android开发

1. java native

package com.demo;

public class DemoNative {
    public static native void getData(String key);
    
    static{
        System.loadLibrary("demojni");
    }
}

2. Android.mk

LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

LOCAL_SRC_FILES := com_demo.DemoNamtive.cpp

LOCAL_C_INCLUDES += \
    $(JNI_H_INCLUDE)

LOCAL_SHARED_LIBRARIES := \
    libnativehelper \
    libcutils \
    libutils

LOCAL_MODULE:= libdemojni
LOCAL_MODULE_TAGS := optional
LOCAL_PRELINK_MODULE := false

include $(BUILD_SHARED_LIBRARY)    

3. com_demo.DemoNamtive.cpp

namespace android {

static void com_demo_DemoNative_getData(JNIEnv* env, jobject obj, jstring data)
{
    LOGD("get data: %s", data);
}

static JNINativeMethod gDemoNativeMethods[] =
{
        {"getData", "(Ljava/lang/String;)V", (void*)com_demo_DemoNative_getData}
};


int register_Native(JNIEnv* env)
{
      int res = jniRegisterNativeMethods(env, "com/demo/DemoNative",
              gDemoNativeMethods, NELEM(gDemoNativeMethods));
        LOG_FATAL_IF(res < 0, "Unable to register native methods.");

        return 0;
}

extern "C" jint JNI_OnLoad(JavaVM* vm, void* reserved)
{
    JNIEnv* env = NULL;
    jint result = -1;

    if (vm->GetEnv((void **)&env, JNI_VERSION_1_4)!= JNI_OK)
    {
        LOGE("GetEnv failed!");
        return result;
    }

    register_Native(env);

    return JNI_VERSION_1_4;
}
}  // namespace android

4. Android.mk

LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

LOCAL_MODULE_TAGS := optional

LOCAL_SRC_FILES := $(call all-subdir-java-files)

LOCAL_PACKAGE_NAME := DemoNative
LOCAL_CERTIFICATE := platform

LOCAL_REQUIRED_MODULES := libdemojni
LOCAL_JNI_SHARED_LIBRARIES := libdemojni
include $(BUILD_PACKAGE)
include $(call all-makefiles-under,$(LOCAL_PATH))

5. Copy to Androidsrc

6. mm

7. adb install out/target/product/generic/system/app/DemoNative.apk