问题
I want to check the presence of some pre-defined open Wifi networks using the Android API (and I want to add them programatically before checking their presence). Here's what I've done. I have created a blank Activity as follows:
WifiManager wifiManager;
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
wifiManager = (WifiManager)getSystemService(Context.WIFI_SERVICE);
myWifis();
}
public void myWifis() {
//Add first network
wcOne = new WifiConfiguration();
wcOne.SSID = "\"" + networkOne + "\"";
wcOne.status = WifiConfiguration.Status.ENABLED;
wcOne.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
//Get Network ID from the wifiManager Object
netOneId = wifiManager.addNetwork(wcOne);
if (networkOneId != -1) {
networkOnePresent = wifiManager.enableNetwork(wcOne.networkId, true);
}
//Add second network
wcTwo = new WifiConfiguration();
wcTwo.SSID = "\"" + networkTwo + "\"";
wcTwo.status = WifiConfiguration.Status.ENABLED;
wcTwo.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
//Get Network ID from the wifiManager Object
netTwoId = mainWifiObj.addNetwork(wcTwo);
if (netTwoId != -1) {
networkTwoPresent = mainWifiObj.enableNetwork(wcTwo.networkId, true);
}
if(networkOnePresent && networkTwoPresent)
createAlert(true);
else
createAlert(false);
wifiManager.disconnect();
wifiManager.removeNetwork(wcOne.networkId);
wifiManager.removeNetwork(wcTwo.networkId);
}
public void createAlert(boolean bothNetworksPresent){
if(bothNetworksPresent){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(this);
alertDialog.setTitle("Both networks present")
.setMessage("Both networks present")
.setCancelable(false)
.setPositiveButton(R.string.ok, new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
}
});
AlertDialog dialog = alertDialog.create();
dialog.show();
}
else{
AlertDialog.Builder alertDialog = new AlertDialog.Builder(this);
alertDialog.setTitle("Not Present")
.setMessage("Not Present")
.setCancelable(false)
.setPositiveButton(R.string.ok, new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
}
});
AlertDialog dialog = alertDialog.create();
dialog.show();
}
}
. I see that both the networks get added to my Wifi list however I get a message "Not present". This is strange because when I go to the Android's Wifi menu, I initially don't see the Wifi being present but when I hit scan I see those networks.
I want to check if I can connect to both the Wifi hotspots. I want connect to one hotspot disconnect and then connect to another one. How do I do this?
Edit:
I also note that the Wifi networks that I add are not being removed from the list. Is there any particular reason for this?
Edit 2
I even tried changing my entire code to listen to BroadcastReceiver for scan and connection separately and that too after certain intervals of time. So here's what I did:
WifiManager wifiManager;
private final Handler mHandler = new Handler();
public final String TAG = "myWifiScanner";
boolean isOneAdded = false, isTwoAdded = false, isThreeAdded = false;
boolean isOneConnected = false, isTwoConnected = false, isThreeConnected = false;
boolean isOneEnabled = false, isTwoEnabled = false, isThreeEnabled = false;
IntentFilter iFScan, iFConnect;
List<ScanResult> scanList;
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
wifiManager = (WifiManager)getSystemService(Context.WIFI_SERVICE);
checkConnections();
}
private void receiverMethod(){
//iFScan = new IntentFilter();
iFConnect = new IntentFilter();
iFConnect.addAction(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION);
iFConnect.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION);
//registerReceiver(scanR, iFScan);
registerReceiver(connectR, iFConnect);
wifiManager.startScan();
Log.d(TAG, "\nScan started\n");
}
private final BroadcastReceiver connectR = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if(action.equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)){
if(intent.getBooleanExtra(WifiManager.EXTRA_SUPPLICANT_CONNECTED, false)){
String ssid = null;
ConnectivityManager connManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if(netInfo.isConnected()){
final WifiManager wifiManager = (WifiManager)context.getSystemService(Context.WIFI_SERVICE);
final WifiInfo connectionInfo = wifiManager.getConnectionInfo();
if(connectionInfo != null && !TextUtils.isEmpty(connectionInfo.getSSID())){
