Develop Reference

Android app to dynamically turn on/off a wifi hotspot

I want to control wifi hotspot dynamically in my Android app project. I have tired Reflection (which will not work in Android Oreo and later versions), startLocalOnyNetwork (but I want specific SSID and PASSWORD, which is not possible to configure it).
Then I rooted my phone, Is it possible if the device is rooted ?
Expecting an api to turn on/off wifi hotspot with specific SSID and PASSWORD or use the previous one.
Any possibilities or workarounds ?
Thanks in advance.

To turn on Wifi Hotspot, need some permissions
<uses-permission android:name="android.permission.WRITE_SETTINGS"
tools:ignore="ProtectedPermissions" />
and the permission should be dynamically granted by user
In apps advanced settings -> Modify system settings
/**
* This enables tethering using the ssid/password defined in Settings App>Hotspot & tethering
* Does not require app to have system/privileged access
* Credit: Vishal Sharma - https://stackoverflow.com/a/52219887
*/
public boolean startTethering() {
File outputDir = mContext.getCodeCacheDir();
Object proxy;
try {
proxy = ProxyBuilder.forClass(OnStartTetheringCallbackClass())
.dexCache(outputDir).handler(new InvocationHandler() {
#Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
return null;
}
}).build();
} catch (Exception e) {
Log.e(TAG, "Error in enableTethering ProxyBuilder");
e.printStackTrace();
return false;
}
Method method = null;
try {
method = mConnectivityManager.getClass().getDeclaredMethod("startTethering", int.class, boolean.class, OnStartTetheringCallbackClass(), Handler.class);
if (method == null) {
Log.e(TAG, "startTetheringMethod is null");
} else {
method.invoke(mConnectivityManager, ConnectivityManager.TYPE_MOBILE, false, proxy, null);
Log.d(TAG, "startTethering invoked");
}
return true;
} catch (Exception e) {
Log.e(TAG, "Error in enableTethering");
e.printStackTrace();
}
return false;
}
public void stopTethering() {
try {
Method method = mConnectivityManager.getClass().getDeclaredMethod("stopTethering", int.class);
if (method == null) {
Log.e(TAG, "stopTetheringMethod is null");
} else {
method.invoke(mConnectivityManager, ConnectivityManager.TYPE_MOBILE);
Log.d(TAG, "stopTethering invoked");
}
} catch (Exception e) {
Log.e(TAG, "stopTethering error: " + e.toString());
e.printStackTrace();
}
}
Use above methods to turn on/off Wifi Hotspot with SSID and password defined in the settings.
private int AP_STATE_DISABLED = 11;
private int AP_STATE_ENABLING = 12;
private int AP_STATE_ENABLED = 13;
private int AP_STATE_ERROR = 14;
/**
* #return status hot spot enabled or not
*/
public boolean isHotSpotEnabled(Context context) {
Method method = null;
int actualState = 0;
try {
WifiManager mWifiManager = (WifiManager) context.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
method = mWifiManager.getClass().getDeclaredMethod("getWifiApState");
method.setAccessible(true);
actualState = (Integer) method.invoke(mWifiManager, (Object[]) null);
if (actualState == AP_STATE_ENABLING ||actualState == AP_STATE_ENABLED) {
return true;
}
} catch (IllegalArgumentException | NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
return false;
}
Above method can be used to get the current state of hotspot

Getting MAC address in Android 6.0

I'm developing an app that gets the MAC address of the device, but since Android 6.0 my code doesn't work, giving me an incorrect value.
Here's my code...
public String ObtenMAC()
{
WifiManager manager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
WifiInfo info = manager.getConnectionInfo();
return(info.getMacAddress().toUpperCase());
}
Instead of the real MAC address, it returns an strange code: 02:00:00:00:00:00.

Please refer to Android 6.0 Changes.
To provide users with greater data protection, starting in this release, Android removes programmatic access to the device’s local hardware identifier for apps using the Wi-Fi and Bluetooth APIs. The WifiInfo.getMacAddress() and the BluetoothAdapter.getAddress() methods now return a constant value of 02:00:00:00:00:00.
To access the hardware identifiers of nearby external devices via Bluetooth and Wi-Fi scans, your app must now have the ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION permissions.

