Android VOIP应用程序无法访问互联网

Question

我需要在两个Android设备之间开发VOIP应用程序.
据我所知,有一个用于此目的的SIP协议,但它需要注册到SIP服务器并访问互联网以进行SIP信令.
有没有办法在没有互联网接入的情况下在Android中创建VOIP应用程序？

Answer 1

当然可以！为什么您需要互联网？只要您都连接到同一网络就可以了！以下是适用的应用程序的Java和xml。

在启动时，它将为您提供您自己的本地端口，例如“ 52022” ..每次都是随机的，不幸的是这无济于事。然后，我们输入另一部电话的IP地址和随机生成的端口号，然后按connect。它们的作用完全相同，万事通！该测试应用程序显然需要您在附近交换端口号，但是在我正确的应用程序中，我可以轻松地在连接之前请求每个端口号。希望这可以帮助！

public class MainActivity extends Activity {

AudioGroup m_AudioGroup;
AudioStream m_AudioStream;

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

    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
      StrictMode.setThreadPolicy(policy);
      try {   
          AudioManager audio =  (AudioManager) getSystemService(Context.AUDIO_SERVICE); 
          audio.setMode(AudioManager.MODE_IN_COMMUNICATION);
          m_AudioGroup = new AudioGroup();
          m_AudioGroup.setMode(AudioGroup.MODE_NORMAL);
          m_AudioStream = new AudioStream(InetAddress.getByAddress(getLocalIPAddress ()));
          int localPort = m_AudioStream.getLocalPort();
          m_AudioStream.setCodec(AudioCodec.PCMU);
          m_AudioStream.setMode(RtpStream.MODE_NORMAL);

          ((TextView)findViewById(R.id.lblLocalPort)).setText(String.valueOf(localPort));

          ((Button) findViewById(R.id.button1)).setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                String remoteAddress = ((EditText)findViewById(R.id.editText2)).getText().toString();
                String remotePort = ((EditText)findViewById(R.id.editText1)).getText().toString();

                  try {
                    m_AudioStream.associate(InetAddress.getByName(remoteAddress), Integer.parseInt(remotePort));
                } catch (NumberFormatException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (UnknownHostException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                  m_AudioStream.join(m_AudioGroup);
            }
        });

          ((Button) findViewById(R.id.button2)).setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v) {
                      m_AudioStream.release();
                }
            });

      } catch (Exception e) {
       Log.e("----------------------", e.toString());
       e.printStackTrace();
      }
}

public static byte[] getLocalIPAddress () {
    byte ip[]=null;
       try {
           for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {
               NetworkInterface intf = en.nextElement();
               for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {
                   InetAddress inetAddress = enumIpAddr.nextElement();
                   if (!inetAddress.isLoopbackAddress()) {
                    ip= inetAddress.getAddress();
                   }
               }
           }
       } catch (SocketException ex) {
           Log.i("SocketException ", ex.toString());
       }
       return ip;
    }
}

布局文件：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/LinearLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/lblLocalPort"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/localPort" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:ems="10"
        android:hint="@string/iPHint"
        android:inputType="phone" />

    <EditText
        android:id="@+id/editText1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:ems="10"
        android:hint="@string/portHint"
        android:inputType="number" >

        <requestFocus />
    </EditText>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" 
        android:layout_marginTop="20dp">

        <Button
            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/connect" />

        <Button
            android:id="@+id/button2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/Disconnect" />
    </LinearLayout>
</LinearLayout>

编辑： IP地址方法停止在API 22，使用下面的代码：

private byte[] getLocalIPAddress() {   
    byte[] bytes = null;

    try {
        // get the string ip
        WifiManager wm = (WifiManager) getSystemService(WIFI_SERVICE);
        String ip = Formatter.formatIpAddress(wm.getConnectionInfo().getIpAddress());

        // convert to bytes
        InetAddress inetAddress = null;
        try {
            inetAddress = InetAddress.getByName(ip);
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }

        bytes = new byte[0];
        if (inetAddress != null) {
            bytes = inetAddress.getAddress();
        }

    } catch (Exception e) {
        e.printStackTrace();
        Toast.makeText(this, R.string.phone_voip_incompatible, Toast.LENGTH_SHORT).show();
    }

    return bytes;
}