ssid = connectionInfo.getSSID();
if(isOneAdded && ssid.equals(networkOne)){
isOneConnected = true;
Log.d(TAG, "One Connected\n");
}
if(isTwoAdded && ssid.equals(networkTwo)){
isTwoConnected = true;
Log.d(TAG, "Two Connected\n");
}
if(isThreeAdded && ssid.equals(networkThree)){
isThreeConnected = true;
Log.d(TAG, "Three Connected\n");
}
}
}
}
if(action.equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)){
scanList = wifiManager.getScanResults();
for(int i = 0; i < scanList.size(); i++){
if(isOneAdded && scanList.get(i).toString().contains(networkOne)){
isOneEnabled = true;
Log.d(TAG, "One Enabled\n");
}
if(isTwoAdded && scanList.get(i).toString().contains(networkTwo)){
isTwoEnabled = true;
Log.d(TAG, "Two Enabled\n");
}
if(isThreeAdded && scanList.get(i).toString().contains(networkThree)){
isThreeEnabled = true;
Log.d(TAG, "Three Enabled\n");
}
}
}
}
};
public final Runnable addNetworkOne = new Runnable() {
@Override
public void run() {
//Add first network
wcOne = new WifiConfiguration();
wcOne.SSID = "\"" + networkOne + "\"";
wcOne.status = WifiConfiguration.Status.ENABLED;
wcOne.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
//Get Network ID from the wifiManager Object
netOneId = wifiManager.addNetwork(wcOne);
if (networkOneId != -1) {
networkOnePresent = wifiManager.enableNetwork(wcOne.networkId, true);
}
}
isOneAdded = true
receiverMethod();
};
public final Runnable addNetworkTwo = new Runnable() {
@Override
public void run() {
//Add second network
wcTwo = new WifiConfiguration();
wcTwo.SSID = "\"" + networkTwo + "\"";
wcTwo.status = WifiConfiguration.Status.ENABLED;
wcTwo.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
//Get Network ID from the wifiManager Object
netTwoId = wifiManager.addNetwork(wcTwo);
if (netTwoId != -1) {
networkTwoPresent = wifiManager.enableNetwork(wcTwo.networkId, true);
}
}
isTwoAdded = true
receiverMethod();
};
public final Runnable addNetworkThree = new Runnable() {
@Override
public void run() {
//Add three network
wcThree = new WifiConfiguration();
wcThree.SSID = "\"" + networkThree + "\"";
wcThree.status = WifiConfiguration.Status.ENABLED;
wcThree.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
//Get Network ID from the wifiManager Object
netThreeId = wifiManager.addNetwork(wcTwo);
if (netThreeId != -1) {
networkThreePresent = wifiManager.enableNetwork(wcThree.networkId, true);
}
}
isThreeAdded = true
receiverMethod();
};
public final Runnable areAllWifisPresent = new Runnable() {
@Override
public void run() {
if(isOneEnabled && isTwoEnabled && isThreeeEnabled){
if(isOneConnected && isTwoConnected && isThreeConnected){
Log.d(TAG, "All three Wifis are present.");
}
}
};
public void checkConnections() {
mHandler.postDelayaed(addNetworkOne, 10*1000);
mHandler.postDelayed(addNetworkTwo, 20*1000);
mHandler.postDelayed(addNetworkThree, 30*1000);
mHandler.postDelayed(areAllWifisPresent, 40*1000);
//wifiManager.disconnect();
//wifiManager.removeNetwork(wcOne.networkId);
//wifiManager.removeNetwork(wcTwo.networkId);
//wifiManager.removeNetwork(wcThree.networkId);
}
**Edit 3: ** I also noticed that the receiver for checking if Wifi is connected is not getting called. I am not sure why.
回答1:
Please change your MyWifi() method to
public void myWifis() {
WifiManager wifiManager = (WifiManager) this.getSystemService(Context.WIFI_SERVICE);
wifiManager.setWifiEnabled(true);
//Add first network
wcOne = new WifiConfiguration();
wcOne.SSID = "\""+SSID+"\"";
wcOne.status = WifiConfiguration.Status.ENABLED;
wcOne.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
//Get Network ID from the MainWiFi Object
int netOneId = mainWifiObj.addNetwork(wcOne);
boolean networkOnePresent = false;
//this way we will enable wifi network.
List<WifiConfiguration> list = wifiManager.getConfiguredNetworks();
for( WifiConfiguration i : list ) {
Log.d("wifi", "wifi SSID is = "+i.SSID);
if(i.SSID != null && i.SSID.equals("\"" + SSID + "\"")) {
wifiManager.disconnect();
networkOnePresent = wifiManager.enableNetwork(i.networkId, true);
wifiManager.reconnect();
Log.d("wifi", "net id is = "+netOneId);
break;
}
}
if(networkOnePresent)
createAlert(true);
else
createAlert(false);
}
It will work.
来源：https://stackoverflow.com/questions/25075343/how-do-i-connect-to-multiple-wifi-networks-one-after-the-another-programatically