android – WifiP2pManager.requestPeers()不断返回onPeersAvailable()中的旧对等体

问题如下：我正在从android做wifip2p教程.我在MainActivity上使用此FloaTingActionButton手动调用discoverPeers().然后在WifiDirectBroadcastReceiver类中广播和接收WIFI_P2P_PEERS_CHANGED_ACTION.在那里我调用requestPeers(),它只在至少有一个可发现的对等体时调用onPeersAvailable()(这很有意义.)

然而问题是,一旦它发现了一个对等体,它将永远不会离开列表.即使我关闭检测到的设备.让我用一个例子来说明：

> 3个设备(A,B和C),全部支持wifi-direct.
>在设备A上启动应用程序,保持设备B和C关闭.
>尝试用A检测,没有检测到任何东西.没问题.
>打开设备B,转到wifi-direct设置,扫描.
>尝试用A检测,检测B.没问题.
>关闭设备B.
>尝试用A检测,没有检测到任何东西.没问题.
>打开设备C,检测C和B.但设备B仍然关闭.为什么它仍然被检测到？ (最糟糕的是,它被检测到状态3,对应于AVAILABLE)

这种情况发生在设备角色的任何排列上.所以问题实际上在代码中,因为它们都通过官方的wifi-direct设置窗口正常运行和检测.

这是我的MainActivity：

package com.gett.wifip2ptest;

import android.content.broadcastReceiver;
import android.content.IntentFilter;
import android.net.wifi.p2p.wifip2pDeviceList;
import android.os.bundle;
import android.support.design.widget.FloaTingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;

import android.content.Context;
import android.net.wifi.p2p.@L_344_2@manager;
import android.net.wifi.p2p.@L_344_2@manager.ChAnnel;
import android.net.wifi.p2p.@L_344_2@manager.PeerListListener;
import android.net.wifi.p2p.wifip2pDevice;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity implements PeerListListener{

    private @L_344_2@manager mManager;
    private ChAnnel mChAnnel;
    private BroadcastReceiver mReceiver;

    privatE intentFilter mIntentFilter;

    private List<wifip2pDevice> peers = new ArrayList<wifip2pDevice>();

    @Override
    protected void onCreate(Bundle savedInstanceStatE) {
        super.onCreate(savedInstanceStatE);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloaTingActionButton fab = (FloaTingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.onClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view,"replace with your own action",Snackbar.LENGTH_LONG)
                        .setAction("Action",null).show();

//                If the discovery process succeeds and detects peers,the system broadcasts the
//                WIFI_P2P_PEERS_CHANGED_ACTION intent.
                mManager.discoverPeers(mChAnnel,new @L_344_2@manager.ActionListener() {
                    @Override
                    public void onsuccess() {
                        Toast.makeText(MainActivity.this,"Discovery Initiated",Toast.LENGTH_SHORT).show();
                    }

                    @Override
                    public void onFailure(int reasonCodE) {
                        Toast.makeText(MainActivity.this,"Discovery Failed : " + reasonCode,Toast.LENGTH_SHORT).show();
                    }
                });
            }
        });

        mManager = (@L_344_2@manager) getSystemservice(Context.WIFI_P2P_serviCE);
        mChAnnel = mManager.initialize(this,getMainLooper(),null);
        mReceiver = new WiFiDirectBroadcastReceiver(mManager,mChAnnel,this);

        mIntentFilter = new IntentFilter();
        mIntentFilter.addAction(@L_344_2@manager.WIFI_P2P_STATE_CHANGED_ACTION);
        mIntentFilter.addAction(@L_344_2@manager.WIFI_P2P_PEERS_CHANGED_ACTION);
        mIntentFilter.addAction(@L_344_2@manager.WIFI_P2P_CONNECTION_CHANGED_ACTION);
        mIntentFilter.addAction(@L_344_2@manager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION);
    }

    /* register the broadcast receiver with thE intent values to be matched */
    @Override
    protected void onResume() {
        super.onResume();
        registerReceiver(mReceiver,mIntentFilter);
    }

