The scenario is the following:
User has connected to a several Wifi profiles, so one can go to Wifi Settings, Saved Networks and see the list of previously connected and saved network configurations.
User has ability to remove a network from the list.
I need to perform some action upon removal of the network from the list. Ho do I intercept the removal action?
Thanks!
I could not find any information on profile management, the only piece of info is that when profile is changed (added/modified/removed) connection state change event occurs. Based on that info I got it working by doing the following:
if (action.equals(WifiManager.SUPPLICANT_STATE_CHANGED_ACTION)) {
SupplicantState ss = intent.getParcelableExtra(WifiManager.EXTRA_NEW_STATE);
if (ss == SupplicantState.DISCONNECTED || ss == SupplicantState.COMPLETED) {
// wifi profile got removed
}
} else if (action.equals(BluetoothDevice.ACTION_ACL_DISCONNECTED)
|| action.equals(BluetoothDevice.ACTION_ACL_CONNECTED)) {
// bluetooth profile got removed
}
Note, no intent is issued when inactive profile got removed.
Related
Background
I've noticed that in WifiManager class there is a function called addNetwork, that might be useful if I want to restore or save networks information (network name AKA SSID, together with the password and the type), so that I could also connect to it.
The problem
I can't find much information about how to do such a thing. I've seen various examples on StackOverflow, and if I target Android API 28 (or below), I indeed succeed to make it add a network and even connect to it.
When targeting Android 29 (Android Q), however, it fails to add the network.
What I've found
Since I'm trying on Pixel 2 with Android Q beta 4, I think that maybe it's because addNetwork is deprecated, so the docs even say so, and that if I target Android Q, it won't work, and indeed it doesn't work:
Compatibility Note: For applications targeting Build.VERSION_CODES.Q
or above, this API will always return -1.
The way it seems it should work up till Android Q (excluding), is by preparing WifiConfiguration and adding it. Later I can also connect to it if I wish. On Android Q, it seems it was replaced by WifiNetworkSuggestion, but it doesn't seem like it's about adding a network at all:
The Network Suggestion object is used to provide a Wi-Fi network for
consideration when auto-connecting to networks. Apps cannot directly
create this object, they must use
WifiNetworkSuggestion.Builder#build() to obtain an instance of this
object.
Apps can provide a list of such networks to the platform using
WifiManager#addNetworkSuggestions(List).
Here's my current code, for pre-Android-Q
#WorkerThread
fun addNetwork(context: Context, networkName: String, networkPassword: String? = null, keyMgmt: Int = WifiConfiguration.KeyMgmt.NONE) {
val wifiManager = context.getSystemService(Context.WIFI_SERVICE) as WifiManager
val conf = WifiConfiguration()
conf.SSID = "\"$networkName\""
conf.preSharedKey = if (networkPassword.isNullOrEmpty()) "" else "\"$networkPassword\""
conf.allowedKeyManagement.set(keyMgmt)
when (keyMgmt) {
WifiConfiguration.KeyMgmt.WPA_PSK -> {
//WPA/WPA2
}
WifiConfiguration.KeyMgmt.IEEE8021X -> {
}
WifiConfiguration.KeyMgmt.WPA_EAP -> {
}
WifiConfiguration.KeyMgmt.NONE -> {
if (networkPassword.isNullOrEmpty()) {
//open network
conf.wepKeys[0] = "\"\""
} else {
//wep
conf.wepKeys[0] = "\"" + networkPassword + "\""
conf.wepTxKeyIndex = 0
conf.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.WEP40)
}
}
}
if (networkPassword.isNullOrEmpty()) {
//open network
conf.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE)
} else {
}
wifiManager.isWifiEnabled = true
while (!wifiManager.pingSupplicant()) {
Log.d("AppLog", "waiting to be able to add network")
}
val networkId = wifiManager.addNetwork(conf)
if (networkId == -1)
Log.d("AppLog", "failed to add network")
else {
wifiManager.enableNetwork(networkId, false)
Log.d("AppLog", "success to add network")
}
}
Seems it requires only these permissions:
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>
But in any case, this works as long as you don't target Android Q (API 29) and above. When you target it, I indeed always get "-1" as a result, meaning it fails.
I've also found an issue on the issue tracker (here and I wrote about it here), telling about someone that needs the API back, but I'm not sure it's about adding a network.
