写了一个工具类来辅助处理wifi相关状态控制和连接等功能，参考了网上的相关文件，并修改了里面的一些bug和问题，本文给出的方法均经过验证可用～

package com.xys.jrdtraining.network;

import java.util.List;

import android.content.Context;
import android.net.wifi.ScanResult;
import android.net.wifi.WifiConfiguration;
import android.net.wifi.WifiInfo;
import android.net.wifi.WifiManager;
import android.net.wifi.WifiManager.WifiLock;

/**
 * wifi ctrl utils class
 * 
 * @author yisheng.xu
 * 
 */
public class WifiOpenHelper {
	// 定义WifiManager对象
	private WifiManager mWifiManager;
	// 定义WifiInfo对象
	private WifiInfo mWifiInfo;
	// 扫描出的网络连接列表
	private List<ScanResult> mWifiList;
	// 网络连接列表
	private List<WifiConfiguration> mWifiConfiguration;
	// 定义一个WifiLock
	WifiLock mWifiLock;

	// 构造器
	public WifiOpenHelper(Context context) {
		// 取得WifiManager对象
		mWifiManager = (WifiManager) context
				.getSystemService(Context.WIFI_SERVICE);
		// 取得WifiInfo对象
		mWifiInfo = mWifiManager.getConnectionInfo();
	}

	// 打开WIFI
	public void openWifi() {
		if (!mWifiManager.isWifiEnabled()) {
			mWifiManager.setWifiEnabled(true);
		}
	}

	// 断开当前网络
	public void disconnectWifi() {
		if (!mWifiManager.isWifiEnabled()) {
			mWifiManager.disconnect();
		}
	}

	// 关闭WIFI
	public void closeWifi() {
		if (mWifiManager.isWifiEnabled()) {
			mWifiManager.setWifiEnabled(false);
		}
	}

	// 检查当前WIFI状态
	public int checkState() {
		return mWifiManager.getWifiState();
	}

	// 锁定WifiLock
	public void acquireWifiLock() {
		mWifiLock.acquire();
	}

	// 解锁WifiLock
	public void releaseWifiLock() {
		// 判断时候锁定
		if (mWifiLock.isHeld()) {
			mWifiLock.acquire();
		}
	}

	// 创建一个WifiLock
	public void creatWifiLock() {
		mWifiLock = mWifiManager.createWifiLock("Test");
	}

	// 得到配置好的网络
	public List<WifiConfiguration> getConfiguration() {
		return mWifiConfiguration;
	}

	// 指定配置好的网络进行连接
	public void connectConfiguration(int index) {
		// 索引大于配置好的网络索引返回
		if (index > mWifiConfiguration.size()) {
			return;
		}
		// 连接配置好的指定ID的网络
		mWifiManager.enableNetwork(mWifiConfiguration.get(index).networkId,
				true);
	}

	public void startScan() {
		mWifiManager.startScan();
		// 得到扫描结果
		mWifiList = mWifiManager.getScanResults();
		// 得到配置好的网络连接
		mWifiConfiguration = mWifiManager.getConfiguredNetworks();
	}

	// 得到网络列表
	public List<ScanResult> getWifiList() {
		return mWifiList;
	}

	// 查看扫描结果
	public StringBuilder lookUpScan() {
		StringBuilder stringBuilder = new StringBuilder();
		for (int i = 0; i < mWifiList.size(); i++) {
			stringBuilder.append("Index_" + Integer.valueOf(i + 1).toString()
					+ ":");
			// 将ScanResult信息转换成一个字符串包
			// 其中把包括：BSSID、SSID、capabilities、frequency、level
			stringBuilder.append((mWifiList.get(i)).toString());
			stringBuilder.append("/n");
		}
		return stringBuilder;
	}

	// 得到MAC地址
	public String getMacAddress() {
		return (mWifiInfo == null) ? "NULL" : mWifiInfo.getMacAddress();
	}

	// 得到接入点的BSSID
	public String getBSSID() {
		return (mWifiInfo == null) ? "NULL" : mWifiInfo.getBSSID();
	}

	// 得到IP地址
	public int getIPAddress() {
		return (mWifiInfo == null) ? 0 : mWifiInfo.getIpAddress();
	}

	// 得到连接的ID
	public int getNetworkId() {
		return (mWifiInfo == null) ? 0 : mWifiInfo.getNetworkId();
	}

	// 得到WifiInfo的所有信息包
	public String getWifiInfo() {
		return (mWifiInfo == null) ? "NULL" : mWifiInfo.toString();
	}

	// 添加一个网络并连接
	public void addNetwork(WifiConfiguration wcg) {
		int wcgID = mWifiManager.addNetwork(wcg);
		boolean b = mWifiManager.enableNetwork(wcgID, true);
		System.out.println("a--" + wcgID);
		System.out.println("b--" + b);
	}

	// 断开指定ID的网络
	public void disconnectWifi(int netId) {
		mWifiManager.disableNetwork(netId);
		mWifiManager.disconnect();
	}

	public WifiConfiguration CreateWifiInfo(String SSID, String Password,
			int Type) {
		WifiConfiguration config = new WifiConfiguration();
		config.allowedAuthAlgorithms.clear();
		config.allowedGroupCiphers.clear();
		config.allowedKeyManagement.clear();
		config.allowedPairwiseCiphers.clear();
		config.allowedProtocols.clear();
		config.SSID = "\"" + SSID + "\"";

		WifiConfiguration tempConfig = this.IsExsits(SSID);
		if (tempConfig != null) {
			mWifiManager.removeNetwork(tempConfig.networkId);
		}

		if (Type == 1) // WIFICIPHER_NOPASS
		{
			config.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
		}
		if (Type == 2) // WIFICIPHER_WEP
		{
			config.hiddenSSID = true;
			config.wepKeys[0] = "\"" + Password + "\"";
			config.allowedAuthAlgorithms
					.set(WifiConfiguration.AuthAlgorithm.SHARED);
			config.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.CCMP);
			config.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.TKIP);
			config.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.WEP40);
			config.allowedGroupCiphers
					.set(WifiConfiguration.GroupCipher.WEP104);
			config.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
			config.wepTxKeyIndex = 0;
		}
		if (Type == 3) // 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);
			config.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.CCMP);
			config.allowedPairwiseCiphers
					.set(WifiConfiguration.PairwiseCipher.CCMP);
			config.status = WifiConfiguration.Status.ENABLED;
		}
		return config;
	}

	private WifiConfiguration IsExsits(String SSID) {
		List<WifiConfiguration> existingConfigs = mWifiManager
				.getConfiguredNetworks();
		for (WifiConfiguration existingConfig : existingConfigs) {
			if (existingConfig.SSID.equals("\"" + SSID + "\"")) {
				return existingConfig;
			}
		}
		return null;
	}
}

Android Wifi控制方法总结