Android NDK

 

首先要把NDK進行下載安裝

新增專案選擇C++字眼的專案類型

於安卓模擬器運行

就會看到打印C++ 字串結果

預設的JNI C++程式碼

src/main/cpp/native-lib.cpp

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#include <jni.h> #include <string> extern "C" JNIEXPORT jstring JNICALL Java_com_example_ndktest_MainActivity_stringFromJNI( JNIEnv* env, jobject /* this */) { std::string hello = "Hello from C++"; return env->NewStringUTF(hello.c_str()); }

java程式進入點

src/main/java/com/example/ndktest/MainActivity.java

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package com.example.ndktest; import androidx.appcompat.app.AppCompatActivity; import android.os.Bundle; import android.widget.TextView; import com.example.ndktest.databinding.ActivityMainBinding; public class MainActivity extends AppCompatActivity { // Used to load the 'ndktest' library on application startup. static { System.loadLibrary("ndktest"); } private ActivityMainBinding binding; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); binding = ActivityMainBinding.inflate(getLayoutInflater()); setContentView(binding.getRoot()); // Example of a call to a native method TextView tv = binding.sampleText; tv.setText(stringFromJNI()); } /** * A native method that is implemented by the 'ndktest' native library, * which is packaged with this application. */ public native String stringFromJNI(); }