Looking at WifiNetworkSuggestion, I don't see that it has as many things to set as WifiConfiguration via its builder, so this is another reason for why I suspect it's not about adding a network.
But I tried anyway. Here's the code I've tried, for example, to add a normal WPA network:
#WorkerThread
fun addNetworkAndroidQ(context: Context, networkName: String, networkPassword: String? = null) {
val wifiManager = context.getSystemService(Context.WIFI_SERVICE) as WifiManager
val list = ArrayList<WifiNetworkSuggestion>()
val builder = WifiNetworkSuggestion.Builder().setSsid(networkName)
if (!networkPassword.isNullOrEmpty())
builder.setWpa2Passphrase(networkPassword)
list.add(builder.build())
val result = wifiManager.addNetworkSuggestions(list)
if (result == WifiManager.STATUS_NETWORK_SUGGESTIONS_SUCCESS)
Log.d("AppLog", "success")
else Log.d("AppLog", "failed")
}
When running (I gave it my Wifi network details, after making the OS forget about it), it says it succeeded, but nothing occurred on the OS's Wifi settings. The network doesn't exist there with the password I've added. So I really don't get what it did...
After a few long seconds, I've noticed a notification asking me if it's ok to connect to the suggested networks made by the app:
But still when I chose that I accept, it didn't do anything, as before.
I tried to make another POC, thinking I might have done it incorrectly, but then it didn't even show the notification. Since I think this whole behavior is a bug, I've reported about it here.
Not only that, but I've found out that if indeed it is supposed to add a network one way or another, it still has some serious restrictions, such as max added networks (here) and being removed upon uninstall of the app (here)
The questions
How should Android Q be handled exactly? Is there really no API anymore to add a network?
If WifiNetworkSuggestion is not about adding a network, what is it really used for exactly?
Since I'm not familiar enough with the tidbits of adding a network, is my code correct about all possible ways to add a network? I ask this because someone wrote here that people should enable Wifi and make sure pingSupplicant returns true. Is it true? Or would it be enough to just call addNetwork ?
If it's now impossible to add a network using the normal API, is there maybe a solution by using a rooted device instead? Maybe some adb command?
EDIT: Not sure how to do it officially, but using adb, you might be able to add Wifi-networks on Android 11 . Need to check adb shell cmd wifi help .
I stuck with same issue, but somehow I reached a reproducible state for connecting a desired network and I want to share my findings it may helps.
As a summary:
You have to disable all auto connection before applying WifiNetworkSuggestion logic
For more details, Please read the following:
I used the following code (Similar to what you use):
private fun connectUsingNetworkSuggestion(ssid: String, password: String) {
val wifiNetworkSuggestion = WifiNetworkSuggestion.Builder()
.setSsid(ssid)
.setWpa2Passphrase(password)
.build()
// Optional (Wait for post connection broadcast to one of your suggestions)
val intentFilter =
IntentFilter(WifiManager.ACTION_WIFI_NETWORK_SUGGESTION_POST_CONNECTION);
val broadcastReceiver = object : BroadcastReceiver() {
override fun onReceive(context: Context, intent: Intent) {
if (!intent.action.equals(WifiManager.ACTION_WIFI_NETWORK_SUGGESTION_POST_CONNECTION)) {
return
}
showToast("Connection Suggestion Succeeded")
// do post connect processing here
}
}
registerReceiver(broadcastReceiver, intentFilter)
lastSuggestedNetwork?.let {
val status = wifiManager.removeNetworkSuggestions(listOf(it))
Log.i("WifiNetworkSuggestion", "Removing Network suggestions status is $status")
}
val suggestionsList = listOf(wifiNetworkSuggestion)
var status = wifiManager.addNetworkSuggestions(suggestionsList)
Log.i("WifiNetworkSuggestion", "Adding Network suggestions status is $status")
if (status == WifiManager.STATUS_NETWORK_SUGGESTIONS_ERROR_ADD_DUPLICATE) {
showToast("Suggestion Update Needed")
status = wifiManager.removeNetworkSuggestions(suggestionsList)
Log.i("WifiNetworkSuggestion", "Removing Network suggestions status is $status")
status = wifiManager.addNetworkSuggestions(suggestionsList)
}
if (status == WifiManager.STATUS_NETWORK_SUGGESTIONS_SUCCESS) {
lastSuggestedNetwork = wifiNetworkSuggestion
lastSuggestedNetworkSSID = ssid
showToast("Suggestion Added")
}
}
So here are the steps:
Install fresh version / Or remove all suggestion you added before
Make sure that you forgot all surrounding networks so your device won't auto-connect
Add wifi network suggestions list
Go to Wifi Settings to scan networks Or wait until next scan is running
A notification prompt will appear :
6. When you Press "Yes" the system will auto-connect with it via your app and internet will work normally. See the following:
Please note the following:
If you disconnect the network from Wifi Settings (i.e press disconnect bin icon in the following image) your network will be blocked for 24 hours from auto-connect even if you removed the suggested network using wifiManager.removeNetworkSuggestions(listOf(it)) and add it again. And even if you uninstall and install your app again
Unfortunately, this is limitation added by Android System as described here:
If the user uses the Wi-Fi picker to explicitly disconnect from one of the network suggestions when connected to it, then that network is blacklisted for 24 hours. During the blacklist period, that network will not be considered for auto-connection, even if the app removes and re-adds the network suggestion corresponding to the network.
