原文:Android自动连接指定的wifi，免密码或指定密码
一、运行时的状态
遇到一个这样的要求：“不进行扫描操作，怎么对指定的免密码WIFI进行连接（之前没有连接过）”，于是动手写了一个Demo，如图所示未连接成功时的状态，第一个编辑框让用户输入SSID，第二个编辑框输入密码，密码可以根据实例情况输入，也可以不输入密码，因为有些Wifi免密码。这里的免密码不是指可以破解wifi密码。注意图片中手机顶部的wifi图标，是没有的，说明此时并没有打开手机的wifi。在手机上运行状态如下所示：
输入SSID，点击连接后的状态，当手机的wifi没有打开时，程序将自动打开wifi，打开后再连接指定的wifi。
测试的手机信息如下：
二、功能实现
2.1、项目结构如下所示：
2.2、页面布局activity_main.xml文件如下所示：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/txtSSID"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="SSID："
android:textSize="@dimen/activity_horizontal_margin" />
<EditText
android:id="@+id/editSSID"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:text="FBI" >
<requestFocus />
</EditText>
<TextView
android:id="@+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Password："
android:textSize="@dimen/activity_horizontal_margin" />
<EditText
android:id="@+id/editPwd"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:text="" />
<Button
android:id="@+id/btnConnect"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Connect" />
<TextView
android:id="@+id/txtMessage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="" />
</LinearLayout>
2.3、清单文件AndroidManifest.xml内容如下，中间添加了对wifi访问的用户权限部分非常重要
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.wifigo"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="14"
android:targetSdkVersion="19" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" >
</uses-permission>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" >
</uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" >
</uses-permission>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" >
</uses-permission>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
2.4、Wifi连接管理类WifiConnector.java，有不少是参考热心网友的博客，谢谢了！
package com.example.wifigo;
import java.util.List;
import android.net.wifi.*;
import android.net.wifi.WifiConfiguration.AuthAlgorithm;
import android.net.wifi.WifiConfiguration.KeyMgmt;
import android.os.Handler;
import android.os.Message;
import android.text.TextUtils;
import android.util.Log;
public class WifiConnector {
Handler mHandler;
WifiManager wifiManager;
/**
* 向UI发送消息
* @param info 消息
*/
public void sendMsg(String info) {
if (mHandler != null) {
Message msg = new Message();
msg.obj = info;
mHandler.sendMessage(msg);// 向Handler发送消息
} else {
Log.e("wifi", info);
}
}
//WIFICIPHER_WEP是WEP ，WIFICIPHER_WPA是WPA，WIFICIPHER_NOPASS没有密码
public enum WifiCipherType {
WIFICIPHER_WEP, WIFICIPHER_WPA, WIFICIPHER_NOPASS, WIFICIPHER_INVALID
}
// 构造函数
public WifiConnector(WifiManager wifiManager) {
this.wifiManager = wifiManager;
}
// 提供一个外部接口，传入要连接的无线网
public void connect(String ssid, String password, WifiCipherType type) {
Thread thread = new Thread(new ConnectRunnable(ssid, password, type));
thread.start();
}
// 查看以前是否也配置过这个网络
private WifiConfiguration isExsits(String SSID) {
List<WifiConfiguration> existingConfigs = wifiManager
.getConfiguredNetworks();
for (WifiConfiguration existingConfig : existingConfigs) {
if (existingConfig.SSID.equals("\"" + SSID + "\"")) {
return existingConfig;
}
}
return null;
}
private WifiConfiguration createWifiInfo(String SSID, String Password,
WifiCipherType Type) {
WifiConfiguration config = new WifiConfiguration();
config.allowedAuthAlgorithms.clear();
config.allowedGroupCiphers.clear();
config.allowedKeyManagement.clear();
config.allowedPairwiseCiphers.clear();
config.allowedProtocols.clear();
config.SSID = "\"" + SSID + "\"";
// nopass
if (Type == WifiCipherType.WIFICIPHER_NOPASS) {
config.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
}
// wep
if (Type == WifiCipherType.WIFICIPHER_WEP) {
if (!TextUtils.isEmpty(Password)) {
if (isHexWepKey(Password)) {
config.wepKeys[0] = Password;
} else {
config.wepKeys[0] = "\"" + Password + "\"";
}
}
config.allowedAuthAlgorithms.set(AuthAlgorithm.OPEN);
config.allowedAuthAlgorithms.set(AuthAlgorithm.SHARED);
config.allowedKeyManagement.set(KeyMgmt.NONE);
config.wepTxKeyIndex = 0;
}
// wpa
if (Type == WifiCipherType.WIFICIPHER_WPA) {
config.preSharedKey = "\"" + Password + "\"";
config.hiddenSSID = true;
config.allowedAuthAlgorithms
