Android NDK 之 Hello World

#include <jni.h>
#include <string.h>
#include <stdio.h>


JNIEXPORT jstring JNICALL
Java_com_renhui_mplayer_MainActivity_displayHelloWorld(JNIEnv *env, jobject obj)
{
    return (*env)->NewStringUTF(env, "11111");
}

#定义本地路径变量 LOCAL_PATH
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := native-lib
LOCAL_SRC_FILES := native-lib.c
include $(BUILD_SHARED_LIBRARY)

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    // Example of a call to a native method
    TextView tv = (TextView) findViewById(R.id.sample_text);
    tv.setText(displayHelloWorld());
    }

    /**
     * A native method that is implemented by the ‘native-lib‘ native library,
     * which is packaged with this application.
     */
    public native String displayHelloWorld();

    // Used to load the ‘native-lib‘ library on application startup.
    static {
        System.loadLibrary("native-lib");
    }