If you uninstall the application while connected to suggested WiFi, the system will close the connection automatically.
In case you have multiple suggestion you can priorities them by using WifiNetworkSuggestion.Builder().setPriority(<Priority Integer>) as mentioned here:
Specify the priority of this network among other network suggestions provided by the same app (priorities have no impact on suggestions by different apps). The higher the number, the higher the priority (i.e value of 0 = lowest priority).
In case you pressed "No" in notification prompt, you can change it from (Settings > Apps & notifications > Special App access > Wi-Fi Control > App name) as described here:
A user declining the network suggestion notification removes the CHANGE_WIFI_STATE permission from the app. The user can grant this approval later by going into the Wi-Fi control menu (Settings > Apps & notifications > Special App access > Wi-Fi Control > App name).
I wish I had answers to all of your questions because I'm currently struggling with similar issues.
After many hours I was finally able to connect to the desired network using this approach:
val wifiNetworkSpecifier = WifiNetworkSpecifier.Builder()
.setSsid(ssid)
.setWpa2Passphrase(passphrase)
.setBssid(mac)
.build()
val networkRequest = NetworkRequest.Builder()
.addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
.setNetworkSpecifier(wifiNetworkSpecifier)
.build()
val connectivityManager = applicationContext.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
connectivityManager?.requestNetwork(networkRequest, ConnectivityManager.NetworkCallback())
You can receive a whole host of events through the ConnectivityManager.NetworkCallback().
Looks like they've added support in Android 11(API 30) for adding network configuration that persists outside of the application scope and is saved as a system network configuration just like it was done with the deprecated WiFiManager method addNetwork. All you need to do is to use ACTION_WIFI_ADD_NETWORKS to show a system dialog that asks a user if he wants to proceed with adding a new Wifi suggestion to the system. This is how we start that dialog:
// used imports
import android.provider.Settings.ACTION_WIFI_ADD_NETWORKS
import android.provider.Settings.EXTRA_WIFI_NETWORK_LIST
import android.app.Activity
import android.content.Intent
import android.net.wifi.WifiNetworkSuggestion
// show system dialog for adding new network configuration
val wifiSuggestionBuilder = WifiNetworkSuggestion.Builder()
.setSsid("network SSID")
.build()
val suggestionsList = arraylistOf(wifiSuggestionBuilder)
val intent = new Intent(ACTION_WIFI_ADD_NETWORKS)
intent.putParcelableArrayListExtra(EXTRA_WIFI_NETWORK_LIST, suggestionsList);
activity.startActivityForResult(intent, 1000)
The dialog looks like this:
And then we just need to handle a result in onActivityResult method like this:
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
if (requestCode == 1000) {
if (resultCode == Activity.RESULT_OK) {
// network succesfully added - User pressed Save
} else if (resultCode == Activity.RESULT_CANCELED) {
// failed attempt of adding network to system - User pressed Cancel
}
}
}
But as I've tested this code on Android devices that have older Android versions(lower then API30) installed I've got a crash every time I want it to show that dialog for adding a new network configuration. This is the crash:
java.lang.RuntimeException: Unable to start activity: android.content.ActivityNotFoundException: No Activity found to handle Intent { act=android.settings.WIFI_ADD_NETWORKS (has extras) }
Looks like the new way is not back-supported out of the box. So, for API30 we can use a new Intent action, for API 28 and below we can still use the old way of adding Networks, but for API29 we have some kind of gray area where I was not able to find a good solution yet. If anyone has an idea what else to do please share it with me. ;)
#Sebastian Helzer's answer works for me. I use java in my application. This may help java users...