Use below code to get Mac address in Android 6.0
public static String getMacAddr() {
try {
List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
for (NetworkInterface nif : all) {
if (!nif.getName().equalsIgnoreCase("wlan0")) continue;
byte[] macBytes = nif.getHardwareAddress();
if (macBytes == null) {
return "";
}
StringBuilder res1 = new StringBuilder();
for (byte b : macBytes) {
res1.append(Integer.toHexString(b & 0xFF) + ":");
}
if (res1.length() > 0) {
res1.deleteCharAt(res1.length() - 1);
}
return res1.toString();
}
} catch (Exception ex) {
//handle exception
}
return "";
}

I didn't get the above answer to work, but stumbled upon another answer.
Here is a complete and simple method on getting the IPv6 address and then getting the mac address from it.
How to get Wi-Fi Mac address in Android Marshmallow
public static String getMacAddr() {
try {
List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
for (NetworkInterface nif : all) {
if (!nif.getName().equalsIgnoreCase("wlan0")) continue;
byte[] macBytes = nif.getHardwareAddress();
if (macBytes == null) {
return "";
}
StringBuilder res1 = new StringBuilder();
for (byte b : macBytes) {
res1.append(String.format("%02X:",b));
}
if (res1.length() > 0) {
res1.deleteCharAt(res1.length() - 1);
}
return res1.toString();
}
} catch (Exception ex) {
}
return "02:00:00:00:00:00";
}
Tested it already and it works. Many thanks to Rob Anderson!

this is the complete 2 ways code of getting it successfully on Marshmallow , just copy past this and it will work !
//Android 6.0 : Access to mac address from WifiManager forbidden
private static final String marshmallowMacAddress = "02:00:00:00:00:00";
private static final String fileAddressMac = "/sys/class/net/wlan0/address";
public static String recupAdresseMAC(WifiManager wifiMan) {
WifiInfo wifiInf = wifiMan.getConnectionInfo();
if(wifiInf.getMacAddress().equals(marshmallowMacAddress)){
String ret = null;
try {
ret= getAdressMacByInterface();
if (ret != null){
return ret;
} else {
ret = getAddressMacByFile(wifiMan);
return ret;
}
} catch (IOException e) {
Log.e("MobileAccess", "Erreur lecture propriete Adresse MAC");
} catch (Exception e) {
Log.e("MobileAcces", "Erreur lecture propriete Adresse MAC ");
}
} else{
return wifiInf.getMacAddress();
}
return marshmallowMacAddress;
}
private static String getAdressMacByInterface(){
try {
List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
for (NetworkInterface nif : all) {
if (nif.getName().equalsIgnoreCase("wlan0")) {
byte[] macBytes = nif.getHardwareAddress();
if (macBytes == null) {
return "";
}
StringBuilder res1 = new StringBuilder();
for (byte b : macBytes) {
res1.append(String.format("%02X:",b));
}
if (res1.length() > 0) {
res1.deleteCharAt(res1.length() - 1);
}
return res1.toString();
}
}
} catch (Exception e) {
Log.e("MobileAcces", "Erreur lecture propriete Adresse MAC ");
}
return null;
}
private static String getAddressMacByFile(WifiManager wifiMan) throws Exception {
String ret;
int wifiState = wifiMan.getWifiState();
wifiMan.setWifiEnabled(true);
File fl = new File(fileAddressMac);
FileInputStream fin = new FileInputStream(fl);
StringBuilder builder = new StringBuilder();
int ch;
while((ch = fin.read()) != -1){
builder.append((char)ch);
}
ret = builder.toString();
fin.close();
boolean enabled = WifiManager.WIFI_STATE_ENABLED == wifiState;
wifiMan.setWifiEnabled(enabled);
return ret;
}
manifest :
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
Summary : this code will try to get the MAC address first by Interface and if its failed it get it by file system.
Note:for file System way, you need to enable WIFI to access the file.
thnx to Sam's answer here https://stackoverflow.com/a/39288868/3818437

