Develop Reference

How to handle Cancel button on the dialog shown by NetworkRequest.Builder().setNetworkSpecifier

I'm trying to connect to WiFi AP provided by peripheral device with NetworkRequest.Builder().setNetworkSpecifier().
I succeeded to connect but I still have a problem in failure case.
fun connectPeerWifiNetworkFlow(peerSpecifier: NetworkSpecifier) = callbackFlow {
val request = NetworkRequest.Builder()
.addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
.removeCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
.setNetworkSpecifier(peerSpecifier)
.build()
val networkCallback = object : ConnectivityManager.NetworkCallback() {
override fun onAvailable(network: Network) {
super.onAvailable(network)
trySend(network)
}
override fun onUnavailable() {
super.onUnavailable()
trySend(null)
}
}
connectivityManager.requestNetwork(request, networkCallback)
awaitClose {
connectivityManager.unregisterNetworkCallback(networkCallback)
}
}
This code worked fine but I had a problem when no AP was found.
A result dialog will be shown if no AP has not been found.
Any callback wasn't called even if "Cancel" button was tapped on the dialog.
How can I handle "Cancel" behavior?
[Dialog shown when no AP was found][1]
[1]: https://i.stack.imgur.com/g0W1e.png**strong text**

Using CompanionDeviceManager to read the devices information

I am using BluetoothLeScanner to scan for BLE devices and get a list of objects representing the devices to show inside my app (not connecting to any of them).
I am interested in doing the same, but using the CompanionDeviceManager now. Its callback CompanionDeviceManager.Callback.onDeviceFound(chooserLauncher: IntentSender?) unfortunately does not return any human readable form of found devices... the closest it gets is the IntentSender.writeToParcel method, but I am not sure how to use it in this situation.
I am not constrained to use the CompanionDeviceManager but I wanted to follow the OS version specific guidelines, we are supposed to use CompanionDeviceManager for Bluetooth devices scanning starting from API 26, but it seems useless in my case... so is there any way to get devices data from that callback, or should I just ditch it and stay with BluetoothLeScanner for all OS versions?

Late answer but it might help someone else. You can create a bluetooth device picker in combination with ActivityResultContracts.StartIntentSenderForResult() in order to get the BluetoothDevice. From there you will have access to all the device info that you need. Recent changes added some Android 12 permissions like android.permission.BLUETOOTH_CONNECT. Your mileage may vary.
val context = LocalContext.current
// Get the device manager instance
val deviceManager: CompanionDeviceManager by lazy {
ContextCompat.getSystemService(
context,
CompanionDeviceManager::class.java
) as CompanionDeviceManager
}
// Create a filter of your choice. Here I just look for specific device names
val deviceFilter: BluetoothDeviceFilter by lazy {
BluetoothDeviceFilter.Builder()
.setNamePattern(Pattern.compile(supportedDevices))
.build()
}
// Create a pairing request with your filter from the last step
val pairingRequest: AssociationRequest = AssociationRequest.Builder()
.addDeviceFilter(deviceFilter)
.build()
// Create a picker for discovered bluetooth devices
val bluetoothDevicePicker = rememberLauncherForActivityResult(
contract = ActivityResultContracts.StartIntentSenderForResult(),
onResult = {
val device: BluetoothDevice? =
it.data?.getParcelableExtra(CompanionDeviceManager.EXTRA_DEVICE)
try {
// Now that you have the desired device, do what you need to with it
device?.apply {
when {
name?.matches(Regex(firstDevicePattern)) == true -> {
Log.i(TAG, "${this.name} connected")
onFirstDeviceDiscovered(device)
}
name?.matches(Regex(secondDevicePattern)) == true -> {
Log.i(TAG, "${this.name} connected")
onSecondDeviceDiscovered(device)
}
}
}
} catch (e: SecurityException) {
e.printStackTrace()
//TODO: handle the security exception (this is possibly a bug)
// https://issuetracker.google.com/issues/198986283
}
}
)
// A utility function to centralize calling associate (optional)
val associateDevice: (AssociationRequest) -> Unit = { request ->
// Attempt to associate device(s)
deviceManager.associate(
request,
object : CompanionDeviceManager.Callback() {
override fun onDeviceFound(chooserLauncher: IntentSender) {
val sender = IntentSenderRequest.Builder(chooserLauncher)
.build()
bluetoothDevicePicker.launch(sender)
}
override fun onFailure(error: CharSequence?) {
//TODO: handle association failure
}
}, null
)
}