WifiNetworkSpecifier wifiNetworkSpecifier = new WifiNetworkSpecifier.Builder()
.setSsid(ssid)
.setWpa2Passphrase(password)
.build();
NetworkRequest networkRequest = new NetworkRequest.Builder()
.addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
.setNetworkSpecifier(wifiNetworkSpecifier)
.build();
ConnectivityManager connectivityManager = (ConnectivityManager)this.getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
connectivityManager.requestNetwork(networkRequest, new ConnectivityManager.NetworkCallback());
I am programming a Wifi Direct game, but have run into a problem with the WifiP2pDevice Status when one user declines the invitation to join the connection.
Phone A initiates connection to Phone B
Phone B status becomes INVITED (as displayed on Phone A)
Phone B decline invitation from Phone A
Phone B status is still INVITED (as displayed on Phone A)
Shouldn't the status be shifted back to AVAILABLE as displayed on Phone A?
I have refreshed the list of Available devices, but the status remains unchanged. even if I restart the app, it still shows the status of Phone B as invited?
Is this supposed to happen based on the API of WifiDirect? or am I missing something?
Edit: More Information
In the BroadcastReciever, when the intent is WifiP2pManager.WIFI_P2P_PEERS_CHANGED_ACTION, then the manager requests the peers using a Fragment that implements a PeerListListener, which just prints a list of available devices and information (including status) of those devices. So when Phone A sends an invitation with manager.connect() it changes the status to INVITED. But if Phone B declines, the status remains as INVITED. And those statuses are triggered on a notifyDataSetChanged(). It is not so much a question about code, but how wifi direct determines and changes statuses of the devices. But I can provide code if needed.
You can cancel the connection if the status is "Invited"
if (fragment.getDevice().status == WifiP2pDevice.AVAILABLE
|| fragment.getDevice().status == WifiP2pDevice.INVITED) {
manager.cancelConnect(channel, new ActionListener() {
#Override
public void onSuccess() {
Toast.makeText(WiFiDirectActivity.this, "Aborting connection",
Toast.LENGTH_SHORT).show();
}
#Override
public void onFailure(int reasonCode) {
Toast.makeText(WiFiDirectActivity.this,
"Connect abort request failed. Reason Code: " + reasonCode,
Toast.LENGTH_SHORT).show();
}
});
}
I am developing an application with NFC and wifi direct. I get the MAC address using NFC and the Wifi Direct to transfer data. I call discoverpeers() and could get success. But there is no callback WIFI_P2P_PEERS_CHANGED_ACTION, the callback comes only when I go to settings and the select wifidirect.
This was discussed in the other question
Can I turn on WiFi-Direct from code? on Android API-14 (ICS)
"I'd like to add that WiFi direct on JB and above (at least on AOSP) is not active all the time - it only appears to be. If you look at listeners for WiFi direct, it turns itself off after some time. It turns itself back on if you open the wifi direct menu, however. You might have to have the host do a peer search or initialize itself in order to be able to be found. Likely a battery saving trick. I have also found that it's blocking, since as it accepts a connection, the entire system will lock up and fail to connect sometimes. (The system invitation) – Mgamerz "
Can anyone suggest the solution for the problem WIFI_P2P_PEERS_CHANGED_ACTION callback is not got and can get only when manually go to settings->wifi->tap on wifidirect
I used two devices Samsung galaxy nexus and nexus 7 both running on 4.2.2
There is no available API to enable wifiP2P but you can invoke method "enableP2p" from android settings 4.0.1
WifiP2pManager manager = (WifiP2pManager) getActivity().getSystemService(Context.WIFI_P2P_SERVICE);
Channel channel = manager.initialize(getActivity(), getActivity().getMainLooper(), null);
try {
Method method1 = manager.getClass().getMethod("enableP2p", Channel.class);
method1.invoke(manager, channel);
//Toast.makeText(getActivity(), "method found",
// Toast.LENGTH_SHORT).show();
} catch (Exception e) {
//Toast.makeText(getActivity(), "method did not found",
// Toast.LENGTH_SHORT).show();
}
To disable wifiP2P use this method
Method method1 = manager.getClass().getMethod("disableP2p", Channel.class);
Not from code. The user has to. That's why the demo has the link to wifi settings in the action bar.
