未调用Android P2P服务发现回调
作者：互联网
我对Android很新,我正在开发一个通过WIFI直接交换数据的应用程序,我想使用DNS服务发现而不是纯P2P发现来获取更多有用的信息,如设备“昵称”等.
到目前为止,我已经按照http://developer.android.com/training/connect-devices-wirelessly/index.html的教程进行了阅读并阅读了文档.
我的应用程序似乎成功注册了它的本地服务,并始终调用来自discoverServices的onSuccess回调,但是从未收到来自其他设备的txtServiceRecord(我正在使用2个设备).
这是我的完整代码：
package com.caballero.marco.dnssd_test;
import android.graphics.Color;
import android.net.wifi.p2p.WifiP2pDevice;
import android.net.wifi.p2p.WifiP2pManager;
import android.net.wifi.p2p.WifiP2pManager.Channel;
import android.net.wifi.p2p.WifiP2pManager.DnsSdTxtRecordListener;
import android.net.wifi.p2p.WifiP2pManager.DnsSdServiceResponseListener;
import android.net.wifi.p2p.nsd.WifiP2pDnsSdServiceInfo;
import android.net.wifi.p2p.WifiP2pManager.ActionListener;
import android.net.wifi.p2p.nsd.WifiP2pDnsSdServiceRequest;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.text.SpannableString;
import android.text.Spanned;
import android.text.style.ForegroundColorSpan;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.TextView;
import java.io.IOException;
import java.net.ServerSocket;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
public class MainActivity extends ActionBarActivity
{
public static String SERVICE_NAME = "_marcotest";
private int server_port = 0;
private WifiP2pManager mManager;
private Channel channel;
private ServerSocket serverSocket;
private TextView txtServiceStatus;
private Button btnDiscover;
final HashMap<String, String> buddies = new HashMap<String, String>();
private ArrayAdapter<String> adapter;
//private ActionListener serviceDiscoveryListener;
private WifiP2pDnsSdServiceRequest serviceRequest;
private DnsSdServiceResponseListener serviceResponseListener;
private DnsSdTxtRecordListener txtRecordListener;
private WifiP2pDnsSdServiceInfo serviceInfo;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/* Load controls */
txtServiceStatus = (TextView)findViewById(R.id.txtStatus);
btnDiscover = (Button)findViewById(R.id.btnDiscover);
btnDiscover.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startServiceDiscovery();
}
});
mManager = (WifiP2pManager)getSystemService(WIFI_P2P_SERVICE);
channel = mManager.initialize(this, getMainLooper(), null);
adapter = new ArrayAdapter<String>( this,
android.R.layout.simple_list_item_1,
new ArrayList<String>());
/* Initialize Socket Server */
try {
initializeSocketServer();
}
catch (IOException e)
{
e.printStackTrace();
}
startRegistration();
setupDiscoverServices();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private void startRegistration() {
// Create a string map containing information about your service.
Map record = new HashMap();
record.put("listenport", String.valueOf(server_port));
record.put("buddyname", "John Doe" + (int) (Math.random() * 1000));
record.put("available", "visible");
// Service information. Pass it an instance name, service type
// _protocol._transportlayer , and the map containing
// information other devices will want once they connect to this one.
serviceInfo = WifiP2pDnsSdServiceInfo.newInstance(SERVICE_NAME, "._tcp", record);
// Add the local service, sending the service info, network channel,
// and listener that will be used to indicate success or failure of
// the request.
mManager.addLocalService(channel, serviceInfo, new WifiP2pManager.ActionListener() {
@Override
public void onSuccess() {
// Command successful! Code isn't necessarily needed here,
// Unless you want to update the UI or add logging statements.
SpannableString text = new SpannableString("Online");
text.setSpan(new ForegroundColorSpan(Color.GREEN), 0, text.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
txtServiceStatus.setText(text);
Log.v("DnsSDTest", "Service added.");
}
@Override
public void onFailure(int arg0)
{
// Command failed. Check for P2P_UNSUPPORTED, ERROR, or BUSY
SpannableString text = new SpannableString("Offline");
text.setSpan(new ForegroundColorSpan(Color.RED), 0, text.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
txtServiceStatus.setText(text);
}
});
}
private void initializeSocketServer() throws IOException
{
serverSocket = new ServerSocket(0);
server_port = serverSocket.getLocalPort();
}
private void setupDiscoverServices()
{
txtRecordListener = new WifiP2pManager.DnsSdTxtRecordListener() {
@Override
public void onDnsSdTxtRecordAvailable(String fullDomainName, Map<String, String> txtRecordMap, WifiP2pDevice srcDevice)
{
Log.v("DnsSDTest", "DnsSdTxtRecord available -" + txtRecordMap.toString());
buddies.put(srcDevice.deviceAddress, txtRecordMap.get("buddyname"));
}
};
serviceResponseListener = new DnsSdServiceResponseListener() {
@Override
public void onDnsSdServiceAvailable(String instanceName, String registrationType, WifiP2pDevice srcDevice)
{
// Update the device name with the human-friendly version from
// the DnsTxtRecord, assuming one arrived.
