我目前正在开发我自己的应用程序，它应该通过 WiFi Direct 将消息发送到连接的其他设备。在 Android 9 及更低版本上，设备的发现已成功启动，但在 Android 10 上却没有。
这是我的 MainActivity.java 文件:
package com.shuzo.musicshare;
import android.Manifest;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.net.wifi.WifiManager;
import android.net.wifi.p2p.WifiP2pConfig;
import android.net.wifi.p2p.WifiP2pDevice;
import android.net.wifi.p2p.WifiP2pDeviceList;
import android.net.wifi.p2p.WifiP2pInfo;
import android.net.wifi.p2p.WifiP2pManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.StrictMode;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Switch;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
Button btnDiscover, btnSend;
Switch switchOnOff;
ListView listView;
TextView readMsgBox, connectionStatus;
EditText writeMsg;
WifiManager wifiManager;
WifiP2pManager mManager;
WifiP2pManager.Channel mChannel;
BroadcastReceiver mReceiver;
IntentFilter mIntentFilter;
List<WifiP2pDevice> peers = new ArrayList<WifiP2pDevice>();
String[] deviceNameArray;
WifiP2pDevice[] deviceArray;
static final int MESSAGE_READ = 1;
ServerClass serverClass;
List<ClientClass> clientClass = new ArrayList<>();
SendReceive sendReceive;
@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);
initialWork();
exqListener();
}
Handler handler = new Handler(new Handler.Callback() {
@Override
public boolean handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_READ:
byte[] readBuff = (byte[]) msg.obj;
String tempMsg = new String(readBuff, 0, msg.arg1);
readMsgBox.setText(tempMsg);
break;
}
return true;
}
});
private void exqListener() {
switchOnOff.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
wifiManager.setWifiEnabled(b);
}
});
btnDiscover.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
mManager.discoverPeers(mChannel, new WifiP2pManager.ActionListener() {
@Override
public void onSuccess() {
if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_DENIED) {
ActivityCompat.requestPermissions(MainActivity.this, new String[] { Manifest.permission.ACCESS_COARSE_LOCATION },1);
}
connectionStatus.setText("Discovery started");
}
@Override
public void onFailure(int i) {
connectionStatus.setText("Discovery starting failed");
}
});
}
});
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
final WifiP2pDevice device = deviceArray[i];
WifiP2pConfig config = new WifiP2pConfig();
config.deviceAddress = device.deviceAddress;
mManager.connect(mChannel, config, new WifiP2pManager.ActionListener() {
@Override
public void onSuccess() {
Toast.makeText(getApplicationContext(), "Connected to " + device.deviceName, Toast.LENGTH_SHORT).show();
}
@Override
public void onFailure(int i) {
Toast.makeText(getApplicationContext(), "Not Connected", Toast.LENGTH_SHORT).show();
}
});
}
});
btnSend.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String msg=writeMsg.getText().toString();
sendReceive.write(msg.getBytes());
}
});
}
private void initialWork() {
btnDiscover = findViewById(R.id.discover);
btnSend = findViewById(R.id.sendButton);
switchOnOff = findViewById(R.id.switchOnOff);
wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
switchOnOff.setChecked(wifiManager.isWifiEnabled());
listView = findViewById(R.id.peerListView);
readMsgBox = findViewById(R.id.readMsg);
connectionStatus = findViewById(R.id.connectionStatus);
writeMsg = findViewById(R.id.writeMsg);
mManager = (WifiP2pManager) getSystemService(Context.WIFI_P2P_SERVICE);
mChannel = mManager.initialize(this, getMainLooper(), null);
mReceiver = new WiFiDirectBroadcastReceiver(mManager, mChannel, this);
mIntentFilter = new IntentFilter();
mIntentFilter.addAction(WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION);
mIntentFilter.addAction(WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION);
mIntentFilter.addAction(WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION);
mIntentFilter.addAction(WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION);
}
WifiP2pManager.PeerListListener peerListListener = new WifiP2pManager.PeerListListener() {
@Override
public void onPeersAvailable(WifiP2pDeviceList peerList) {
if (!peerList.getDeviceList().equals(peers)) {
peers.clear();
peers.addAll(peerList.getDeviceList());
deviceNameArray = new String[peerList.getDeviceList().size()];
deviceArray = new WifiP2pDevice[peerList.getDeviceList().size()];
int index = 0;
for (WifiP2pDevice device : peerList.getDeviceList()) {
deviceNameArray[index] = device.deviceName;
deviceArray[index] = device;
index++;
}
ArrayAdapter<String> adapter = new ArrayAdapter<>(getApplicationContext(), android.R.layout.simple_list_item_1, deviceNameArray);
listView.setAdapter(adapter);
}
if (peers.size() == 0) {
Toast.makeText(getApplicationContext(), "No devices found", Toast.LENGTH_SHORT).show();
}
}
};
WifiP2pManager.ConnectionInfoListener connectionInfoListener = new WifiP2pManager.ConnectionInfoListener() {
@Override
public void onConnectionInfoAvailable(WifiP2pInfo wifiP2pInfo) {
final InetAddress groupOwnerAddress = wifiP2pInfo.groupOwnerAddress;
if (wifiP2pInfo.groupFormed && wifiP2pInfo.isGroupOwner) {
connectionStatus.setText("Host");
serverClass = new ServerClass();
serverClass.start();
} else if (wifiP2pInfo.groupFormed) {
connectionStatus.setText("Client");
ClientClass client = new ClientClass(groupOwnerAddress);
clientClass.add(client);
client.start();
}
}
};
@Override
protected void onResume() {
super.onResume();
registerReceiver(mReceiver, mIntentFilter);
}
@Override
protected void onPause() {
super.onPause();
unregisterReceiver(mReceiver);
}
private class SendReceive extends Thread {
private Socket socket;
private InputStream inputStream;
private OutputStream outputStream;
public SendReceive(Socket skt) {