You can get the MAC address from the IPv6 local address. E.g., the IPv6 address "fe80::1034:56ff:fe78:9abc" corresponds to the MAC address "12-34-56-78-9a-bc". See the code below. Getting the WiFi IPv6 address only requires android.permission.INTERNET.
See the Wikipedia page IPv6 address, particularly the note about "local addresses" fe80::/64 and the section about "Modified EUI-64".
/**
* Gets an EUI-48 MAC address from an IPv6 link-local address.
* E.g., the IPv6 address "fe80::1034:56ff:fe78:9abc"
* corresponds to the MAC address "12-34-56-78-9a-bc".
* <p/>
* See the note about "local addresses" fe80::/64 and the section about "Modified EUI-64" in
* the Wikipedia article "IPv6 address" at https://en.wikipedia.org/wiki/IPv6_address
*
* #param ipv6 An Inet6Address object.
* #return The EUI-48 MAC address as a byte array, null on error.
*/
private static byte[] getMacAddressFromIpv6(final Inet6Address ipv6)
{
byte[] eui48mac = null;
if (ipv6 != null) {
/*
* Make sure that this is an fe80::/64 link-local address.
*/
final byte[] ipv6Bytes = ipv6.getAddress();
if ((ipv6Bytes != null) &&
(ipv6Bytes.length == 16) &&
(ipv6Bytes[0] == (byte) 0xfe) &&
(ipv6Bytes[1] == (byte) 0x80) &&
(ipv6Bytes[11] == (byte) 0xff) &&
(ipv6Bytes[12] == (byte) 0xfe)) {
/*
* Allocate a byte array for storing the EUI-48 MAC address, then fill it
* from the appropriate bytes of the IPv6 address. Invert the 7th bit
* of the first byte and discard the "ff:fe" portion of the modified
* EUI-64 MAC address.
*/
eui48mac = new byte[6];
eui48mac[0] = (byte) (ipv6Bytes[8] ^ 0x2);
eui48mac[1] = ipv6Bytes[9];
eui48mac[2] = ipv6Bytes[10];
eui48mac[3] = ipv6Bytes[13];
eui48mac[4] = ipv6Bytes[14];
eui48mac[5] = ipv6Bytes[15];
}
}
return eui48mac;
}

I try to get mac address with 2 methods, first by Interface and if its failed, i get it by file system, but you need to enable wifi to access the file.
//Android 6.0 : Access to mac address from WifiManager forbidden
private static final String marshmallowMacAddress = "02:00:00:00:00:00";
private static final String fileAddressMac = "/sys/class/net/wlan0/address";
public static String recupAdresseMAC(WifiManager wifiMan) {
WifiInfo wifiInf = wifiMan.getConnectionInfo();
if(wifiInf.getMacAddress().equals(marshmallowMacAddress)){
String ret = null;
try {
ret= getAdressMacByInterface();
if (ret != null){
return ret;
} else {
ret = getAddressMacByFile(wifiMan);
return ret;
}
} catch (IOException e) {
Log.e("MobileAccess", "Erreur lecture propriete Adresse MAC");
} catch (Exception e) {
Log.e("MobileAcces", "Erreur lecture propriete Adresse MAC ");
}
} else{
return wifiInf.getMacAddress();
}
return marshmallowMacAddress;
}
private static String getAdressMacByInterface(){
try {
List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
for (NetworkInterface nif : all) {
if (nif.getName().equalsIgnoreCase("wlan0")) {
byte[] macBytes = nif.getHardwareAddress();
if (macBytes == null) {
return "";
}
StringBuilder res1 = new StringBuilder();
for (byte b : macBytes) {
res1.append(String.format("%02X:",b));
}
if (res1.length() > 0) {
res1.deleteCharAt(res1.length() - 1);
}
return res1.toString();
}
}
} catch (Exception e) {
Log.e("MobileAcces", "Erreur lecture propriete Adresse MAC ");
}
return null;
}
private static String getAddressMacByFile(WifiManager wifiMan) throws Exception {
String ret;
int wifiState = wifiMan.getWifiState();
wifiMan.setWifiEnabled(true);
File fl = new File(fileAddressMac);
FileInputStream fin = new FileInputStream(fl);
ret = convertStreamToString(fin);
fin.close();
boolean enabled = WifiManager.WIFI_STATE_ENABLED == wifiState;
wifiMan.setWifiEnabled(enabled);
return ret;
}
Add this line to your manifest.
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
I recommend you to persist your mac address in your preferences like here
mac = activity.getSharedPreferences("MAC_ADDRESS", Context.MODE_PRIVATE).getString("MAC_ADDRESS", "");
if(mac == null || mac.equals("")){
WifiManager wifiMan = (WifiManager) activity.getSystemService(Context.WIFI_SERVICE);
mac = MobileAccess.recupAdresseMAC(wifiMan);
if(mac != null && !mac.equals("")){
SharedPreferences.Editor editor = activity.getSharedPreferences("MAC_ADDRESS", Context.MODE_PRIVATE).edit();
editor.putString("MAC_ADDRESS", mac).commit();
}
}

