SDL2 on android. FATAL EXCEPTION!

SDL Development
1

Hi,

I’m Chris, a graduate programmer who’s main language is C++.
I am working on a game which is currently PC only, I want to do something about that and have an android version.
And so I’m trying to get SDL2 working for android so I have been following this set-up guide: http://www.dinomage.com/2013/01/howto-sdl-on-android/

However, where it says I should have a nice working project… I do not. Instead I have a fatal exception.

Code:

08-20 11:48:46.684: D/dalvikvm(429): Trying to load lib /data/data/org.libsdl.app/lib/libSDL2.so 0x40512fb0
08-20 11:48:46.684: D/dalvikvm(429): Added shared lib /data/data/org.libsdl.app/lib/libSDL2.so 0x40512fb0
08-20 11:48:46.684: W/dalvikvm(429): Exception Ljava/lang/UnsatisfiedLinkError; thrown while initializing Lorg/libsdl/app/SDLActivity;
08-20 11:48:46.684: W/dalvikvm(429): Class init failed in newInstance call (Lorg/libsdl/app/SDLActivity;)
08-20 11:48:46.684: D/AndroidRuntime(429): Shutting down VM
08-20 11:48:46.684: W/dalvikvm(429): threadid=1: thread exiting with uncaught exception (group=0x40015560)
08-20 11:48:46.713: E/AndroidRuntime(429): FATAL EXCEPTION: main
08-20 11:48:46.713: E/AndroidRuntime(429): java.lang.ExceptionInInitializerError
08-20 11:48:46.713: E/AndroidRuntime(429): at java.lang.Class.newInstanceImpl(Native Method)
08-20 11:48:46.713: E/AndroidRuntime(429): at java.lang.Class.newInstance(Class.java:1409)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1561)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.os.Handler.dispatchMessage(Handler.java:99)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.os.Looper.loop(Looper.java:130)
08-20 11:48:46.713: E/AndroidRuntime(429): at android.app.ActivityThread.main(ActivityThread.java:3683)
08-20 11:48:46.713: E/AndroidRuntime(429): at java.lang.reflect.Method.invokeNative(Native Method)
08-20 11:48:46.713: E/AndroidRuntime(429): at java.lang.reflect.Method.invoke(Method.java:507)
08-20 11:48:46.713: E/AndroidRuntime(429): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
08-20 11:48:46.713: E/AndroidRuntime(429): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
08-20 11:48:46.713: E/AndroidRuntime(429): at dalvik.system.NativeStart.main(Native Method)
08-20 11:48:46.713: E/AndroidRuntime(429): Caused by: java.lang.UnsatisfiedLinkError: Couldn’t load main: findLibrary returned null
08-20 11:48:46.713: E/AndroidRuntime(429): at java.lang.Runtime.loadLibrary(Runtime.java:429)
08-20 11:48:46.713: E/AndroidRuntime(429): at java.lang.System.loadLibrary(System.java:554)
08-20 11:48:46.713: E/AndroidRuntime(429): at org.libsdl.app.SDLActivity.(SDLActivity.java:60)

Can anyone shed any light on this situation?

Thanks in advance.
Chris

2

That looks like it’s failing to find main.so, which is the shared library
that is created from your app code by ndk-build. Have you definitely run
ndk-build on your project?

Jonny DOn Tue, Aug 20, 2013 at 7:59 AM, Magusware wrote:

**
Hi,

I’m Chris, a graduate programmer who’s main language is C++.
I am working on a game which is currently PC only, I want to do something
about that and have an android version.
And so I’m trying to get SDL2 working for android so I have been following
this set-up guide: http://www.dinomage.com/2013/01/howto-sdl-on-android/

However, where it says I should have a nice working project… I do not.
Instead I have a fatal exception.