socket = skt;
try {
inputStream = socket.getInputStream();
outputStream = socket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void run() {
byte[] buffer = new byte[1024];
int bytes;
while (socket != null) {
try {
bytes = inputStream.read(buffer);
if (bytes > 0) {
handler.obtainMessage(MESSAGE_READ, bytes, -1, buffer).sendToTarget();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
public void write(byte[] bytes) {
try {
outputStream.write(bytes);
} catch (IOException e) {
e.printStackTrace();
}
}
}
public class ServerClass extends Thread {
Socket socket;
ServerSocket serverSocket;
@Override
public void run() {
try {
serverSocket = new ServerSocket(8888);
socket = serverSocket.accept();
sendReceive = new SendReceive(socket);
sendReceive.start();
} catch (IOException e) {
e.printStackTrace();
}
}
}
public class ClientClass extends Thread {
Socket socket;
String hostAdd;
public ClientClass (InetAddress hostAddress) {
hostAdd = hostAddress.getHostAddress();
socket = new Socket();
}
@Override
public void run() {
try {
socket.connect(new InetSocketAddress(hostAdd, 8888), 500);
sendReceive = new SendReceive(socket);
sendReceive.start();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
这是我的 WiFiDirectBroadcastReceiver 类:
package com.shuzo.musicshare;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.net.NetworkInfo;
import android.net.wifi.p2p.WifiP2pManager;
import android.widget.Toast;
public class WiFiDirectBroadcastReceiver extends BroadcastReceiver {
private WifiP2pManager mManager;
private WifiP2pManager.Channel mChannel;
private MainActivity mActivity;
public WiFiDirectBroadcastReceiver(WifiP2pManager manager, WifiP2pManager.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 (WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION.equals(action)) {
int state = intent.getIntExtra(WifiP2pManager.EXTRA_WIFI_STATE, -1);
if (state == WifiP2pManager.WIFI_P2P_STATE_ENABLED) {
Toast.makeText(context, "WiFi is enabled", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(context, "WiFi is disabled", Toast.LENGTH_SHORT).show();
}
} else if (WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION.equals(action)) {
if (mManager != null) {
mManager.requestPeers(mChannel, mActivity.peerListListener);
}
} else if (WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION.equals(action)) {
if (mManager == null) {
return;
}
NetworkInfo networkInfo = intent.getParcelableExtra(WifiP2pManager.EXTRA_NETWORK_INFO);
if (networkInfo.isConnected()) {
mManager.requestConnectionInfo(mChannel, mActivity.connectionInfoListener);
} else {
mActivity.connectionStatus.setText("Device disconnected");
}
} else if (WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION.equals(action)) {
// Respond to this device's wifi state changing
}
}
}
我还请求我的 list 文件中所需的所有权限:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.shuzo.musicshare">
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
我的 activity_main.xml 看起来像这样:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/ConstraintLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<Button
android:id="@+id/discover"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@id/connectionStatus"
android:layout_alignBottom="@id/connectionStatus"
android:layout_centerHorizontal="true"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:text="discover"
app:layout_constraintStart_toEndOf="@+id/switchOnOff"
app:layout_constraintTop_toBottomOf="@+id/connectionStatus" />
<ListView
android:id="@+id/peerListView"
android:layout_width="match_parent"
android:layout_height="200dp"
android:layout_alignParentStart="true"
android:layout_marginTop="16dp"
android:background="@android:color/holo_orange_light"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/discover" />
<TextView
android:id="@+id/readMsg"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/peerListView"
android:layout_alignParentStart="true"
android:layout_alignParentEnd="true"
android:layout_marginTop="16dp"
android:text="Message"
android:textAlignment="center"
android:textSize="20sp"
android:textStyle="italic"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/peerListView" />
<EditText
android:id="@+id/writeMsg"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentBottom="true"
android:layout_toStartOf="@+id/sendButton"
android:ems="10"
android:inputType="textPersonName"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="@+id/sendButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentBottom="true"
android:text="Send"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toEndOf="@+id/writeMsg" />
<TextView
android:id="@+id/connectionStatus"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginTop="16dp"
android:text="Connection Status"
android:textAlignment="center"
android:textColor="@android:color/holo_blue_dark"
android:textSize="18sp"
android:textStyle="italic"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Switch
android:id="@+id/switchOnOff"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginTop="24dp"
android:text="WiFi"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/connectionStatus" />
</androidx.constraintlayout.widget.ConstraintLayout>
当我按下 Android 9 上的发现按钮时， Activity 顶部的 TextView 会显示“发现已开始”，如果我使用运行 Android 8 的第二台设备执行此操作，我可以通过 ListView 连接这两个设备。如果我想在 Android 10 设备上执行此操作，TextView 会显示“发现启动失败”。
手机上的Activity是这样的:
Activity on the phone
有人知道如何在 Android 10 上修复此发现失败吗？
编辑:Android 10 上的测试设备是三星 Galaxy A40。
最佳答案
根据 documentation , 你需要权限 android.permission.ACCESS_FINE_LOCATION而不是 android.permission.ACCESS_COARSE_LOCATION .
关于java - Android 10 设备不开始发现 wifi direct，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/60857880/