Stay connected on a network without Internet

I'm trying to connect to a Wi-Fi hotspot on Android 10 which has no available Internet connection. The problem is that as soon as I'm connected and the device detects there's no connection, it goes back to another connection with Internet available.
After looking up what I can do I've found this piece of code which supposedly forces staying:
val manager = applicationContext.getSystemService(Context.WIFI_SERVICE) as WifiManager
val mWifiLock: WifiManager.WifiLock = manager.createWifiLock(WifiManager.WIFI_MODE_FULL, "wifiLock")
if (! mWifiLock.isHeld) {
mWifiLock.acquire()
}
Unfortunately, that code is deprecated and doesn't work anymore. So far, the only working solutions I've found was disabling the other networks. I've also found other threads on StackOverflow with the exact same problem, but those were created 1+ years ago so I figured I might ask this again.
Does anyone know of an updated way I can stay connected to this network?
This is the code I use for connecting to the hotspot btw:
val wifiNetworkSpecifier = WifiNetworkSpecifier.Builder()
.setSsid(ssid)
.setWpa2Passphrase(pass)
.build()
val wifiRequest = NetworkRequest.Builder()
.addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
.removeCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
.setNetworkSpecifier(wifiNetworkSpecifier)
.build()
val connectivity = applicationContext.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
val networkCallback = object : ConnectivityManager.NetworkCallback() {
override fun onUnavailable() {
super.onUnavailable()
}
override fun onLosing(network: Network, maxMsToLive: Int) {
super.onLosing(network, maxMsToLive)
listener(false)
}
override fun onLost(network: Network) {
super.onLost(network)
listener(false)
}
override fun onAvailable(network: Network) {
super.onAvailable(network)
connectivity?.bindProcessToNetwork(network)
//Code to force-stay
listener(true)
}
}
connectivity?.requestNetwork(wifiRequest, networkCallback)

