You can pass any java object to native code and manipulate it via JNI. Doug
On Dec 15, 1:46 am, JC <[email protected]> wrote: > Hello all, > > I understood that why it is not allowed. > > So if one have achieve same, what is another method for > implementation? > > Can we pass AudioTrack object created in JAVA to native and do > audiotrack.write in C ? > > Thanks in advance, > Jay > > On Oct 27, 4:59 am, HamdiHamZ <[email protected]> wrote: > > > > > > > > > Ok, I get your point > > > Thanks for your help > > > On Oct 26, 5:56 pm, David Turner <[email protected]> wrote: > > > > On Wed, Oct 26, 2011 at 1:19 AM, HamdiHamZ <[email protected]> wrote: > > > > Hi Dianne and thank you for your reply, > > > > > Sorry, I can't get your point, do you mean that we can't use C++ > > > > at all with the NDK? So why we can see cpp classes in the android > > > > sources? is it only to build libs and after that libs should be used > > > > from Java? > > > > No, it simply means you can't write code that tries to access internal C++ > > > classes from the platform because these are not exposed by the NDK. > > > > In other words, you're trying to access functions that are used by the > > > system, but not available to applications because they can (and will be) > > > be > > > modified or removed at will between platform releases, or simply in custom > > > ROMs. > > > > > Regards, > > > > > On Oct 25, 8:38 pm, Dianne Hackborn <[email protected]> wrote: > > > > > This is not part of the NDK. *NO* C++ classes are part of the NDK. > > > > > > Even if you manage to get this to work, you are using private > > > > implementation > > > > > details of the platform, and I can guarantee you that your app will > > > > > break > > > > > all over the place on different devices. > > > > > > On Tue, Oct 25, 2011 at 1:36 AM, HamdiHamZ <[email protected]> > > > > wrote: > > > > > > Hi folks, > > > > > > > I ma trying to write a media player for Android 2.2. I am using > > > > > > NDK_rb6 to build my JNI library written i C/C++ (under Ubuntu > > > > > > 11.04)... Actually, I faced a lot of problems of linking and > > > > > > dependencies, I resolved a lot of the and I am stuck with this one: > > > > > > > ~/dev/workspace/MyApp/jni/android-out.cpp:95: undefined reference to > > > > > > `android::AudioTrack::set(int, unsigned int, int, int, int, unsigned > > > > > > int, void (*)(int, void*, void*), void*, int, > > > > > > android::sp<android::IMemory> const&, bool, int)' > > > > > > collect2: ld returned 1 exit status > > > > > > > However, I found its definition in $(ANDROID_SRC)/frameworks/base/ > > > > > > media/libmedia/AudioTrack.cpp: > > > > > > > status_tAudioTrack::set( > > > > > > int streamType, > > > > > > uint32_t sampleRate, > > > > > > int format, > > > > > > int channels, > > > > > > int frameCount, > > > > > > uint32_t flags, > > > > > > callback_t cbf, > > > > > > void* user, > > > > > > int notificationFrames, > > > > > > const sp<IMemory>& sharedBuffer, > > > > > > bool threadCanCallJava, > > > > > > int sessionId) > > > > > > { > > > > > > ... > > > > > > } > > > > > > > and in the header that I included (media/audioTrack.h): > > > > > > > /* Initialize an uninitializedAudioTrack. > > > > > > * Returned status (from utils/Errors.h) can be: > > > > > > * - NO_ERROR: successful intialization > > > > > > * - INVALID_OPERATION:AudioTrackis already intitialized > > > > > > * - BAD_VALUE: invalid parameter (channels, format, > > > > > > sampleRate...) > > > > > > * - NO_INIT: audio server or audio hardware not initialized > > > > > > * */ > > > > > > status_t set(int streamType =-1, > > > > > > uint32_t sampleRate = 0, > > > > > > int format = 0, > > > > > > int channels = 0, > > > > > > int frameCount = 0, > > > > > > uint32_t flags = 0, > > > > > > callback_t cbf = 0, > > > > > > void* user = 0, > > > > > > int notificationFrames = 0, > > > > > > const sp<IMemory>& sharedBuffer = 0, > > > > > > bool threadCanCallJava = false, > > > > > > int sessionId = 0); > > > > > > > and I am using it this way: > > > > > > > status = track->set(AudioSystem::MUSIC, > > > > > > audec->samplerate, > > > > > > AudioSystem::PCM_16_BIT, > > > > > > (audec->channels == 1) ? > > > > > > AudioSystem::CHANNEL_OUT_MONO : AudioSystem::CHANNEL_OUT_STEREO, > > > > > > 0, // frameCount > > > > > > 0, // flags > > > > > > audioCallback, > > > > > > audec, // user when callback > > > > > > 0, // notificationFrames > > > > > > 0, // shared buffer > > > > > > 0); > > > > > > > So I am not able to see where am I wrong? > > > > > > > -- > > > > > > You received this message because you are subscribed to the Google > > > > > > Groups "Android Developers" group. > > > > > > To post to this group, send email to > > > > [email protected] > > > > > > To unsubscribe from this group, send email to > > > > > > [email protected] > > > > > > For more options, visit this group at > > > > > >http://groups.google.com/group/android-developers?hl=en > > > > > > -- > > > > > Dianne Hackborn > > > > > Android framework engineer > > > > > [email protected] > > > > > > Note: please don't send private questions to me, as I don't have time > > > > > to > > > > > provide private support, and so won't reply to such e-mails. All such > > > > > questions should be posted on public forums, where I and others can > > > > > see > > > > and > > > > > answer them. > > > > > -- > > > > You received this message because you are subscribed to the Google > > > > Groups "Android Developers" group. > > > > To post to this group, send email to [email protected] > > > > To unsubscribe from this group, send email to > > > > [email protected] > > > > For more options, visit this group at > > > >http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
