WifiManager.NETWORK_STATE_CHANGED_ACTION 广播在Android9.0还有效，Android10.0已经无效了。

WifiInfo wifiInfo = intent.getParcelableExtra(WifiManager.EXTRA_WIFI_INFO);
String bssid = intent.getStringExtra(WifiManager.EXTRA_BSSID);
解决办法：
 android10如果要用到wifi相关的api时要引用ACCESS_FINE_LOCATION 或 ACCESS_COARSE_LOCATION权限。
 添加权限：
 
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
使用方法：
 
public static String getWIFISSID(Activity activity) {
    String ssid = "unknown id";
    if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.O || Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
        WifiManager mWifiManager = (WifiManager) activity.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
        assert mWifiManager != null;
        WifiInfo info = mWifiManager.getConnectionInfo();
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {
            return info.getSSID();
        } else {
            return info.getSSID().replace("\"", "");
    } else if (Build.VERSION.SDK_INT == Build.VERSION_CODES.O_MR1) {
        ConnectivityManager connManager = (ConnectivityManager) activity.getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
        assert connManager != null;
        NetworkInfo networkInfo = connManager.getActiveNetworkInfo();
        if (networkInfo.isConnected()) {
            if (networkInfo.getExtraInfo() != null) {
                return networkInfo.getExtraInfo().replace("\"", "");
    return ssid;
原文链接：
 Android10的WIFI 名称读取为空解决