Code:

08-20 11:48:46.684: D/dalvikvm(429): Trying to load lib
/data/data/org.libsdl.app/lib/libSDL2.so 0x40512fb0
08-20 11:48:46.684: D/dalvikvm(429): Added shared lib
/data/data/org.libsdl.app/lib/libSDL2.so 0x40512fb0
08-20 11:48:46.684: W/dalvikvm(429): Exception
Ljava/lang/UnsatisfiedLinkError; thrown while initializing
Lorg/libsdl/app/SDLActivity;
08-20 11:48:46.684: W/dalvikvm(429): Class init failed in newInstance call
(Lorg/libsdl/app/SDLActivity;)
08-20 11:48:46.684: D/AndroidRuntime(429): Shutting down VM
08-20 11:48:46.684: W/dalvikvm(429): threadid=1: thread exiting with
uncaught exception (group=0x40015560)
08-20 11:48:46.713: E/AndroidRuntime(429): FATAL EXCEPTION: main
08-20 11:48:46.713: E/AndroidRuntime(429):
java.lang.ExceptionInInitializerError
08-20 11:48:46.713: E/AndroidRuntime(429): at
java.lang.Class.newInstanceImpl(Native Method)
08-20 11:48:46.713: E/AndroidRuntime(429): at
java.lang.Class.newInstance(Class.java:1409)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.app.Instrumentation.newActivity(Instrumentation.java:1021)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1561)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.app.ActivityThread.access$1500(ActivityThread.java:117)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.os.Handler.dispatchMessage(Handler.java:99)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.os.Looper.loop(Looper.java:130)
08-20 11:48:46.713: E/AndroidRuntime(429): at
android.app.ActivityThread.main(ActivityThread.java:3683)
08-20 11:48:46.713: E/AndroidRuntime(429): at
java.lang.reflect.Method.invokeNative(Native Method)
08-20 11:48:46.713: E/AndroidRuntime(429): at
java.lang.reflect.Method.invoke(Method.java:507)
08-20 11:48:46.713: E/AndroidRuntime(429): at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
08-20 11:48:46.713: E/AndroidRuntime(429): at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
08-20 11:48:46.713: E/AndroidRuntime(429): at
dalvik.system.NativeStart.main(Native Method)
08-20 11:48:46.713: E/AndroidRuntime(429): Caused by:
java.lang.UnsatisfiedLinkError: Couldn’t load main: findLibrary returned
null
08-20 11:48:46.713: E/AndroidRuntime(429): at
java.lang.Runtime.loadLibrary(Runtime.java:429)
08-20 11:48:46.713: E/AndroidRuntime(429): at
java.lang.System.loadLibrary(System.java:554)
08-20 11:48:46.713: E/AndroidRuntime(429): at
org.libsdl.app.SDLActivity.**(SDLActivity.java:60)

Can anyone shed any light on this situation?

Thanks in advance.
Chris

SDL mailing list
SDL at lists.libsdl.org
http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org

3

Yes I did. Took some fiddling around with to actually get it to run though.

4

When I was running ndk-build it went so fast I couldn’t see that it was actually erroring.

Code:
Install : libSDL2.so => libs/armeabi/libSDL2.so
"Compile thumb : main <= SDL_android_main.c
"Compile++ thumb : main <= main.cpp
SharedLibrary : libmain.so
F:/SDKs/Android/NDK/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64
/bin/…/lib/gcc/arm-linux-androideabi/4.6/…/…/…/…/arm-linux-androideabi/bin/
ld.exe: M:\Projects\Android\AndroidApp/obj/local/armeabi/objs/main/__/SDL/src/ma
in/android/SDL_android_main.o: in function Java_org_libsdl_app_SDLActivity_nativ
eInit:M:\Projects\Android\AndroidApp/jni/src/…/SDL/src/main/android/SDL_android
_main.c:30: error: undefined reference to 'SDL_main’
collect2: ld returned 1 exit status
make: *** [M:\Projects\Android\AndroidApp/obj/local/armeabi/libmain.so] Error 1

5

I think I solved the issue. I had to make my main.cpp look like this:

Code:
extern “C”
{
int SDL_main(int argc, char* argv[])
{
return 0;
}
}

what it used to be.

Code:
int SDL_main(int argc, char* argv[])
{
return 0;
}

Does this mean I’m going to have to wrap all my code in extern “C”?

[/code]

6

For anyone else who wants to know the answer to my previous question. The answer is no, only needed it on the entry point.