When you call manager.discoverPeers(channel, new WifiP2pManager.ActionListener()
define onFailure and look at the reasonCode. If it's 0, then either the Wifi or WiFi direct is off.
If you look at the WiFi Direct demo app, the WifiDirectBroadcast Reciever, this piece of code looks at whether p2p is enabled specifically
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (WifiP2pManager.WIFI_P2P_STATE_CHANGED_ACTION.equals(action)) {
// UI update to indicate wifi p2p status.
int state = intent.getIntExtra(WifiP2pManager.EXTRA_WIFI_STATE, -1);
if (state == WifiP2pManager.WIFI_P2P_STATE_ENABLED) {
// Wifi Direct mode is enabled
activity.setIsWifiP2pEnabled(true);
} else {
activity.setIsWifiP2pEnabled(false);
activity.resetData();
}
Then when discover peers is called it looks at the variable set by setIsWifiP2pEnabled
thanks user3093354. to continue with your solution, in order to disable the p2p you have to invoke:
Method method1 = manager.getClass().getMethod("disableP2p", Channel.class);
//Try this it may be help you
WifiManager wifiManager = (WifiManager)this.getSystemService(this.WIFI_SERVICE);
wifiManager.setWifiEnabled(true); //True - to enable WIFI connectivity .
//False -disable WIFI connectivity.
//add this permissions in Manifest file :
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE"/>
You can load the wifi driver from a command prompt with the desired concurrency level if you are rooted:
/system/bin/insmod /system/lib/modules/wlan.ko con_mode=3
These are the values:
typedef enum
{
VOS_STA_MODE=0,
VOS_STA_SAP_MODE=1,
VOS_P2P_CLIENT_MODE,
VOS_P2P_GO_MODE,
VOS_MONITOR_MODE,
VOS_FTM_MODE = 5,
VOS_IBSS_MODE,
VOS_P2P_DEVICE_MODE,
VOS_MAX_NO_OF_MODE
} tVOS_CON_MODE;
This is for an Atheros card.
My university has an open wifi access point, however it requires you to enter your e-mail before it allows you to use the web. My problem is that the Wifi is stupid in that it seems to drop my connection and force me to enter my e-mail again every 10 minutes.
I wanted to create my own app that I can use to automatically do this step for me, but I cannot seem to find any documentation for a nice and easy way to detect if a Wifi access point has a browser login page. Is there a way in Android to get this information, or is it just to see if my connection to something is always redirected to 1.1.1.1?
See the "Handling Network Sign-On" section of the HttpUrlConnection documentation:
Some Wi-Fi networks block Internet access until the user clicks through a sign-on page. Such sign-on pages are typically presented by using HTTP redirects. You can use getURL() to test if your connection has been unexpectedly redirected. This check is not valid until after the response headers have been received, which you can trigger by calling getHeaderFields() or getInputStream().
They have a snippet of sample code there. Whether this will cover your particular WiFi AP, I can't say, but it is worth a shot.
Ping an external IP address (like google.com) to see if it responds.
try {
Runtime runtime = Runtime.getRuntime();
Process proc = runtime.exec("ping -c 1 " + "google.com");
proc.waitFor();
int exitCode = proc.exitValue();
if(exitCode == 0) {
Log.d("Ping", "Ping successful!";
} else {
Log.d("Ping", "Ping unsuccessful.");
}
}
catch (IOException e) {}
catch (InterruptedException e) {}
The only downside is this would also indicate that a web login is required when there is simply no internet connectivity on the WiFi access point.
#CommonsWare I believe this is a better answer than opening a UrlConnection and checking the host, since the host doesn't always change even when displaying the redirect page. For example, I tested on a Belkin router and it leaves whatever you typed in the browser as is, but still displays its own page. urlConnection.getUrl().getHost() returns what it should because of this.
I think #FlyWheel is on the right path, but I would use http://clients1.google.com/generate_204 and if you don't get a 204, you know you are behind a captive portal. You can run this in a loop until you do get a 204 in which case you know you are not behind a captive portal anymore.
#FlyWheel wrote: The only downside is this would also indicate that a web login is required when there is simply no internet connectivity on the WiFi access point.
You can solve this by registering a receiver to android.net.conn.CONNECTIVITY_CHANGE. You can check if Wifi is ON and is connected by looking at the Supplicant State of the connection.
