在Android NDK中使用两个共享库并支持RTTI和动态转型是可能的。下面是一个解决方案的代码示例:
首先,需要在Android.mk文件中添加相关的配置信息:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
# 配置第一个共享库
LOCAL_MODULE := first_lib
LOCAL_SRC_FILES := first_lib.cpp
LOCAL_CPP_FEATURES += exceptions rtti
# 添加其他需要的编译选项
include $(BUILD_SHARED_LIBRARY)
# 配置第二个共享库
include $(CLEAR_VARS)
LOCAL_MODULE := second_lib
LOCAL_SRC_FILES := second_lib.cpp
LOCAL_CPP_FEATURES += exceptions rtti
# 添加其他需要的编译选项
include $(BUILD_SHARED_LIBRARY)
接下来,需要确保在C++代码中正确使用RTTI和动态转型。下面是一个简单的示例:
first_lib.cpp:
#include
class Base {
public:
virtual void print() {
std::cout << "Base class" << std::endl;
}
};
class Derived : public Base {
public:
void print() override {
std::cout << "Derived class" << std::endl;
}
};
extern "C" {
JNIEXPORT void JNICALL Java_com_example_myapplication_MainActivity_testDynamicCast(JNIEnv* env, jobject obj) {
Base* base = new Derived();
Derived* derived = dynamic_cast(base);
if (derived) {
derived->print();
} else {
std::cout << "Dynamic cast failed" << std::endl;
}
delete base;
}
}
second_lib.cpp:
#include
class SecondLibClass {
public:
void print() {
std::cout << "SecondLibClass" << std::endl;
}
};
extern "C" {
JNIEXPORT void JNICALL Java_com_example_myapplication_MainActivity_testRtti(JNIEnv* env, jobject obj) {
SecondLibClass secondLibObj;
const std::type_info& typeInfo = typeid(secondLibObj);
std::cout << "Type: " << typeInfo.name() << std::endl;
}
}
最后,在Java代码中调用这些函数:
public class MainActivity extends AppCompatActivity {
static {
System.loadLibrary("first_lib");
System.loadLibrary("second_lib");
}
public native void testDynamicCast();
public native void testRtti();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
testDynamicCast();
testRtti();
}
}
这样,就可以在Android NDK中使用两个共享库并支持RTTI和动态转型了。请根据实际需求进行修改和调整。