Tag Archives: mobile

How to Fix EXC_BAD_ACCESS (SIGSEGV) in HelloAndroid

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DroidWhen trying to build the Android Hello World tutorial in Eclipse I ran into an issue where the application would just crash when I tried to run it:

[2010-05-04 01:53:46 - HelloAndroid] ------------------------------
[2010-05-04 01:53:46 - HelloAndroid] Android Launch!
[2010-05-04 01:53:46 - HelloAndroid] adb is running normally.
[2010-05-04 01:53:46 - HelloAndroid] Performing com.example.helloandroid.HelloAndroid activity launch
[2010-05-04 01:53:46 - HelloAndroid] Automatic Target Mode: launching new emulator with compatible AVD 'myAVD'
[2010-05-04 01:53:46 - HelloAndroid] Launching a new emulator with Virtual Device 'myAVD'
[2010-05-04 01:53:58 - HelloAndroid] New emulator found: emulator-5554
[2010-05-04 01:53:58 - HelloAndroid] Waiting for HOME ('android.process.acore') to be launched...
[2010-05-04 01:53:59 - Emulator] 2010-05-04 01:53:59.501 emulator[10398:903] Warning once: This application, or a library it uses, is using NSQuickDrawView, which has been deprecated. Apps should cease use of QuickDraw and move to Quartz.
[2010-05-04 01:54:23 - HelloAndroid] emulator-5554 disconnected! Cancelling 'com.example.helloandroid.HelloAndroid activity launch'!

The crash report was identifying the problem as a segfault:

Process:         emulator [10472]
Path:            /Applications/android-sdk-mac_86/tools/emulator
Identifier:      emulator
Version:         ??? (???)
Code Type:       X86 (Native)
Parent Process:  eclipse [10468]

Date/Time:       2010-05-04 02:25:41.153 -0500
OS Version:      Mac OS X 10.6.3 (10D573)
Report Version:  6

Interval Since Last Report:          2558914 sec
Crashes Since Last Report:           4
Per-App Crashes Since Last Report:   2
Anonymous UUID:                      C5F178C1-5290-4CA9-AD6E-E9C4F5582754

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x000000001fd2f000
Crashed Thread:  3

The explanation

As best I could tell a snapshot of my AVD was saved while the previous version of HelloAndroid was running. And so when I went to run the new version of HelloAndroid (after making some code changes) the new package was copied over and then the emulator was restored. At this point it was in a corrupt state where the old version was still in memory but the new version existed in local storage. This may or may not be exactly what was happening, but it appeared to be what was causing the app to crash.

The fix

For me, I simply turned snapshots off on my AVD. To do that in Eclipse you can just follow this menu/button options:
Window -> AVD Manager -> [select your avd] -> Click Edit -> Uncheck “Enabled” next to Snapshots

If this doesn’t work you can also delete the AVD and create a new one with the same settings but with snapshots disabled.

If you’re still running into trouble, check out this thread over at StackOverflow. It didn’t solve my problems, but your mileage may vary. :)

Happy Android Coding!

How to Fix the Android NetworkOnMainThreadException

Posted on by • Posted in Android, Mobile • Tagged , , , , , , , , • 2 Comments

DroidIf you’re trying to communicate with a web service or scrape any data from the web in your Android application, you might run into an exception like this:

E/AndroidRuntime(673): java.lang.RuntimeException: Unable to start activity
ComponentInfo{com.example.helloandroid/com.example.helloandroid.HelloAndroidActivity}: android.os.NetworkOnMainThreadException

From Google’s documentation:

The exception that is thrown when an application attempts to perform a networking operation on its main thread.

This is only thrown for applications targeting the Honeycomb SDK or higher. Applications targeting earlier SDK versions are allowed to do networking on their main event loop threads, but it’s heavily discouraged.

The fix

The problem here is simply that you need to make your web service calls (or what-have-you) on a separate thread. So, quite simply, you’ll need to look into how to do threading with Android. Unfortunately this can be a bit of a pain because you need to make your service calls on a separate thread, but you need to update the UI on the main thread. Normally this would require passing data between the threads, which involves handlers or other complexities. Luckily the Android platform provides the Async Task to handle this, which alleviates some of this complexity and may help you avoid some clutter in your code.

Useful documentation to migrate your network calls to threads (or Android’s Async Task)

Painless Threading (from the Android Developer docs)
Async Task (from the Android Developer docs)
Android Threads, Handlers and AsyncTask – Tutorial
Designing for Responsiveness (from the Android Developer docs)

Good luck!

Google Plus for iPhone Released!

Posted on by • Posted in Mobile, Social • Tagged , , , , , , , , , , , , , , , , , , • Leave a comment

iPhoneiPhone users: your time has arrived! The Google+ app is now available in the app store! If you’re mobile browsing right now, you can click here to go straight to the download page. This makes the iPhone the second mobile device capable of running the G+ app, behind Google’s very own Android. The news was first leaked by Google employee Vic Gundotra and the first screenshots are available below.

Google Plus on iPhone 1Google Plus on iPhone 2

The features available for iPhone match those available for Android devices and include the group messaging Huddle capability. For a closer look at what the mobile app can do, take a look at the video below.