Error launching Android NDK app

Question

I've written a NativeActivity that's crashing on launch because (my theory...) I'm doing something wrong naming the shared library or the module or something in AndroidManifest.xml. Below is the output of LogCat when my app is launched, along with the contents of my manifest file.

Any ideas where I've gone wrong in setting this up?

Thanks, ALF

===================MANIFEST=============================================

<?xml version="1.0" encoding="utf-8"?>
<!-- BEGIN_INCLUDE(manifest) -->
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.Mythica.SpiderGame"
        android:versionCode="1"
        android:versionName="1.0">

    <!-- This is the platform API where NativeActivity was introduced. -->
    <uses-sdk android:minSdkVersion="12" />

    <!-- This .apk has no Java code itself, so set hasCode to false. -->
    <application android:label="@string/app_name" android:hasCode="false">

        <!-- Our activity is the built-in NativeActivity framework class.
             This will take care of integrating with our NDK code. -->
        <activity android:name="android.app.NativeActivity"
                android:label="@string/app_name"
                android:configChanges="orientation|keyboardHidden">
            <!-- Tell NativeActivity the name of or .so -->
            <meta-data android:name="android.app.lib_name"
                    android:value="SpiderGame" />
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>
<!-- END_INCLUDE(manifest) -->

===================LOGCAT OUTPUT=============================================

07-31 23:13:11.770: WARN/dalvikvm(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: ERROR/AndroidRuntime(1384): 07-31 23:13:11.780: WARN/ActivityManager(288): 07-31 23:13:11.800: ERROR/android.os.Debug(288): threadid=1: thread exiting with uncaught exception (group=0x4016d760) FATAL EXCEPTION: main java.lang.RuntimeException: Unable to start activity ComponentInfo{com.Mythica.SpiderGame/android.app.NativeActivity}: java.lang.IllegalArgumentException: Unable to load native library: /data/data/com.Mythica.SpiderGame/lib/libSpiderGame.so at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1751) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1767) at android.app.ActivityThread.access$1500(ActivityThread.java:122) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1005) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:132) at android.app.ActivityThread.main(ActivityThread.java:4028) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:491) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:844) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.IllegalArgumentException: Unable to load native library: /data/data/com.Mythica.SpiderGame/lib/libSpiderGame.so at android.app.NativeActivity.onCreate(NativeActivity.java:199) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1048) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1715) ... 11 more Force finishing activity com.Mythica.SpiderGame/android.app.NativeActivity Dumpstate > /data/log/dumpstate_app_error

where is your .so ? Does your device support the NativeActivity ? — qrtt1, Aug 03 '11 at 01:28
I thought my .so was built into the .apk as a dependency, but that assumption must be invalid. The device supports NativeActivity. — ALF, Aug 06 '11 at 13:16

score 0 · Answer 1 · answered Aug 06 '11 at 13:15

The solution to my problem turned out to be building my game library as a static object rather than a shared one. MyApp references MyLibrary.so and I guess that shared library has to be copied onto the device manually before runtime, though I haven't tested that theory by doing so since static linking is doing the job.

If I'm correct, the invalid assumption was thinking any shared libraries of my own would be built into my .apk just like NativeActivity was built-in.

score 0 · Answer 2 · answered Aug 11 '11 at 20:05

You should read docs/PREBUILTS.html in the NDK. You can add a section looking like this to your Android.mk file:

#
# Include prebuilt shared library
#
include $(CLEAR_VARS)
LOCAL_MODULE := MyLibrary-prebuilt
LOCAL_SRC_FILES := relative/path/to/MyLibrary.so
LOCAL_EXPORT_C_INCLUDES := relative/path/to/includes
include $(PREBUILT_SHARED_LIBRARY)

and then just before you call BUILD_SHARED_LIBRARY at the end of your Android.mk, you put this:

LOCAL_SHARED_LIBRARIES := MyLibrary-prebuilt

This is assuming you have somehow managed to cross-compile your library for ARM outside of the ndk build system. If you want to build your shared library from within ndk-build, you do it the same way you build the .so for your native activity.

Error launching Android NDK app

2 Answers2