Using JNI to call C lib on android platform

by Dianne Hackborn » Wed, 04 Feb 2009 12:09:19 GMT


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 That API is part of the SDK, but native code is not a part of the SDK, so it
probably won't do you much good.







-- 
Dianne Hackborn
Android framework engineer
hack...@android.com

Note: please don't send private questions to me, as I don't have time to
provide private support.  All such questions should be posted on public
forums, where I and others can see and answer them.

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Using JNI to call C lib on android platform

by Jerry Yang » Wed, 04 Feb 2009 12:35:29 GMT


 Hi, Dianne

I also see some declaration that says the native code is not supported
in current SDK.

 

I am a little bit confused.

So is this API can work for loading a C written library? That means the
android java platform can use the function implied in the library( .so
cross-compiled by arm based GCC), is that right?

Maybe my conception is not correct, but what is the exact meaning of
"Native code support"? is it means the JNI or anything else?

 

Thanks

With best wishes

Jerry 

 

From: android-developers@googlegroups.com
[mailto:android-develop...@googlegroups.com] On Behalf Of Dianne
Hackborn
Sent: Wednesday, February 04, 2009 12:09 PM
To: android-developers@googlegroups.com
Subject: [android-developers] Re: [android-developers]Using JNI to call
C lib on android platform

 

That API is part of the SDK, but native code is not a part of the SDK,
so it probably won't do you much good.

On Tue, Feb 3, 2009 at 7:41 PM, Jerry Yang <jer...@intertrust.com>



Hi, Dianne

I find an api with the name "java.lang.System.loadLibrary
< http://code.google.com/android/reference/java/lang/System.html #loadLibr
ary%28java.lang.String%29> "

Is this api not supported in Android SDK now?

Thanks

With best wishes

Jerry

 

From: android-developers@googlegroups.com
[mailto:android-develop...@googlegroups.com] On Behalf Of Dianne
Hackborn
Sent: Wednesday, February 04, 2009 11:25 AM
To: android-developers@googlegroups.com
Subject: [android-developers] Re: [android-developers]Using JNI to call
C lib on android platform

 

Sorry, native code is not currently supported in the SDK.

On Tue, Feb 3, 2009 at 6:27 PM, Jerry Yang <jer...@intertrust.com>



Hi, all

Does anyone have any information about using the external C written lib?

I have a C lib(no user interface, can be compiled like dll or lib) that
need to be used in the app, but I cannot find any document in android
SDK about how to use the external lib.

 

My idea is: I should cross-compile the lib with arm based detain GCC and
use the interface to Android app. Any one has any document or example
about this?

Appreciate for your help!

 

With best wishes

Jerry Yang

 

 

 

 




-- 

Dianne Hackborn
Android framework engineer
hack...@android.com

Note: please don't send private questions to me, as I don't have time to
provide private support.  All such questions should be posted on public
forums, where I and others can see and answer them.



 

 




-- 
Dianne Hackborn
Android framework engineer
hack...@android.com

Note: please don't send private questions to me, as I don't have time to
provide private support.  All such questions should be posted on public
forums, where I and others can see and answer them.




--~--~---------~--~----~------------~-------~--~----~


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Using JNI to call C lib on android platform

by Dianne Hackborn » Wed, 04 Feb 2009 12:56:01 GMT


 t means that the SDK does not include support for native ARM code.
Figuring out tricks to use it is just like working around the SDK to use
some other unsupported API: you will most likely break at some point in the
future when your users receive an OTA update that changes the API you are
using. In this case, the API is the entire set of APIs for native code: the
calling conventions, posix and c library, etc.

Sorry but that is all I have time to post on this topic. You can do a
search on the group to find numerous other discussions on it.

On Tue, Feb 3, 2009 at 8:35 PM, Jerry Yang <jer...@intertrust.com> wrote:



--
Dianne Hackborn
Android framework engineer
hack...@android.com

Note: please don't send private questions to me, as I don't have time to
provide private support. All such questions should be posted on public
forums, where I and others can see and answer them.

--~--~---------~--~----~------------~-------~--~----~



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