Hello, Stack Overflow!

Over the past year, an Android presence has been growing on a relatively new technical Q&A web site called Stack Overflow. The site was designed specifically for programmers, with features like syntax highlighting, tagging, user reputation, and community editing. It's attracted a loyal software developer community, and developers continue to express great praise for this new tool. Well, the Android team has been listening...and we agree.

Today, I'm happy to announce that we're working with Stack Overflow to improve developer support, especially for developers new to Android. In essence, the Android tag on Stack Overflow will become an official Android app development Q&A medium. We encourage you to post your beginner-level technical questions there. It's also important to point out that we don't plan to change the android-developers group, so intermediate and expert users should still feel free to post there.

I think that this will be a great new resource for novice Android developers, and our team is really excited to participate in the growth of the Android developer community on Stack Overflow. I hope to see you all there!

New resources and sample code on developer.android.com

Hey Android developers—if you've visited the online Android SDK documentation recently, you may have noticed a few changes. That's right, there's a new Resources tab, which was designed to take some of the load off the Developer's Guide. We've moved a number of existing resources to the Resources tab, including tutorials, sample code, and FAQs. We've also formalized a few of our most popular developer blog posts into technical articles; watch for more of these to appear in the future.

In addition, we just released a new batch of sample code, available now as a ZIP file download on the samples index page. And we're working on updating the way in which we distribute official sample code; more on that some other time.

The new sample code includes:

• Multiple Resolutions: a simple example showing how to use resource directory qualifiers to support multiple screen configurations and Android SDK versions.
• Wiktionary and WiktionarySimple: sample applications that illustrate how to create an interactive home screen widget.
• Contact Manager: an example on using the new ContactsContract interface to query and manipulate a user's various accounts and contact providers.
• Bluetooth Chat: a fun little demo that allows two users to have a 1 on 1 chat over Bluetooth. It demonstrates how to discover devices, initiate a connection, and transfer data.
• API Demos > App > Activity > QuickContactsDemo: a demo showing how to use the android.widget.QuickContactsBadge class, new in Android 2.0.
• API Demos > App > Activity > SetWallpaper: a demo showing how to use the new android.app.WallpaperManager class to allow users to change the system wallpaper.
• API Demos > App > Text-To-Speech: a sample using Text-To-Speech (speech synthesis) to make your application talk.
• NotePad (now with Live Folders): this sample now includes code for creating Live Folders.

We hope these new samples can be a valuable resource for learning some of the newer features in Android 1.6 and 2.0. Let us know in the android-developers Google Group if you have any questions about these new samples or about the new Resources tab.

Thanks for tuning in, and 'til next time, happy coding!

Come to Our Virtual Office Hours

Starting this week, we're going to be holding regular IRC office hours for Android app developers in the #android-dev channel on irc.freenode.net. Members of the Android team will be on hand to answer your technical questions. (Note that we will not be able to provide customer support for the phones themselves.)

We've arranged our office hours to accommodate as many different schedules as possible, for folks around the world. We will initially hold two sessions each week:

• 12/15/09 Tuesday, 9 a.m. to 10 a.m. PST
• 12/17/09, Thursday 5 p.m. to 6 p.m. PST
• 12/22/09, Tuesday 9 a.m. to 10 a.m. PST
• 01/06/10 Wednesday 9 a.m. to 10 a.m. PST
• 01/07/10 Thursday 5 p.m. to 6 p.m. PST

Check Wikipedia for a helpful list of IRC clients. Alternatively, you could use a web interface such as the one at freenode.net. We will try to answer as many as we can get through in the hour.

We hope to see you there!

Optimize your layouts

Writing user interface layouts for Android applications is easy, but it can sometimes be difficult to optimize them. Most often, heavy modifications made to existing XML layouts, like shuffling views around or changing the type of a container, lead to inefficiencies that go unnoticed.

Starting with the SDK Tools Revision 3 you can use a tool called layoutopt to automatically detect common problems. This tool is currently only available from the command line and its use is very simple - just open a terminal and launch the layoutopt command with a list of directories or XML files to analyze:

$ layoutopt samples/
samples/compound.xml
  7:23 The root-level <FrameLayout/> can be replaced with <merge/>
  11:21 This LinearLayout layout or its FrameLayout parent is useless samples/simple.xml
  7:7 The root-level <FrameLayout/> can be replaced with <merge/>
samples/too_deep.xml
  -1:-1 This layout has too many nested layouts: 13 levels, it should have <= 10!
  20:81 This LinearLayout layout or its LinearLayout parent is useless
  24:79 This LinearLayout layout or its LinearLayout parent is useless
  28:77 This LinearLayout layout or its LinearLayout parent is useless
  32:75 This LinearLayout layout or its LinearLayout parent is useless
  36:73 This LinearLayout layout or its LinearLayout parent is useless
  40:71 This LinearLayout layout or its LinearLayout parent is useless
  44:69 This LinearLayout layout or its LinearLayout parent is useless
  48:67 This LinearLayout layout or its LinearLayout parent is useless
  52:65 This LinearLayout layout or its LinearLayout parent is useless
  56:63 This LinearLayout layout or its LinearLayout parent is useless
samples/too_many.xml
  7:413 The root-level <FrameLayout/> can be replaced with <merge/>
  -1:-1 This layout has too many views: 81 views, it should have <= 80! samples/useless.xml
  7:19 The root-level <FrameLayout/> can be replaced with <merge/>
  11:17 This LinearLayout layout or its FrameLayout parent is useless

For each analyzed file, the tool will indicate the line numbers of each tag that could potentially be optimized. In some cases, layoutopt will also offer a possible solution.

The current version of layoutopt contains a dozen rules used to analyze your layout files and future versions will contain more. Future plans for this tool also include the ability to create and use your own analysis rules, to automatically modify the layouts with optimized XML, and to use it from within Eclipse and/or a standalone user interface.

Windows users: to start layoutopt, open the file called layoutopt.bat in the tools directory of the SDK and on the last line, replace %jarpath% with -jar %jarpath%.

Android SDK Updates

Today we are releasing updates to multiple components of the Android SDK:

• Android 2.0.1, revision 1
• Android 1.6, revision 2
• SDK Tools, revision 4

Android 2.0.1 is a minor update to Android 2.0. This update includes several bug fixes and behavior changes, such as application resource selection based on API level and changes to the value of some Bluetooth-related constants. For more detailed information, please see the Android 2.0.1 release notes.

To differentiate its behavior from Android 2.0, the API level of Android 2.0.1 is 6. All Android 2.0 devices will be updated to 2.0.1 before the end of the year, so developers will no longer need to support Android 2.0 at that time. Of course, developers of applications affected by the behavior changes should start compiling and testing their apps immediately.

We are also providing an update to the Android 1.6 SDK component. Revision 2 includes fixes to the compatibility mode for applications that don't support multiple screen sizes, as well as SDK fixes. Please see the Android 1.6, revision 2 release notes for the full list of changes.

Finally, we are also releasing an update to the SDK Tools, now in revision 4. This is a minor update with mostly bug fixes in the SDK Manager. A new version of the Eclipse plug-in that embeds those fixes is also available. For complete details, please see the SDK Tools, revision 4 and ADT 0.9.5 release notes.

One more thing: you can now follow us on twitter @AndroidDev.