srcDevice.deviceName = buddies
.containsKey(srcDevice.deviceAddress) ? buddies
.get(srcDevice.deviceAddress) : srcDevice.deviceName;
// Add to the custom adapter defined specifically for showing
// wifi devices.
adapter.add(srcDevice.toString());
adapter.notifyDataSetChanged();
Log.v("DnsSDTest", "onBonjourServiceAvailable " + instanceName);
}
};
mManager.setDnsSdResponseListeners(channel, serviceResponseListener, txtRecordListener);
Log.v("DnsSDTest", "Added DNS SD response listeners.");
}
private void startServiceDiscovery()
{
serviceRequest = WifiP2pDnsSdServiceRequest.newInstance();
mManager.addServiceRequest(channel, serviceRequest, new ActionListener() {
@Override
public void onSuccess() {
Log.v("DnsSDTest", "Service Request added successfully!");
}
@Override
public void onFailure(int reason) {
Log.v("DnsSDTest", "Failed to add service request!");
}
});
mManager.discoverServices(channel, new ActionListener() {
@Override
public void onSuccess() {
Log.v("DnsSDTest", "Service discovery successfull!");
}
@Override
public void onFailure(int reason) {
Log.v("DnsSDTest", "Service discovery failed :(");
}
});
}
@Override
protected void onPause()
{
super.onPause();
mManager.removeLocalService(channel, serviceInfo, new ActionListener() {
@Override
public void onSuccess() {
Log.v("DnsSDTest", "Removed service");
serviceInfo = null;
}
@Override
public void onFailure(int reason) {
Log.v("DnsSDTest", "Failed to remove service");
}
});
}
@Override
protected void onResume()
{
super.onResume();
if(serviceInfo == null)
{
startRegistration();
}
}
@Override
protected void onDestroy()
{
super.onDestroy();
try {
if(!serverSocket.isClosed())
serverSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
解决方法:
发现1：
只有在使用setupDiscoverServices()附加了两个侦听器(服务侦听器和txtrecord侦听器)之后,才需要为这些附加的列表器创建服务请求并启动发现.您可以随时手动创建服务请求并使用按钮触发发现服务,这很容易出错.在使用按钮调用startServiceDiscovery()之前,无法保证实际连接侦听器.
解决方案1：在设置DNS SD响应侦听器之后,即在mManager.setDnsSdResponseListeners()之后,尝试调用方法startServiceDiscovery(),而不是调用按钮单击Listener.
解决方案2：否则,我建议,移动你的
‘mManager.addServiceRequest(channel,serviceRequest,new ActionListener(){….}’
部分进入’setupDiscoverServices()’方法并尝试激活’mManager.addServiceRequest’的’onSuccess()’中的按钮(startServiceDiscovery()).通过这种方式,您可以实现连接侦听器,注册服务和启动发现(手动)之间的同步点
以下链接演示了WiFiDirect项目,其中对等体通过网络服务发现彼此连接以进行消息交换.这种方法的顺序要求网络服务发现为我工作.
https://github.com/Hariharan-Gandhi/WiFriends/blob/master/app/src/main/java/tud/cnlab/wifriends/WiFriends.java
发现2：
我还注意到以下行中使用的服务类型是“.tcp”.
serviceInfo = WifiP2pDnsSdServiceInfo.newInstance(SERVICE_NAME, "._tcp", record);
但是,根据Android开发人员指南,第二个参数(服务类型)应采用以下格式：“_ protocol._transportlayer”. http://developer.android.com/training/connect-devices-wirelessly/nsd.html.
在这里的演示代码developer.android.com/training/connect-devices-wirelessly/nsd-wifi-direct.html中,他们使用了“_presence._tcp”,其中“presence”是XMPP的消息传递协议.请参阅此处的详细说明,Available service types in WifiP2pDnsSdServiceInfo.newInstance.
我不确定在SVR记录中省略服务名称是否可以接受[任何有知识的人如果我错了,请更新我的部分]
标签：wifi-direct,android-networking,android,dns-sd 来源： https://codeday.me/bug/20191008/1874401.html