Its Perfectly Fine
package com.keshav.fetchmacaddress;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Collections;
import java.util.List;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.e("keshav","getMacAddr -> " +getMacAddr());
}
public static String getMacAddr() {
try {
List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
for (NetworkInterface nif : all) {
if (!nif.getName().equalsIgnoreCase("wlan0")) continue;
byte[] macBytes = nif.getHardwareAddress();
if (macBytes == null) {
return "";
}
StringBuilder res1 = new StringBuilder();
for (byte b : macBytes) {
res1.append(Integer.toHexString(b & 0xFF) + ":");
}
if (res1.length() > 0) {
res1.deleteCharAt(res1.length() - 1);
}
return res1.toString();
}
} catch (Exception ex) {
//handle exception
}
return "";
}
}

First you need to add Internet user permission.
<uses-permission android:name="android.permission.INTERNET" />
Then you can find the mac over the NetworkInterfaces API.
public static String getMacAddr() {
try {
List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
for (NetworkInterface nif : all) {
if (!nif.getName().equalsIgnoreCase("wlan0")) continue;
byte[] macBytes = nif.getHardwareAddress();
if (macBytes == null) {
return "";
}
StringBuilder res1 = new StringBuilder();
for (byte b : macBytes) {
res1.append(String.format("%02X:",b));
}
if (res1.length() > 0) {
res1.deleteCharAt(res1.length() - 1);
}
return res1.toString();
}
} catch (Exception ex) {
}
return "02:00:00:00:00:00";
}

The answers are mostly correct, but keep care, that there is a change in android 7. You will need to use the
DevicePolicyManager and the Method getWifiMacAddress. The official docs has a typo, which means that you shouldnt copy/paste it from there.
DevicePolicyManager.getWifiMacAddress()
Refs:
https://developer.android.com/about/versions/nougat/android-7.0-changes.html
Get Device mac adress in Android Nougat and O programmatically

Use wifiInfo.getBSSID() to get Mac Address of AccessPoint instead of getMacAddress method.

This is a more kotlin way to get Mac Address
fun getMacAddress(): String =
NetworkInterface.getNetworkInterfaces().toList()
.firstOrNull { it.name.equals("wlan0", ignoreCase = true) }?.let {
it.hardwareAddress?.let { macBytes ->
StringBuilder().apply {
for (b in macBytes) {
append(String.format("%02X:", b))
}
if (isNotEmpty()) {
deleteCharAt(lastIndex)
}
}
}.toString()
} ?: "02:00:00:00:00:00"

Android - jmdns doesn't discover devices

I'm trying to implement a class to discover services on the network.
I've tried working with Android's NSD and it does discover the services fine, but it supports only API levels 16 and up, and I can't seem to retrieve the txtRecord field within the service info (it returns null for some reason). Turns out it's a known problem...
So now I'm trying to work with jmDNS, which doesn't seem to find services at all.
here's my class (I'm working with the AndroidAnnotations framework) MDnsHelper:
#EBean
public class MDnsHelper implements ServiceListener {
public static final String SERVICE_TYPE = "_http._tcp.local";
Activity activity;
private JmDNS jmdns;
private MulticastLock multicastLock;
WifiManager wm;
InetAddress bindingAddress;
boolean isDiscovering;
public void init(Activity activity) {
this.activity = activity;
isDiscovering = false;
wm = (WifiManager) activity.getSystemService(Context.WIFI_SERVICE);
multicastLock = wm.createMulticastLock(activity.getPackageName());
multicastLock.setReferenceCounted(false);
}
#Background
public void startDiscovery() {
if (isDiscovering)
return;
System.out.println("starting...");
multicastLock.acquire();
try {
System.out.println("creating jmdns");
jmdns = JmDNS.create();
System.out.println("jmdns created");
} catch (IOException e) {
e.printStackTrace();
} finally {
if (jmdns != null) {
jmdns.addServiceListener(SERVICE_TYPE, MDnsHelper.this);
isDiscovering = true;
System.out.println("discovering services of type: " + SERVICE_TYPE);
}
}
}
#Background
public void stopDiscovery() {
if (!isDiscovering || jmdns == null)
return;
System.out.println("stopping...");
multicastLock.release();
jmdns.removeServiceListener(SERVICE_TYPE, MDnsHelper.this);
System.out.println("listener for " + SERVICE_TYPE + " removed");
try {
jmdns.close();
isDiscovering = false;
System.out.println("jmdns closed");
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
public void serviceAdded(ServiceEvent service) {
System.out.println("found: " + service.getInfo().toString());
}
#Override
public void serviceRemoved(ServiceEvent service) {
System.out.println("lost: " + service.getInfo().toString());
}
#Override
public void serviceResolved(ServiceEvent service) {
System.out.println("resolved: " + service.getInfo().toString());
}
}
And in my app I call:
init(getActivity());
And then startDiscovery(); to start scanning and stopDiscovery(); to stop scanning.
And of course, I gave the app the required permissions in the manifest...
What am I missing here?
If you need me to provide additional code/info - just ask.
thanks!!

