Friday, December 11, 2009

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!

Thursday, December 10, 2009

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%.

Thursday, December 3, 2009

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.