java - wifi连接后如何显示按钮？

Question

在我的应用程序中，我以编程方式连接到 wifi。有没有办法让我在 wifi 连接时显示一个按钮？

Answer 1

您可以使用此问题来告诉您是否已连接到 wifi。一旦你知道你是你，你就可以像往常一样显示你的按钮。

因此，您的代码（取自 Jason Knight 的回答）将是：

ConnectivityManager connManager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);

if (mWifi.isConnected()) {
    // show button 
}

Answer 2

You will need to implement a BroadcastReceiver to listen for network state changes.

private final BroadcastReceiver mWifiScanReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context c, Intent intent) {
        if (intent.getAction() == WifiManager.NETWORK_STATE_CHANGED_ACTION) {
            Bundle extras = Intent.getExtras();
            NetworkInfo ni = extras.get(EXTRA_NETWORK_INFO);
            if (ni.getState() == State.CONNECTED) {
                //show button
            } else {
                //hide button
            }
        } else if (intent.getAction() == WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION) {
            Bundle extras = Intent.getExtras();
            SupplicantState ss = extras.get(EXTRA_NEW_STATE);
            if (ss.getState() == COMPLETED) {
                //show button, note we may not have an IP address yet
            } else {
                //hide button
            }
            SupplicantState.COMPLETED
        }
    }
};

and, somewhere in the OnCreate() method of the Activitys that will display the button:

mWifiManager = (WifiManager)getSystemService(Context.WIFI_SERVICE);

//to listen to all network state changes (cell and wifi)
registerReceiver(mWifiScanReceiver, new IntentFilter(WifiManager.NETWORK_STATE_CHANGED_ACTION));

//to listen specifically to wifi changes
registerReceiver(mWifiScanReceiver, new IntentFilter(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION));