android 之WIFI操作

wifi网卡的状态
1.WIFI_STATE_DISABLED:WIFI网卡不可用
2.WIFI_STATE_DISABLING:WIFI网卡正在关闭
1.WIFI_STATE_EWNABLED:WIFI网卡可用
1.WIFI_STATE_ENABLING:WIFI网卡正在打开
1.WIFI_STATE_UNKNOWN:未知网卡状态

改变WIFI网卡的状态
对WIFI网卡进行操作需要通过WifiManager对象进行，获取该对象的方法如下：
WifiManger wifiManger = (WifiManger)Context.getSystemService(Service.WIFI_SERVICE); //得到系统服务
打开WIFI网卡
wifiManger.setWifiEnabled(true);
打开WIFI网卡
wifiManger.setWifiEnabled(false);
获取网卡当前状态

wifiManger.getWifiState();

android在操作wifi之前需要给app赋予权限：

在AndroidManifest.xml文件中加入红色的代码

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.yx.wificontrol"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="18" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.yx.wificontrol.WifiControlActivity"
            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>
<!-- 添加wifi网络需要的权限 -->
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE"/>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
</manifest>

代码比较简单，WifiControlActivity.java文件

package com.yx.wificontrol;

import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

public class WifiControlActivity extends Activity {

    private Button startWifi;
    private Button stopWifi;
    private Button seeWifi;
    private WifiManager wifiManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_wifi_control);
        startWifi = (Button) findViewById(R.id.startWifi);
        stopWifi = (Button) findViewById(R.id.stopWifi);
        seeWifi = (Button) findViewById(R.id.seeWifi);
        startWifi.setOnClickListener(new StartWifiListener());
        stopWifi.setOnClickListener(new StopWifiListener());
        seeWifi.setOnClickListener(new SeeWifiListener());
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.wifi_control, menu);
        return true;
    }
    
    class StartWifiListener implements OnClickListener{
        @Override
        public void onClick(View v) {
            System.out.println("StartWifiListener");
            //Toast.makeText(WifiControlActivity.this, "当前网卡状态："+wifiManager.getWifiState(), Toast.LENGTH_LONG);
            wifiManager = (WifiManager) WifiControlActivity.this.getSystemService(Context.WIFI_SERVICE);
            wifiManager.setWifiEnabled(true);
            System.out.println("wifi 状态："+wifiManager.getWifiState());
            Toast.makeText(WifiControlActivity.this, "当前网卡状态："+wifiManager.getWifiState(), Toast.LENGTH_LONG).show();
        }
    }
    
    class StopWifiListener implements OnClickListener{
        @Override
        public void onClick(View v) {
            System.out.println("StopWifiListener");
            //Toast.makeText(WifiControlActivity.this, "当前网卡状态："+wifiManager.getWifiState(), Toast.LENGTH_SHORT);
            wifiManager = (WifiManager) WifiControlActivity.this.getSystemService(Context.WIFI_SERVICE);
            wifiManager.setWifiEnabled(false);
            System.out.println("wifi 状态："+wifiManager.getWifiState());
            Toast.makeText(WifiControlActivity.this, "当前网卡状态："+wifiManager.getWifiState(), Toast.LENGTH_SHORT).show();
        }
    }
    
    class SeeWifiListener implements OnClickListener{
        @Override
        public void onClick(View v) {
            System.out.println("SeeWifiListener");
            wifiManager = (WifiManager) WifiControlActivity.this.getSystemService(Context.WIFI_SERVICE);
            System.out.println("wifi 状态："+wifiManager.getWifiState());
            Toast.makeText(WifiControlActivity.this, "当前网卡状态："+wifiManager.getWifiState(), Toast.LENGTH_LONG).show();
            
        }
    }

}
顺便贴出布局文件

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".WifiControlActivity" >

    <Button
        android:id="@+id/startWifi"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="启动wifi网卡" />
    <Button
        android:id="@+id/stopWifi"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/startWifi"
        android:text="关闭wifi网卡" />
    <Button
        android:id="@+id/seeWifi"
        android:layout_below="@id/stopWifi"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="查看wifi网卡状态" />

</RelativeLayout>