Android SDK 提供了 WIFI 开发的相关 API,被保存在 android.net.wifi 和 android.net.wifi.p2p 包下。借助于 Android SDK 提供的相关开发类,可以方便地在 Android 系统的手机上开发基于 WIFI 的应用程序。实例 WIFIDemo 演示了使用 WIFI 进行连接设备搜索并获取相应信息的过程,运行效果如图 1 所示。
图 1 WIFIDemo 运行结果
实例 WIFIDemo 中所使用的布局文件 main.xml 的内容如下:
- <?xml version="1.0" encoding="utf-8"?>
- <ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
- android:id="@+id/mScrollView"
- android:layout_width="fill_parent"
- android:layout_height="wrap_content"
- android:scrollbars="vertical">
- <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent"
- android:orientation="vertical">
- <LinearLayout
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:orientation="horizontal">
- <Button
- android:id="@+id/open_bt"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:text="打开wifi" />
- <Button
- android:id="@+id/close_bt"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:text="关闭wifi" />
- <Button
- android:id="@+id/check_bt"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:text="检查wifi" />
- <Button
- android:id="@+id/search_bt"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:text="扫描wifi" />
- </LinearLayout>
- <TextView
- android:id="@+id/text"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:text="null" />
- </LinearLayout>
- </ScrollView>
实例 WIFIDemo 中 AndroidManifest.xml 文件的代码如下:
- <?xml version="1.0" encoding="utf-8"?>
- <manifest xmlns:android="http://schemas.android.com/apk/res/android"
- package="introduction.android.wifidemo">
- <uses-sdk android:minSdkVersion="10" />
- <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" />
-
- <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>
实例 WIFIDemo 中主 Activity 文件 MainActivity.java 的代码如下:
- package introduction.android.wifidemo;
- import java.util.List;
- import android.R.string;
- import android.app.Activity;
- import android.content.Context;
- import android.net.wifi.ScanResult;
- import android.net.wifi.WifiInfo;
- 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.ScrollView;
- import android.widget.TextView;
- import android.widget.Toast;
- public class MainActivity extends Activity {
- private Button open_bt, close_bt, check_bt, search_bt;
- private TextView textView;
- private WifiManager wifiManager;
- private WifiInfo wifiInfo;
- private ScrollView scrollView;
- private List WifiConfiguration;
- private ScanResult scanResult;
- private List<ScanResult> WifiList;
- private StringBuffer stringBuffer = new StringBuffer();
- /**
- * Called when the activity is first created.
- */
- public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
- setContentView(R.layout.activity_main);
- scrollView = (ScrollView) findViewById(R.id.mScrollView);
- open_bt = (Button) findViewById(R.id.open_bt);
- close_bt = (Button) findViewById(R.id.close_bt);
- check_bt = (Button) findViewById(R.id.check_bt);
- search_bt = (Button) findViewById(R.id.search_bt);
- textView = (TextView) findViewById(R.id.text);
- open_bt.setOnClickListener(new open_btListener());
- close_bt.setOnClickListener(new close_btListener());
- check_bt.setOnClickListener(new check_btListener());
- search_bt.setOnClickListener(new search_btListener());
- }
- class search_btListener implements OnClickListener {
- public void onClick(View v) {
- // TODO Auto-generated method stub
- wifiManager.startScan();
- WifiList = wifiManager.getScanResults();
- wifiInfo = wifiManager.getConnectionInfo();
- if (stringBuffer != null) {
- stringBuffer = new StringBuffer();
- }
- stringBuffer = stringBuffer.append("Wifi名").append(" ").append("Wifi地址").append(" ")
- .append("Wifi频率").append("").append("Wifi信号")
- .append("\n");
- if (WifiList != null) {
- for (int i = 0; i < WifiList.size(); i++) {
- scanResult = WifiList.get(i);
- stringBuffer = stringBuffer.append(scanResult.SSID).append(" ")
- .append(scanResult.BSSID).append(" ")
- .append(scanResult.frequency).append(" ")
- .append(scanResult.level).append("\n");
- textView.setText(stringBuffer.toString());
- }
- stringBuffer = stringBuffer.append
- ("-----------------------------------------------").append("\n");
- textView.setText(stringBuffer.toString());
- stringBuffer = stringBuffer.append("当前Wifi—BSSID").append(":").append(wifiInfo.getBSSID()).append("\n")
- .append("当前wifi—HiddenSSID").append(": ").append(wifiInfo.getHiddenSSID()).append("\n")
- .append("当前Wifi—IpAddress").append(": ").append(wifiInfo.getIpAddress()).append("\n")
- .append("当前Wifi—LinkSpeed").append(": ").append(wifiInfo.getLinkSpeed()).append("\n")
- .append("当前Wifi—MacAddress").append(": ").append(wifiInfo.getMacAddress()).append("\n")
- .append("当前Wifi—Network ID").append(": ").append(wifiInfo.getNetworkId()).append("\n")
- .append("当前Wifi—RSSI").append(": ").append(wifiInfo.getRssi()).append("\n")
- .append("当前Wifi—SSID").append(": ").append(wifiInfo.getSSID()).append("\n")
- .append("-----------------------------------------------").append("\n")
- .append("全部打印出关于本机Wifi信息").append(": ").append
- (wifiInfo.toString());
- textView.setText(stringBuffer.toString());
- }
- //stringBuffer=stringBuffer.append("-----------------------------------------------").append("\n");
- //textView.setText()
- }
- }
- class check_btListener implements OnClickListener {
- public void onClick(View v) {
- // TODO Auto-generated method stub
- wifiManager = (WifiManager) MainActivity.this
- .getSystemService(Context.WIFI_SERVICE);
- System.out.println(wifiManager.getWifiState());
- Toast.makeText(MainActivity.this,
- "当前网卡状态为:" + change(), Toast.LENGTH_SHORT)
- .show();
- }
- }
- class close_btListener implements OnClickListener {
- public void onClick(View v) {
- // TODO Auto-generated method stub
- wifiManager = (WifiManager) MainActivity.this
- .getSystemService(Context.WIFI_SERVICE);
- wifiManager.setWifiEnabled(false);
- System.out.println(wifiManager.getWifiState());
- Toast.makeText(MainActivity.this,
- "当前网卡状态为" + change(), Toast.LENGTH_SHORT)
- .show();
- }
- }
- class open_btListener implements OnClickListener {
- public void onClick(View v) {
- // TODO Auto-generated method stub
- wifiManager = (WifiManager) MainActivity.this.getSystemService(Context.WIFI_SERVICE);
- wifiManager.setWifiEnabled(true);
- System.out.println(wifiManager.getWifiState());
- Toast.makeText(MainActivity.this,
- "当前网卡状态为" + change(), Toast.LENGTH_SHORT)
- .show();
- }
- }
- public String change() {
- String temp = null;
- switch (wifiManager.getWifiState()) {
- case 0:
- temp = "wifi正在关闭ING";
- break;
- case 1:
- temp = "wifi已经关闭";
- break;
- case 2:
- temp = "wifi正在打开ING";
- break;
- case 3:
- temp = "wifi已经打开";
- break;
- default:
- break;
- }
- return temp;
- }
- }