wifi的使用

1.获取系统权限

<uses-permission android:name="android.permission.INTERNET" android:required="true"/><uses-permission android:name="android.permission.CHANGE_WIFI_STATE" android:required="true"/><uses-permission android:name="android.permission.ACCESS_WIFI_STATE" android:required="true"/>

2.主函数

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemClickListener {    private final IntentFilter intentFilter = new IntentFilter();    private WifiP2pManager.Channel mChannel;    private WifiP2pManager mManager;    private WiFiDirectBroadcastReceiver receiver;    private List<WifiP2pDevice> peers = new ArrayList();    private List<String> peersStr = new ArrayList<>();    private ListView lv;    private ArrayAdapter<String> mAdapter;//    private WifiP2pManager.PeerListListener peerListListener = new WifiP2pManager.PeerListListener() {//        @Override//        public void onPeersAvailable(WifiP2pDeviceList peerList) {////            //旧的不去，新的不来//            peers.clear();//            peers.addAll(peerList.getDeviceList());////            //如果AdapterView可以处理该数据，则把变更通知它。比如，如果你有可用对等点的ListView，那就发起一次更新。//            //            ((WiFiPeerListAdapter) getListAdapter()).notifyDataSetChanged();//            if (peers.size() == 0) {//                Log.d("sxl", "No devices found");//                return;//            }//        }//    }    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        //表示Wi-Fi对等网络状态发生了改变        intentFilter.addAction(WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION);        //表示可用的对等点的列表发生了改变        intentFilter.addAction(WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION);        //表示Wi-Fi对等网络的连接状态发生了改变        intentFilter.addAction(WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION);        //设备配置信息发生了改变        intentFilter.addAction(WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION);        mManager = (WifiP2pManager) getSystemService(Context.WIFI_P2P_SERVICE);        mChannel = mManager.initialize(this, getMainLooper(), null);        lv = (ListView) findViewById(R.id.lv);        mAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,peersStr);        lv.setAdapter(mAdapter);        lv.setOnItemClickListener(this);    }    @Override    protected void onResume() {        super.onResume();        receiver = new WiFiDirectBroadcastReceiver(mManager, mChannel, this);        registerReceiver(receiver, intentFilter);    }    @Override    protected void onPause() {        super.onPause();        unregisterReceiver(receiver);    }    //点击搜索周围wifiDirect设备    public void onClick(View view) {        mManager.discoverPeers(mChannel, new WifiP2pManager.ActionListener() {            @Override            public void onSuccess() {                //查找初始化成功时的处理写在这里。                //实际上并没有发现任何服务，所以该方法可以置空。                //对等点搜索的代码在onReceive方法中，详见下文。            }            @Override            public void onFailure(int reasonCode) {                Log.e("sxl","sxl discoverPeers() onFailure reasonCode="+reasonCode);                //查找初始化失败时的处理写在这里。                //警告用户出错了。            }        });    }    @Override    public void onItemClick(AdapterView<?> adapterView, View view, int pos, long l) {        WifiP2pDevice peer = peers.get(pos);        connect(peer);//连接    }    public void connect(final WifiP2pDevice device) {        Log.i("sxl", "connect: ");        WifiP2pConfig config = new WifiP2pConfig();        config.deviceAddress = device.deviceAddress;//mac地址        config.wps.setup = 0;        mManager.connect(mChannel, config, new WifiP2pManager.ActionListener() {            public void onSuccess() {                Log.e("sxl", "connect onSuccess: "+device.deviceAddress);            }            public void onFailure(int reason) {                Log.e("sxl", "connect onFailure: " + reason);            }        });    }    class WiFiDirectBroadcastReceiver extends BroadcastReceiver{        private WifiP2pManager mManager;        private WifiP2pManager.Channel mChannel;        private Activity activity;        public WiFiDirectBroadcastReceiver(WifiP2pManager manager, WifiP2pManager.Channel channel, Activity activity){            this.mManager = manager;            this.mChannel = channel;            this.activity = activity;        }        @Override        public void onReceive(Context context, Intent intent) {            String action = intent.getAction();            if (WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION.equals(action)) {                //确定Wi-Fi Direct模式是否已经启用，并提醒Activity。                int state = intent.getIntExtra(WifiP2pManager.EXTRA_WIFI_STATE, -1);                if (state == WifiP2pManager.WIFI_P2P_STATE_ENABLED) {//                    activity.setIsWifiP2pEnabled(true);                } else {//                    activity.setIsWifiP2pEnabled(false);                }            } else if (WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION.equals(action)) {                //发现周围设备变化                mManager.requestPeers(mChannel, new MypeerListListener());            } else if (WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION.equals(action)) {                //连接状态已经改变！需要获取IP                NetworkInfo device1 = (NetworkInfo)intent.getParcelableExtra("networkInfo");                if(device1.isConnected()) {                    Log.i("sxl", "onReceive: WIFI_P2P_CONNECTION_CHANGED_ACTION  networkInfo.isConnected()");                    this.mManager.requestConnectionInfo(this.mChannel, new WifiP2pManager.ConnectionInfoListener() {                        public void onConnectionInfoAvailable(WifiP2pInfo info) {                            final String ip = info.groupOwnerAddress.getHostAddress();                            Log.e("sxl", "ip =" + ip + ","+getWFDMacAddress());                        }                    });                }            } else if (WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION.equals(action)) {//                DeviceListFragment fragment = (DeviceListFragment) activity.getFragmentManager()//                        .findFragmentById(R.id.frag_list);//                fragment.updateThisDevice((WifiP2pDevice) intent.getParcelableExtra(//                        WifiP2pManager.EXTRA_WIFI_P2P_DEVICE));            }        }    }    class MypeerListListener implements PeerListListener{        public void onPeersAvailable(WifiP2pDeviceList wifiP2pDeviceList) {            Log.i("sxl", "onPeersAvailable:");            MainActivity.this.peers.clear();            MainActivity.this.peersStr.clear();            MainActivity.this.peers.addAll(wifiP2pDeviceList.getDeviceList());            for (int i = 0; i <MainActivity.this.peers.size() ; i++) {                MainActivity.this.peersStr.add(MainActivity.this.peers.get(i).toString());            }            MainActivity.this.mAdapter.notifyDataSetChanged();            int size = MainActivity.this.peers.size();            Log.i("sxl", "onPeersAvailable: size " + size);            for(int i = 0; i < size; ++i) {                Log.e("sxl", i + " onPeersAvailable: for " + ((WifiP2pDevice)MainActivity.this.peers.get(i)).deviceName);                Log.i("sxl", i + " onPeersAvailable: mac " + ((WifiP2pDevice)MainActivity.this.peers.get(i)).deviceAddress);                Log.i("sxl", "");            }        }    };    public String getWFDMacAddress() {        try {            ArrayList interfaces = Collections.list(NetworkInterface.getNetworkInterfaces());            Iterator var2 = interfaces.iterator();            while(var2.hasNext()) {                NetworkInterface ntwInterface = (NetworkInterface)var2.next();                if(ntwInterface.getName().equalsIgnoreCase("p2p0")) {                    byte[] byteMac = ntwInterface.getHardwareAddress();                    if(byteMac == null) {                        return "";                    }                    StringBuilder strBuilder = new StringBuilder();                    for(int i = 0; i < byteMac.length; ++i) {                        strBuilder.append(String.format("%02X:", new Object[]{Byte.valueOf(byteMac[i])}));                    }                    if(strBuilder.length() > 0) {                        strBuilder.deleteCharAt(strBuilder.length() - 1);                    }                    return strBuilder.toString();                }            }        } catch (Exception var7) {            ;        }        return "";    }}