Here is a snippet, but I didn't run it:
WifiManager wm = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wm.getConnectionInfo();
SupplicantState suppState = wifiInfo.getSupplicantState();
if (wm.isWifiEnabled()) {
if (suppState == SupplicantState.COMPLETED){
// TODO - while loop checking generate_204 (FlyWheels code)Using intent service.
}
}
I can't remember if the SupplicantState is COMPLETED or ASSOCIATED, you will have to check that. You should use an IntentService for checking the generate_204 since broadcast receivers have a short lifetime.
I used the following code using google's 204 endpoint.
private boolean networkAvailable() {
ConnectivityManager mManager = (ConnectivityManager) getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
if(mManager != null) {
NetworkInfo activeNetwork = mManager.getActiveNetworkInfo();
if(activeNetwork== null || !activeNetwork.isConnectedOrConnecting()){
return false;
}
}
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url("http://clients1.google.com/generate_204")
.build();
try {
Response response = client.newCall(request).execute();
if(response.code() != 204)
return false; // meaning it either responded with a captive html page or did a redirection to captive portal.
return true;
} catch (IOException e) {
return true;
}
}
Many applications including Google Chrome use http://clients1.google.com/generate_204 to verify that the the connection is not locked under captive portal.
The issue might rather be - today at least - that newer Android versions (5.1+?) keep the 3G/4G connection up and running until the wifi login actually leads to a fully functional wifi connection.
I haven't tried it, but maybe with the enum value CAPTIVE_PORTAL_CHECK of NetworkInfos DetailedState one can try to detect such a mode properly?
How do you start the 3G data connection in Android at the same time WiFi is on? I tried
IConnectivityManager.setMobileDataEnabled(enabled); // via reflection
and it works in the emulator, but in my real phone (Droid 2), it briefly turns on then back off again.
From the shell (adb shell), ip link provides the details of the 3G connection:
15: ppp0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 3 link/ppp
However, it is only available when WiFi is off. When WiFi is on and I try to turn it on manually, it complains the ppp0 device doesn't exist.
bash-3.2# ip link set ppp0 up
ip link set ppp0 up
Cannot find device "ppp0"
When I try to list the device, I can't even find it
bash-3.2# ls /dev/ppp*
ls /dev/ppp*
/dev/ppp
As I understand it's not possible to get 3g and WiFi simultaneously connected without modifying Android platform source code (at least versions 2.3 and 4). The main problem is hardcoded priorities of connections defined in frameworks/base/core/res/res/values/config.xml:
<!-- This string array should be overridden by the device to present a list of network
attributes. This is used by the connectivity manager to decide which networks can coexist
based on the hardware -->
<!-- An Array of "[Connection name],[ConnectivityManager connection type],
[associated radio-type],[priority] -->
<!-- ^^^^^^^^^^---------- Connection priority -->
<string-array translatable="false" name="networkAttributes">
<item>"wifi,1,1,1"</item>
<item>"mobile,0,0,0"</item>
<item>"mobile_mms,2,0,2"</item>
<item>"mobile_supl,3,0,2"</item>
<item>"mobile_hipri,5,0,3"</item>
</string-array>
This config.xml is then read by ConnectivityService which is subscribed to connect/disconnect events. And in connect handler it decides what it should do with other connections:
private void handleConnect(NetworkInfo info) {
//------------8-<--------------------------
// if this is a default net and other default is running
// kill the one not preferred
if (mNetAttributes[type].isDefault()) {
if (mActiveDefaultNetwork != -1 && mActiveDefaultNetwork != type) {
if ((type != mNetworkPreference &&
mNetAttributes[mActiveDefaultNetwork].mPriority >
// ^^^^^^^^^ --- From config.xml
mNetAttributes[type].mPriority) ||
// ^^^^^^^^^-------- From config.xml
mNetworkPreference == mActiveDefaultNetwork) {
// don't accept this one
if (DBG) Slog.v(TAG, "Not broadcasting CONNECT_ACTION " +
"to torn down network " + info.getTypeName());
teardown(thisNet);
return;
//------------8-<--------------------------
You could try keeping both active at the same time by modifying your connectivityservice,
but I'd advice against it, since it'll most likely destroy your battery life.
See here if you want to give it a try anyway (and make sure you have a backup, obviously)
If you're trying to connect to a specific machine you can try ConnectivityManager.requestRouteToHost.