android 获取可连接的wifi和wifi信号强度

1、需要在AndroidManifest.xml中添加权限

<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />

根据android系统不同，还需要添加和申请定位权限

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

否则的话，wifiManager.getScanResults()获取不到任何的数据；

2、请先将android设置开启WLAN

private void startScanWifi() {

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

    wifiManager.startScan();

    List<ScanResult> resultList = wifiManager.getScanResults();

    ScanResult scanResult;
    String SSID;
    int rssi;
    int level;
    if (resultList != null && resultList.size() > 0) {
        for (int i = 0; i < resultList.size(); i++) {

            scanResult = resultList.get(i);
            //名称
            SSID = scanResult.SSID;
            //信号强度，得到的值是一个0到-100的区间值，是一个int型数据
            rssi = scanResult.level;
            //信号强度等级，根据强度值，分为6个等级，5最大，表示强度最高
            level = WifiManager.calculateSignalLevel(rssi, 6);
         
        }
    }

}

resultList就是可连接的wifi列表结果

3、获取已连接的wifi

private WifiResultInfo getConnectedWifi() {
    
    WifiResultInfo wifiResultInfo = null;

    WifiInfo wifiInfo = wifiManager.getConnectionInfo();

    if (wifiInfo != null) {
        String ssid = wifiInfo.getSSID();
        int rssi = wifiInfo.getRssi();

        if(ssid.startsWith("\"") && ssid.endsWith("\""))
        {
            ssid = ssid.substring(1, ssid.length() - 1);
        }
   
    }
    return wifiResultInfo;
}