android ndk编程：socket

Question

我是ndk编程的新手，并尝试制作一个项目。我的项目的目的是构建一个客户端，我可以使用按钮的监听器来调用套接字编程的本机方法。并且，android中已经有服务器运行。当我构建它并将其导出为apk时，一切运行正常。但不幸的是，在我安装apk并尝试运行它之后。系统提示：不幸的是，NativeSocket已停止。以下是我的代码：NativeSocketActivity.java：

package gz.kaiwii;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class NativeSocketActivity extends Activity {
    /** Called when the activity is first created. */
    final Button button = (Button) findViewById(R.id.button1);
    /*static*/
    static{
        System.loadLibrary("NativeSocket");
    }
    /*native method stuff*/
    static native void start();
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        button.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                start();

            }
        });
    }
}

Android.门口:

LOCAL_PATH：= $（调用my-dir）

include $(CLEAR_VARS)

LOCAL_MODULE    := NativeSocket
### Add all source file names to be included in lib separated by a whitespace
LOCAL_SRC_FILES := NativeSocket.c

include $(BUILD_SHARED_LIBRARY)

NativeSocket.c：

#include <string.h>
#include <jni.h>
/*  Make the necessary includes and set up the variables.  */

#include <sys/types.h>
#include <sys/socket.h>
#include <stdio.h>
#include <sys/un.h>
#include <unistd.h>
#include <stdlib.h>

JNIEXPORT void JNICALL Java_gz_kaiwii_NativeSocketActivity_start
  (JNIEnv *env, jclass jclss)
{
    int sockfd;
    int len;
    struct sockaddr_un address;
    int result;
    char ch = 'A';

/*  Create a socket for the client.  */

    sockfd = socket(AF_UNIX, SOCK_STREAM, 0);

/*  Name the socket, as agreed with the server.  */

    address.sun_family = AF_UNIX;
    strcpy(address.sun_path, "server_socket");
    len = sizeof(address);

/*  Now connect our socket to the server's socket.  */

    result = connect(sockfd, (struct sockaddr *)&address, len);
/*
    if(result == -1) {
        perror("oops: client1");
        exit(1);
    }
    */

/*  We can now read/write via sockfd.  */

    write(sockfd, &ch, 1);
    read(sockfd, &ch, 1);
    /*
    printf("char from server = %c\n", ch);
    */
    close(sockfd);
}

Answer 1

我不确定在这种情况下是否需要这个 - 但你尝试将<uses-permission android:name="android.permission.INTERNET" />添加到你的AndroidManifest.xml文件中吗？

还有什么是确切的错误/异常以及崩溃时的调用堆栈？您可以在DDMS中或在命令行上使用adb logcat查看它。

另外 - 验证C函数的返回值并记录相应的错误消息。使用<android/log.h>。

Answer 2

您在setContentView ndk错误之后在onCreate方法中创建按钮引用永远不会强制关闭仅关闭vm。