Combine WiFi Specifier and Suggestion APIs on Android Q

I am building an app where the connection to a 2nd device is the essence. Therefore, I used the WifiNetworkSpecifier API. However, the application must be able to automatically reconnect to the target network once the users leave and return to the Wi-Fi perimeter. Thus, I used the WifiNetworkSuggestion API. However, I am experiencing several issues there:
Once I get connected to the SSID using the specifier API and I confirm the push notification generated by the suggestion API, the suggestion API does not seem to work until I manually disconnect from the SSID (unregister network callback previously assigned to the specifier request) or kill the application.
If there is another network present in the perimeter which the user previously connected to by using the OS Wi-Fi manager (a hotspot, for instance), Android will prioritize this network, hence the suggestion API for my application would never auto-reconnect to the wanted and accessible SSID.
From my experience and understanding (which might be wrong) so far, it seems like we have to manually unregister the network callback previously assigned to the specifier request, or kill the application, and let the suggestion API to do its thing until it can work properly. This might be problematic if there are other networks (which the user previously connected to by using the OS Wi-Fi manager) present in the perimeter. In this case, we'd never auto-reconnect to the SSID defined by the application and the suggestion API would never work.
The question is: how to combine those two APIs to be able to connect to an SSID, yet auto-reconnect, without doing such ugly hacks as manually disconnecting the user, or killing the application, which also doesn't give us any guarantees?
In my opinion, this whole new implementation with the new network APIs is not done well, it's creating a lot of issues and restrictions for developers, or at least it's poorly documented.
Here's the code used for making the requests. Note that the device I'm connecting to does not have actual internet access, it's just used as a p2p network.
#RequiresApi(api = Build.VERSION_CODES.Q)
private fun connectToWiFiOnQ(wifiCredentials: WifiCredentials, onUnavailable: () -> Unit) {
val request = NetworkRequest.Builder()
.addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
.removeCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
.setNetworkSpecifier(createWifiNetworkSpecifier(wifiCredentials))
.build()
networkCallback = object : ConnectivityManager.NetworkCallback() {
override fun onAvailable(network: Network) {
super.onAvailable(network)
connectivityManager.bindProcessToNetwork(network)
}
override fun onUnavailable() {
super.onUnavailable()
onUnavailable.invoke()
}
}
networkCallback?.let {
addNetworkSuggestion(wifiCredentials)
connectivityManager.requestNetwork(request, it)
}
}
#RequiresApi(api = Build.VERSION_CODES.Q)
private fun addNetworkSuggestion(wifiCredentials: WifiCredentials) {
wifiManager.addNetworkSuggestions(listOf(createWifiNetworkSuggestion(wifiCredentials))).apply {
if (this != WifiManager.STATUS_NETWORK_SUGGESTIONS_SUCCESS) {
if (this == WifiManager.STATUS_NETWORK_SUGGESTIONS_ERROR_ADD_EXCEEDS_MAX_PER_APP) {
wifiManager.removeNetworkSuggestions(emptyList())
addNetworkSuggestion(wifiCredentials)
}
}
}
suggestionBroadcastReceiver?.let { context.unregisterReceiver(it) }
suggestionBroadcastReceiver = object : BroadcastReceiver() {
override fun onReceive(context: Context?, intent: Intent?) {
if (intent?.action != WifiManager.ACTION_WIFI_NETWORK_SUGGESTION_POST_CONNECTION)
return
// Post connection processing..
}
}
context.registerReceiver(
suggestionBroadcastReceiver, IntentFilter(WifiManager.ACTION_WIFI_NETWORK_SUGGESTION_POST_CONNECTION)
)
}
#RequiresApi(api = Build.VERSION_CODES.Q)
private fun createWifiNetworkSpecifier(wifiCredentials: WifiCredentials): WifiNetworkSpecifier {
return when (wifiCredentials.authenticationType.toLowerCase()) {
WifiCipherType.NOPASS.name.toLowerCase() -> WifiNetworkSpecifier.Builder()
.setSsid(wifiCredentials.networkSSID)
.setIsHiddenSsid(wifiCredentials.isSSIDHidden)
.build()
WifiCipherType.WPA.name.toLowerCase() -> WifiNetworkSpecifier.Builder()
.setSsid(wifiCredentials.networkSSID)
.setWpa2Passphrase(wifiCredentials.password)
.setIsHiddenSsid(wifiCredentials.isSSIDHidden)
.build()
else -> WifiNetworkSpecifier.Builder()
.setSsid(wifiCredentials.networkSSID)
.setIsHiddenSsid(wifiCredentials.isSSIDHidden)
.build()
}
}
#RequiresApi(api = Build.VERSION_CODES.Q)
private fun createWifiNetworkSuggestion(wifiCredentials: WifiCredentials): WifiNetworkSuggestion {
return when (wifiCredentials.authenticationType.toLowerCase()) {
WifiCipherType.NOPASS.name.toLowerCase() -> WifiNetworkSuggestion.Builder()
.setSsid(wifiCredentials.networkSSID)
.setIsHiddenSsid(wifiCredentials.isSSIDHidden)
.build()
WifiCipherType.WPA.name.toLowerCase() -> WifiNetworkSuggestion.Builder()
.setSsid(wifiCredentials.networkSSID)
.setWpa2Passphrase(wifiCredentials.password)
.setIsHiddenSsid(wifiCredentials.isSSIDHidden)
.build()
else -> WifiNetworkSuggestion.Builder()
.setSsid(wifiCredentials.networkSSID)
.setIsHiddenSsid(wifiCredentials.isSSIDHidden)
.build()
}
}

Calling the suggestion API in onAvailable works for me. That way the user doesn't see two popups at the same time either.
val networkCallback = object : ConnectivityManager.NetworkCallback() {
override fun onAvailable(network: Network) {
connectivityManager.bindProcessToNetwork(network)
addNetworkSuggestion(wifiCredentials)
}
}

How make a SMB connection through Network object in Android?

I'm trying to make a SMB (Samba) connection to get a list of files and download them with the SMBClient of smbj library.
To that I have to connect to a specific network and use that class, but in Android Q I have to change the way to connect to the wireless, like this:
val wifiNetworkSpecifier: WifiNetworkSpecifier = WifiNetworkSpecifier.Builder().apply {
setSsid(ssid)
setWpa2Passphrase(password)
}.build()
val networkRequest: NetworkRequest = NetworkRequest.Builder().apply {
addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
removeCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED)
setNetworkSpecifier(wifiNetworkSpecifier)
}.build()
val networkCallback: ConnectivityManager.NetworkCallback = object : ConnectivityManager.NetworkCallback() {
override fun onAvailable(network: Network) {
Log.d(tag, "::onAvailable - Entry")
super.onAvailable(network)
}
override fun onUnavailable() {
Log.d(tag, "::onUnavailable - Entry")
super.onUnavailable()
}
}
This makes a connection in the app, but establishes the main connection via mobile data and I can't establish a connection because the server is unreachable. I have to find a way to make the connection through the network object in the onAvailable function.
Did you know how or is there an alternative way?
Solution
I found a method in the ConnectivityManager class the method is bindProcessToNetwork
connectivityManager.bindProcessToNetwork(network)

I found a method in the ConnectivityManager class the method is bindProcessToNetwork
connectivityManager.bindProcessToNetwork(network)