repository, check Android Support package and click Install selected.
  3. Proceed to install the package.

When done, all files (including source code, samples, and the {@code .jar} files) are saved into the <sdk>/extras/android/support/ directory. This directory contains each of the different support libraries, such as the library for API level 4 and up and the library for API level 13 and up, each named with the respective version (such as {@code v4/}).

Setting Up a Project to Use a Library

To add one of the libraries to your Android project:

  1. In your Android project, create a directory named {@code libs} at the root of your project (next to {@code src/}, {@code res/}, etc.)
  2. Locate the JAR file for the library you want to use and copy it into the {@code libs/} directory.

    For example, the library that supports API level 4 and up is located at {@code <sdk>/extras/android/support/v4/android-support-v4.jar}.

  3. Add the JAR to your project build path.

    In Eclipse, right-click the JAR file in the Package Explorer, select Build Path > Add to Build Path. You should then see the JAR file appear in a new directory called Referenced Libraries.

Your application is now ready to use the library APIs. All the provided APIs are available in the {@code android.support} package (for example, {@code android.support.v4}).

Tip: To see the library APIs in action, take a look at the sample apps in {@code extras/android/support/<version>/samples/}.

Warning: Be certain that you not confuse the standard {@code android} packages with those in {@code android.support} library. Some code completion tools might get this wrong, especially if you're building against recent versions of the platform. To be safe, keep your build target set to the same version as you have defined for your {@code android:minSdkVersion} and double check the import statements for classes that also exist in the support library, such as {@code SimpleCursorAdapter}.

Using the v4 Library APIs

The support library for v4 provides access to several classes introduced with Android 3.0 and beyond, plus some updated version of existing classes, and even some APIs that currently don't exist in the Android platform. Some of the most useful and notable classes that have counterparts in the v4 support library are:

For each of the classes above (and others not listed), the APIs work almost exactly the same as the counterparts in the latest Android platform. Thus, you can usually refer to the online documentation for information about the supported APIs. There are some differences, however. Most notably:

Tip: To enable the Holographic theme on devices running Android 3.0 or higher, declare in your manifest file that your application targets API level 11. For example:

<uses-sdk android:minSdkVersion="4" android:targetSdkVersion="11" />

This way, your application automatically receives the Holographic theme and the Action Bar for each activity when running on Android 3.0 and higher.

For more information about how you can optimize your application for the latest Android-powered devices, read Optimizing Apps for Android 3.0.

Reference Docs

The libraries currently do not provide reference documentation for the included APIs. To generate your own set using the {@code javadoc} tool, perform the following from a command (as appropriate for the library version you're using). In this example, documentation is generated for the v4 library:

cd <sdk>/extras/android/support/v4/
mkdir docs
javadoc -sourcepath src/java/ -subpackages android.support.v4 -d docs

Open the {@code docs/index.html} file to begin browsing the generated documentation.

Samples

If you want to see some code that uses the support libraries, samples are included with the Support Package, inside each support library directory. For example, at {@code extras/android/support/v4/samples/}.

Additionally, the Google I/O App is a complete application that uses the v4 support library to provide a single APK for both handsets and tablets and also demonstrates some of Android's best practices in Android UI design.