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Connection to specific WiFi if already have connection to another

I've been fighting like a fish for two days already, and I can not find a solution. I tried this code but it through time worked on Android 5(Lollipop) and didn't work at 7.1.1.(Nougat) I have another Scenario where phone loses connection and after this, it needs to return to the old Wifi.
public void setWifiConnection1(View view){
WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
WifiConfiguration wc = new WifiConfiguration();
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
wc.SSID = "\"NETWORK_NAME\"";
wc.preSharedKey = "\"PASSWORD\"";
wc.status = WifiConfiguration.Status.ENABLED;
wc.allowedProtocols.set(WifiConfiguration.Protocol.RSN);
wc.allowedProtocols.set(WifiConfiguration.Protocol.WPA);
wc.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.WPA_PSK);
wc.allowedPairwiseCiphers.set(WifiConfiguration.PairwiseCipher.CCMP);
wc.allowedPairwiseCiphers.set(WifiConfiguration.PairwiseCipher.TKIP);
wc.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.WEP40);
wc.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.WEP104);
wc.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.CCMP);
wc.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.TKIP);
wc.priority = 999999;
wifiManager.setWifiEnabled(true);
int netId = wifiManager.addNetwork(wc);
if (netId == -1) {
netId = getExistingNetworkId(wc.SSID);
}
wifiManager.disconnect();
wifiManager.enableNetwork(netId, true);
wifiManager.reconnect();
}
private int getExistingNetworkId(String SSID) {
WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
List<WifiConfiguration> configuredNetworks = wifiManager.getConfiguredNetworks();
if (configuredNetworks != null) {
for (WifiConfiguration existingConfig : configuredNetworks) {
if (existingConfig.SSID.equals(SSID)) {
return existingConfig.networkId;
}
}
}
return -1;
}

wifiManager.setWifiEnabled(true);
You can't execute your code right after this line. You should do a wifiManager.isWifiEnabled() check and subscribe to a broadcast if it's disabled.
Next...
wifiManager.disconnect();
wifiManager.enableNetwork(netId, true);
wifiManager.reconnect();
This part is very odd: why do you disconnect ? Be aware that most of WifiManager operations are asynchronous so that's why you observe different results each time - real "disconnect" may occur after you've tried to enable your desired network.
You can always get inspiration from system API: https://android.googlesource.com/platform/frameworks/base/+/android-8.0.0_r30/wifi/java/android/net/wifi/WifiManager.java#2773
So correct sequence is:
wifiManager.addNetwork(...);
wifiManager.enableNetwork(netId, true);
wifiManager.saveConfiguration();
wifiManager.reconnect();
But if you are allowed to do so, it's more convenient to use system API directly.

How to get device hotspot SSID programmatically in Android?

I'm struggling to find a way to find hotspot ssid of the device, all solutions which I found were returning Wi-Fi name to which device is connected while I want to find the hotspot name, which the device created.
getting wifi name
public static String getWifiName(Context context) {
WifiManager manager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
if (manager.isWifiEnabled()) {
WifiInfo wifiInfo = manager.getConnectionInfo();
if (wifiInfo != null) {
NetworkInfo.DetailedState state = WifiInfo.getDetailedStateOf(wifiInfo.getSupplicantState());
if (state == NetworkInfo.DetailedState.CONNECTED || state == NetworkInfo.DetailedState.OBTAINING_IPADDR) {
return wifiInfo.getSSID();
}
}
}
return null;
}

Reconnecting to a WiFi Network after disconnecting from it Programatically

I got disconnected from a WiFi network Programatically using
WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
wifi.disconnect();
DisconnectWifi discon = new DisconnectWifi();
registerReceiver(discon, new IntentFilter(WifiManager.SUPPLICANT_STATE_CHANGED_ACTION));
public class DisconnectWifi extends BroadcastReceiver {
#Override
public void onReceive(Context c, Intent intent) {
WifiManager wifi = (WifiManager) c.getSystemService(Context.WIFI_SERVICE);
if(!intent.getParcelableExtra(WifiManager.EXTRA_NEW_STATE).toString().equals(SupplicantState.SCANNING))
wifi.disconnect();
}
}
But I am not able to reconnect to the same network again. I tried reconnecting by using:
WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
wifi.reconnect();
but was not able to connect. How can I now reconnect to WiFi Network?
Thanks,

So the complete, simplified solution would look something like this:
WifiConfiguration wifiConfig = new WifiConfiguration();
wifiConfig.SSID = String.format("\"%s\"", ssid);
wifiConfig.preSharedKey = String.format("\"%s\"", key);
WifiManager wifiManager = (WifiManager)getSystemService(WIFI_SERVICE);
//remember id
int netId = wifiManager.addNetwork(wifiConfig);
wifiManager.disconnect();
wifiManager.enableNetwork(netId, true);
wifiManager.reconnect();
Hope it Helps You!!

Can we make an android app which works only when we connect to a specific Wi-fi Network?

I want to know whether we can make an android app which works only when we connect to a specific wi-fi Network?
All help is much appreciated! I'm all out of ideas here. Thank you.

boolean onRightNetwork() {
WifiManager wifiManager = (WifiManager) App.getContext()
.getSystemService(App.getContext().WIFI_SERVICE);
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
return wifiInfo.getSSID().equals(NETWORK_NAME);
}
Run that in onResume, and just pop up a screen that says to connect to the right network if it returns false. You may also want to register a broadcast receiver to listen for wifi connect/disconnect events and perform this check as needed there as well.

You can write your own logic for that in launcher Activity.
WifiManager wifiMgr = (WifiManager) getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiMgr.getConnectionInfo();
String name = wifiInfo.getSSID();
above code is to get name of currently connected network name, you can make condition if it matches your predefined name, allow user to use your application.

Try this:
WifiManager wifiManager = (WifiManager)getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
wifiInfo.getSSID();
After getting the SSID, match it with your desired one. If the condition is met, then do whatever you want.

You could try something like this:
ConnectivityManager connManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if (!mWifi.isConnected()) {
// exit app here
}
make sure You have proper permission in Your AndroidManifest.xml
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
Related answer here: https://stackoverflow.com/a/3841407/3693617

How can I find wifi speed in Android and how can I display wifi speed in TextView?

To find wifi speed I used this code:
WifiManager wifiManager = (WifiManager)this.getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
if (wifiInfo != null) {
int linkSpeed = wifiInfo.getLinkSpeed(); //measured using WifiInfo.LINK_SPEED_UNITS
//txtSpeed.setText(linkSpeed);
}
I want to display the speed in my TextView. How can I do this?

Try This ::
TextView speedcount;
String s = Integer.toString(linkSpeed);
speedcount = (TextView)findViewById(R.id.textview);
speedcount.setText(s);

txtSpeed.setText(""+linkSpeed); or textSpeed.setText(Integer.toString(linkSpeed));. Make sure txtSpeed is instantiated properly.