    /* unregister the broadcast receiver */
    @Override
    protected void onPause() {
        super.onPause();
        unregisterReceiver(mReceiver);
    }

    @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);
    }

    /**
     * This function is called by requestPeers upon receiving the peers list.
     * @param peerList
     */
    @Override
    public void onPeersAvailable(wifip2pDeviceList peerList) {
        peers.clear();
        System.out.println("Peers cleared : " + peers);

        peers.addAll(peerList.getDeviceList());

        System.out.println("Peers : " + peers);
        if (peers.size() == 0) {
            System.out.println("No devices found");
            return;
        }
    }
}

这是WiFiDirectBroadCastReceiver：

package com.gett.wifip2ptest;

import android.content.broadcastReceiver;
import android.net.wifi.p2p.@L_344_2@manager;
import android.net.wifi.p2p.@L_344_2@manager.ChAnnel;
import android.net.wifi.p2p.@L_344_2@manager.PeerListListener;
import android.content.Context;
import android.content.Intent;

public class WiFiDirectBroadcastReceiver extends BroadcastReceiver {

    private @L_344_2@manager mManager;
    private ChAnnel mChAnnel;
    private MainActivity mActivity;

    public WiFiDirectBroadcastReceiver(@L_344_2@manager manager,ChAnnel chAnnel,MainActivity activity) {
        super();
        this.mManager = manager;
        this.mChAnnel = chAnnel;
        this.mActivity = activity;
    }

    @Override
    public void onReceive(Context context,Intent intent) {
        String action = intent.getAction();

        if (@L_344_2@manager.WIFI_P2P_STATE_CHANGED_ACTION.equals(action)) {
            // check to see if Wi-Fi is enabled and notify appropriate activity
            int state = intent.getIntextra(@L_344_2@manager.EXTRA_WIFI_STATE,-1);
            if (state == @L_344_2@manager.WIFI_P2P_STATE_ENABLED) {
                // Wifi P2P is enabled
                System.out.println("Wifi Direct has been enabled.");
            } else {
                // Wi-Fi P2P is not enabled
                System.out.println("Wifi Direct is NOT enabled.");
            }
        } else if (@L_344_2@manager.WIFI_P2P_PEERS_CHANGED_ACTION.equals(action)) {
            // Call @L_344_2@manager.requestPeers() to get a list of current peers
            System.out.println("Peers changed.");

            // request available peers from the wifi p2p manager. This is an
            // asynchronous call and the calling activity is notified with a
            // callBACk on PeerListlistener.onPeersAvailable()
            if (mManager != null) {
                mManager.requestPeers(mChAnnel,(PeerListListener) mActivity);
            }
        } else if (@L_344_2@manager.WIFI_P2P_CONNECTION_CHANGED_ACTION.equals(action)) {
            // Respond to new connection or disconnections
        } else if (@L_344_2@manager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION.equals(action)) {
            // Respond to this device's wifi state changing
        }
    }
}

以下是其中一个被关闭时检测到两个对等体的示例：

02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out: Peers : [Device: Galaxy J1-2
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  deviceAddress: 2a:27:bf:3a:2e:55
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  priMary type: 10-0050F204-5
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  secondary type: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  wps: 392
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  grpcapab: 0
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  devcapab: 37
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  status: 3
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  wfdInfo: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  groupownerAddress: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  GOdeviceName: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  interfaceAddress: 
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  SConnecTinfo : null,Device: Test User (Galaxy J1)
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  deviceAddress: 2a:27:bf:3a:4a:8b
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  priMary type: 10-0050F204-5
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  secondary type: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  wps: 392
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  grpcapab: 0
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  devcapab: 37
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  status: 3
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  wfdInfo: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  groupownerAddress: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  GOdeviceName: null
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  interfaceAddress: 
02-18 16:31:56.406 20833-20833/com.gett.wifip2ptest I/System.out:  SConnecTinfo : null]