android ndk when the program has two classes

Question

I have a problem when using ndk in Android

First, I have MainActivity class / A & B classes In native-lib.cpp, I implemented two functions which will be used in A / B classes as follows.

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extern "C"{
int Java_packagename_A_Afunc();
double Java_packagename_B_Bfunc();}

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Also, in both A and B classes, library is set and functions are declared as follows.

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class A:

static { System.loadLibrary("native-lib"); }
public native double A();

class B:

static { System.loadLibrary("native-lib"); }
public native double B();

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However, when I run this program, I abruptly stopped. Also, in native-lib.cpp, although I used the functions in two classes, following message is appeared when the cursor is positioned on the name of function.

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Function 'Java_packagename_A_Afunc' is never used

Function 'Java_packagename_B_Bfunc' is never used

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What's wrong in my program code?

_"I abruptly stopped"_ And what is the error you're getting in the logs? Also, why is `A` returning an `int` in your C++ code but declared as `double` in your Java code? — Michael, Nov 24 '16 at 18:21
Is it real C++ declarations, that you pass to compiler, or just some kind of pseudocode? — Sergio, Nov 25 '16 at 11:35
If you are using the native library from more than one class then define your native library calls and loading the library itself in a class of their own. — WLGfx, Nov 25 '16 at 11:43
Are you using the JNIEXPORT and JNICALL macros? You also need to have JNIEnv* and jobject parameters in your JNI functions. See this example: http://stackoverflow.com/questions/19422660/when-to-use-jniexport-and-jnicall-in-android-ndk — samgak, Nov 25 '16 at 21:57

android ndk when the program has two classes

0 Answers0