android開發教程之wifi開發示例

2020-04-11 11:52:02

字體：大中小

來源：轉載

供稿：網友

1、 WIFI網卡的狀態
WIFI網卡的狀態信息都以整型變量的形式存放在 android.net.wifi.WifiManager 類中，有以下狀態：
WIFI_STATE_DISABLED
WIFI網卡不可用
WIFI_STATE_DISABLING
WIFI網卡正在關閉
WIFI_STATE_ENABLED
WIFI網卡可用
WIFI_STATE_ENABLING
WIFI網卡正在打開
WIFI_STATE_UNKNOWN
WIFI網卡狀態未知
2、操作WIFI 網卡所需的權限
CHANGE_NETWORK_STATE
允許應用程序改變網絡連接狀態
CHANGE_WIFI_STATE
允許應用程序改變WIFI 連接狀態
ACCESS_NETWORK_STATE
允許應用程序獲取網絡的狀態信息
ACCESS_WIFI_STATE
允許應用程序獲得WIFI 的狀態信息

3、改變WIFI 網卡的狀態
對WIFI 網卡進行操作需要通過對 WifiManager 對象來進行，獲取該對象的方法如下：

復制代碼代碼如下:

WifiManager wifiManager=(WifiManager) Context.getSystemService(Service.WIFI_SERVICE);  

打開WIFI 網卡：

復制代碼代碼如下:

wifiManager.setWifiEnabled(true);

關閉WIFI 網卡

復制代碼代碼如下:

wifiManager.setWifiEnabled(false);

獲取網卡的當前狀態：

復制代碼代碼如下:

wifiManager.getWifiState();

示例代碼：由于Android模擬器不支持wifi操作，所以例子需要在實體手機上運行
AndroidManifest.xml

復制代碼代碼如下:

<?xml version="1.0" encoding="utf-8"?>  
<manifest xmlns:android="http://schemas.android.com/apk/res/android"  
    package="me.bym" android:versionCode="1" android:versionName="1.0">  
    <application android:icon="@drawable/icon" android:label="@string/app_name">  
        <activity android:name=".WifiActivity" 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>  
    <uses-sdk android:minSdkVersion="4" />  
    <!-- 以下是使用wifi訪問網絡所需要的權限 -->  
    <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>  
</manifest> 

Activity

復制代碼代碼如下:

package me.bym;  
import android.app.Activity;  
import android.content.Context;  
import android.net.wifi.WifiManager;  
import android.os.Bundle;  
import android.view.View;  
import android.view.View.OnClickListener;  
import android.widget.Button;  
import android.widget.Toast;  
public class WifiActivity extends Activity {  
    private Button startWifiButton = null;  
    private Button shutdownWifiButton = null;  
    private Button checkStateButton = null;  
    private WifiManager wifiManager = null;  
    private String res = ""; // 用來存放操作結果信息的字符串  
    /** Called when the activity is first created. */  
    @Override  
    public void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
        startWifiButton = (Button) findViewById(R.id.StartWifiButton);  
        shutdownWifiButton = (Button) findViewById(R.id.ShutdownWifiButton);  
        checkStateButton = (Button) findViewById(R.id.CheckStateButton);  
        startWifiButton.setOnClickListener(new StartWifiListener());  
        shutdownWifiButton.setOnClickListener(new ShutdownWifiListener());  
        checkStateButton.setOnClickListener(new CheckStateListener());  
    }  
    class StartWifiListener implements OnClickListener {  
        @Override  
        public void onClick(View v) {  
            wifiManager = (WifiManager) WifiActivity.this  
                    .getSystemService(Context.WIFI_SERVICE);  
            if (wifiManager.setWifiEnabled(true)) {  
                res = "啟動wifi服務成功";  
            } else {  
                res = "啟動wifi服務失敗";  
            }  
            Toast.makeText(WifiActivity.this, res, Toast.LENGTH_SHORT).show();  
        }  
    }  
    class ShutdownWifiListener implements OnClickListener {  
        @Override  
        public void onClick(View v) {  
            wifiManager = (WifiManager) WifiActivity.this  
                    .getSystemService(Context.WIFI_SERVICE);  
            if (wifiManager.setWifiEnabled(false)) {  
                res = "關閉wifi服務成功";  
            } else {  
                res = "關閉wifi服務失敗";  
            }  
            Toast.makeText(WifiActivity.this, res, Toast.LENGTH_SHORT).show();  
        }  
    }  
    class CheckStateListener implements OnClickListener {  
        @Override  
        public void onClick(View v) {  
            wifiManager = (WifiManager) WifiActivity.this  
                    .getSystemService(Context.WIFI_SERVICE);  
            switch (wifiManager.getWifiState()) {  
            case WifiManager.WIFI_STATE_DISABLED:  
                res = "WIFI已關閉";  
                break;  
            case WifiManager.WIFI_STATE_DISABLING:  
                res = "WIFI正在關閉中";  
                break;  
            case WifiManager.WIFI_STATE_ENABLED:  
                res = "WIFI已啟用";  
                break;  
            case WifiManager.WIFI_STATE_ENABLING:  
                res = "WIFI正在啟動中";  
                break;  
            case WifiManager.WIFI_STATE_UNKNOWN:  
                res = "未知WIFI狀態";  
                break;  
            }  
            Toast.makeText(WifiActivity.this, res, Toast.LENGTH_SHORT).show();  
        }  
    }  
}  