.set(WifiConfiguration.AuthAlgorithm.OPEN);
config.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.TKIP);
config.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.WPA_PSK);
config.allowedPairwiseCiphers
.set(WifiConfiguration.PairwiseCipher.TKIP);
// 此处需要修改否则不能自动重联
// config.allowedProtocols.set(WifiConfiguration.Protocol.WPA);
config.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.CCMP);
config.allowedPairwiseCiphers
.set(WifiConfiguration.PairwiseCipher.CCMP);
config.status = WifiConfiguration.Status.ENABLED;
}
return config;
}
// 打开wifi功能
private boolean openWifi() {
boolean bRet = true;
if (!wifiManager.isWifiEnabled()) {
bRet = wifiManager.setWifiEnabled(true);
}
return bRet;
}
class ConnectRunnable implements Runnable {
private String ssid;
private String password;
private WifiCipherType type;
public ConnectRunnable(String ssid, String password, WifiCipherType type) {
this.ssid = ssid;
this.password = password;
this.type = type;
}
@Override
public void run() {
try {
// 打开wifi
openWifi();
sendMsg("opened");
Thread.sleep(200);
// 开启wifi功能需要一段时间(我在手机上测试一般需要1-3秒左右)，所以要等到wifi
// 状态变成WIFI_STATE_ENABLED的时候才能执行下面的语句
while (wifiManager.getWifiState() == WifiManager.WIFI_STATE_ENABLING) {
try {
// 为了避免程序一直while循环，让它睡个100毫秒检测……
Thread.sleep(100);
} catch (InterruptedException ie) {
}
}
WifiConfiguration wifiConfig = createWifiInfo(ssid, password,
type);
//
if (wifiConfig == null) {
sendMsg("wifiConfig is null!");
return;
}
WifiConfiguration tempConfig = isExsits(ssid);
if (tempConfig != null) {
wifiManager.removeNetwork(tempConfig.networkId);
}
int netID = wifiManager.addNetwork(wifiConfig);
boolean enabled = wifiManager.enableNetwork(netID, true);
sendMsg("enableNetwork status enable=" + enabled);
boolean connected = wifiManager.reconnect();
sendMsg("enableNetwork connected=" + connected);
sendMsg("连接成功!");
} catch (Exception e) {
// TODO: handle exception
sendMsg(e.getMessage());
e.printStackTrace();
}
}
}
private static boolean isHexWepKey(String wepKey) {
final int len = wepKey.length();
// WEP-40, WEP-104, and some vendors using 256-bit WEP (WEP-232?)
if (len != 10 && len != 26 && len != 58) {
return false;
}
return isHex(wepKey);
}
private static boolean isHex(String key) {
for (int i = key.length() - 1; i >= 0; i--) {
final char c = key.charAt(i);
if (!(c >= '0' && c <= '9' || c >= 'A' && c <= 'F' || c >= 'a'
&& c <= 'f')) {
return false;
}
}
return true;
}
}
2.5、MainActivity.java代码，完成接收用户的输入与调用wifi连接功能，如下所示：
package com.example.wifigo;
import com.example.wifigo.WifiConnector.WifiCipherType;
import android.app.Activity;
import android.content.Context;
import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity {
Button btnConnect;
WifiManager wifiManager;
WifiConnector wac;
TextView textView1;
EditText editPwd;
EditText editSSID;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnConnect = (Button) findViewById(R.id.btnConnect);
textView1 = (TextView) findViewById(R.id.txtMessage);
wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
wac = new WifiConnector(wifiManager);
editPwd=(EditText) findViewById(R.id.editPwd);
editSSID=(EditText) findViewById(R.id.editSSID);
wac.mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
// 操作界面
textView1.setText(textView1.getText()+"\n"+msg.obj+"");
super.handleMessage(msg);
}
};
btnConnect.setOnClickListener(new Button.OnClickListener() {
@Override
public void onClick(View v) {
try {
wac.connect(editSSID.getText().toString(), editPwd.getText().toString(),
editPwd.getText().toString().equals("")?WifiCipherType.WIFICIPHER_NOPASS:WifiCipherType.WIFICIPHER_WPA);
} catch (Exception e) {
textView1.setText(e.getMessage());
}
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.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();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
2.6、小结
时间比较紧，代码比较粗糙，这毕竟只是一个demo，如果您需要使用在商业项目中这可能只具有抛砖引玉的作用了；另外测试时发现如果手机的wifi没有打开，依靠程序打开时程序会崩溃，后面发现有可能是打开wifi时需要一段时间，所以代码中增加了一些人为的延时操作，尽量用更加优雅的办法替代；我使用一台Android 4.x.x的meizu note 1手机和一个DLink DIR-600N的老路由器测试没有问题，使用自己的笔记本电脑作热点，带密码连接没有问题，这不代表在其它环境下就正常了。
2.7、参考示例：
时间： 2024-08-03 09:48:06