从java层向jni中传递GLSurfaceView的方法

Posted 2020-10-23 恒

从java朝jni中传递各种数据，是在android开发中经常需要面对的事情。对于一些典型的数据类型，网上已经有很多文章介绍，这里列出一些数据类型：

 

对于GLSurfaceView，则使用：Landroid/opengl/GLSurfaceView;

我的程序分为三层，App层，SDK层和capture层，其中capture层是采用c++调用java接口实现。

下面将详细流程叙述如下：

1.在抽象java类中声明native接口

public class ConfMgr {

static {

try {

System.loadLibrary("confmgr");

}catch (Throwable e){

Log.e("conf", "load so error："+e.getMessage());

}

}

public static native void InitAndroidVM(Context context);

public static native void UninitAndroidVM();

public static native void SetPreviewWnd(SurfaceView glview);

}

2.用javah命令生成头文件

JNIEXPORT void JNICALL Java_com_jni_conf_ConfMgr_SetPreviewWnd(JNIEnv *env, jclass instance,jobject glview);

3.实现函数接口，声明接口SetCamPreviewWnd

void WINAPI SelectCameraFace(BOOL bFrontFace);

JNIEXPORT void JNICALL Java_com_jni_conf_ConfMgr_SetPreviewWnd(JNIEnv *env, jclass instance,jobject glview)

{

SetCamPreviewWnd(glview);

}

4.在SDK库文件中实现和声明接口SetCamPreviewWnd

UTIL_EXPORT void WINAPI SetCamPreviewWnd(jobject glview);

extern "C" void WINAPI SetCamPreviewWnd(jobject glview)

{

TRACE_INFO2("vmgr::SetCamPreview");

SetLocalPreview(glview);

}

5.在Campture库文件中声明和实现SetLocalPreview接口

extern "C" int32_t WINAPI SetLocalPreview(jobject glview);

class androidcapturedelegate {

public:

static androidcapturedelegate* Create();

static void Destroy(androidcapturedelegate *pDelete);

 

androidcapturedelegate(const int32_t id);

androidcapturedelegate();

virtual int32_t Init();

void InitCapture(int iWidth, int iHeight, int iFps, int iBitrate);

static void SetLocalCamPreview(jobject glview);

void SetCamPreview(jobject glview);

static androidcapturedelegate *g_pAndCapDel;

protected:

virtual ~androidcapturedelegate();

jobject _jCapturer; // Global ref to Java VideoCaptureAndroid object.

};

void androidcapturedelegate::SetLocalCamPreview(jobject glview)

{

if(androidcapturedelegate::g_pAndCapDel != NULL)

{

TRACE_INFO2("androidcapturedelegate::SetLocalCamPreview, enter");

g_pAndCapDel->SetCamPreview(glview);

}

}

void androidcapturedelegate::SetCamPreview(jobject glview)

{

TRACE_INFO2("androidcapturedelegate::SetCamPreview, enter");

 

AttachThreadScoped ats(g_jvm);

JNIEnv* env = ats.env();

jmethodID jmethodID =

env->GetMethodID(g_java_capturer_class, "setLocalPreview", "(Landroid/opengl/GLSurfaceView;)V");

assert(jmethodID);

env->CallVoidMethod(_jCapturer, jmethodID,glview);

}

6.在java文件中实现setLocalPreview接口

public class VideoCaptureAndroid implements GLSurfaceView.Renderer {

private GLSurfaceView mLocalPreview = null;

public VideoCaptureAndroid(long native_capturer) {

}

public void setLocalPreview(GLSurfaceView localPreview) {

mLocalPreview = (GLSurfaceView) localPreview;

mLocalPreview.setEGLContextClientVersion(2);

mLocalPreview.setRenderer(mSelf);

mLocalPreview.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);

if(!mEnableHWCODEC) {

mLocalPreview.getHolder().setFixedSize(640, 480);

}

}

}