发送的class

public class SendText {    protected int port = 8998;    protected Socket socket;    protected Writer writer;    protected BufferedReader br;    public SendText(final String host, final String msg) {        (new Thread(new Runnable() {            public void run() {                try {                    SendText.this.socket = new Socket(host, SendText.this.port);                    SendText.this.writer = new OutputStreamWriter(SendText.this.socket.getOutputStream(), "UTF-8");                    SendText.this.br = new BufferedReader(new InputStreamReader(SendText.this.socket.getInputStream(), "UTF-8"));                } catch (UnknownHostException var5) {                    var5.printStackTrace();                } catch (IOException var6) {                    var6.printStackTrace();                }                try {                    if(SendText.this.writer == null) {                        System.out.println("write is null");                        return;                    }                    SendText.this.writer.write(msg);                    SendText.this.writer.write("eof\n");                    SendText.this.writer.flush();                    SendText.this.writer.close();                    SendText.this.socket.close();                } catch (IOException var4) {                    var4.printStackTrace();                    try {                        SendText.this.writer.close();                        SendText.this.socket.close();                    } catch (IOException var3) {                        var3.printStackTrace();                    }                }            }        })).start();    }}

3.主布局

<LinearLayout    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context="alice.bw.com.wifidirectdemo.MainActivity">    <Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:onClick="onClick"        android:text="搜索周围wifiDirect设备"/>    <ListView        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/lv"></ListView></LinearLayout>