矢量不能JNI

Question

导入Java代码：

System.loadLibrary("twolib-second"); 

int z = add(1, 2); 

public native int add(int x, int y); 

first.cpp：

#ifdef __cplusplus extern "C" { 
#endif 


using namespace std; 


int first(int x, int y) { 
    return x*10 + y; } 

#ifdef __cplusplus } 
#endif 

second.c：

//THIS IS THE source of trouble :) 
//without the include of vector works just fine 
//but after adding the include for vector code can't be compiled 
#include <vector> 

#include <jni.h> 

jint 
Java_com_example_jniexample_MainActivity_add(JNIEnv* env, 
             jobject this, 
             jint  x, 
             jint  y) 
{ 
    return first(x, y); 
} 

Android.mk：

LOCAL_PATH:= $(call my-dir) 

# first lib, which will be built statically 
# 
include $(CLEAR_VARS) 

LOCAL_MODULE := libtwolib-first 
LOCAL_SRC_FILES := first.cpp 

include $(BUILD_STATIC_LIBRARY) 

# second lib, which will depend on and include the first one 
# 
include $(CLEAR_VARS) 

LOCAL_MODULE := libtwolib-second 
LOCAL_SRC_FILES := second.c 

LOCAL_STATIC_LIBRARIES := libtwolib-first 

include $(BUILD_SHARED_LIBRARY) 

我不断收到此错误：

from jni/second.c:20: /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_relops_cont.h:6:1: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_relops_cont.h:14:1: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_relops_cont.h:21:1: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_relops_cont.h:21:1: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_relops_cont.h:21:1: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_relops_cont.h:21:1: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_relops_cont.h:24:1: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token In file included from /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/vector:37:0, from jni/second.c:20: /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_vector.h:752:10: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token /home/username/dev/ndk/android-ndk-r9/sources/cxx-stl/stlport/stlport/stl/_vector.h:760:10: error: expected '=', ',', ';', 'asm' or 'attribute' before '<' token

在Application.mk

APP_STL := stlport_static

Answer 1

我怀疑你使用默认的C++运行时，它不支持标准库。

有关整个信息，请参阅ndk安装文件夹中的文件docs/CPLUSPLUS-SUPPORT.html。

为了能够使用（因此，包括无误差）vector，你需要在你Application.mk 可以使用strlport或gnustl以启用原生Android开发的标准库，通过添加类似定义APP_STL即：

APP_STL := gnustl_static 

另一个问题：您尝试包括在C文件vector，所以这是行不通的。