I am the author of ZeroConf Browser for Android and I use the open source Library JmDNS for all my resolving. It works great but there are a few tricks to getting it to work properly.
In your Android manifest.xml make sure you have these permissions at least.
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
Before starting the activity you must allow multi-cast packets by acquiring a multicast lock.
#Override
protected void onStart() {
Log.i(TAG, "Starting ServiceActivity...");
super.onStart();
try {
Log.i(TAG, "Starting Mutlicast Lock...");
WifiManager wifi = (WifiManager) this.getSystemService(Context.WIFI_SERVICE);
// get the device ip address
final InetAddress deviceIpAddress = getDeviceIpAddress(wifi);
multicastLock = wifi.createMulticastLock(getClass().getName());
multicastLock.setReferenceCounted(true);
multicastLock.acquire();
Log.i(TAG, "Starting ZeroConf probe....");
jmdns = JmDNS.create(deviceIpAddress, HOSTNAME);
jmdns.addServiceTypeListener(this);
} catch (IOException ex) {
Log.e(TAG, ex.getMessage(), ex);
}
Log.i(TAG, "Started ZeroConf probe....");
}
private InetAddress getDeviceIpAddress(WifiManager wifi) {
InetAddress result = null;
try {
// default to Android localhost
result = InetAddress.getByName("10.0.0.2");
// figure out our wifi address, otherwise bail
WifiInfo wifiinfo = wifi.getConnectionInfo();
int intaddr = wifiinfo.getIpAddress();
byte[] byteaddr = new byte[] { (byte) (intaddr & 0xff), (byte) (intaddr >> 8 & 0xff),
(byte) (intaddr >> 16 & 0xff), (byte) (intaddr >> 24 & 0xff) };
result = InetAddress.getByAddress(byteaddr);
} catch (UnknownHostException ex) {
Log.w(TAG, String.format("getDeviceIpAddress Error: %s", ex.getMessage()));
}
return result;
}
And don't forget on stopping the scan to unlock the multicast lock and shut down JmDNS.
#Override
protected void onStop() {
Log.i(TAG, "Stopping ServiceActivity...");
super.onStop();
stopScan();
}
private static void stopScan() {
try {
if (jmdns != null) {
Log.i(TAG, "Stopping ZeroConf probe....");
jmdns.unregisterAllServices();
jmdns.close();
jmdns = null;
}
if (multicastLock != null) {
Log.i(TAG, "Releasing Mutlicast Lock...");
multicastLock.release();
multicastLock = null;
}
} catch (Exception ex) {
Log.e(TAG, ex.getMessage(), ex);
}
}
Most importanty don't use the default constructor. You must use the IP Address Constructor. I noticed in your code you are just doing JmDNS.create(). I think for some reason the only way it works on Android is to use the contructor below.
jmdns = JmDNS.create(deviceIpAddress, HOSTNAME);

If you are having this error in Android Oreo 8.x, this might help you.
First, Remember to make sure you have added these permissions into your Android manifest.xml.
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
Acquire a multicast lock to allow multi-cast packets.
WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
MulticastLock lock = wifi.createMulticastLock("jmdns-multicast-lock");
lock.setReferenceCounted(true);
lock.acquire();
Now, use only this constructor JmDNS.create(InetAddress addr, String name) to create an instance of JmDNS and bind it to a specific network interface given its IP-address, like this:
try {
jmDNS = JmDNS.create(InetAddress.getByName(obtainIPv4Address(info)), HOST_NAME);
} catch (IOException e) {
LogHelper.e(TAG, "Error in JmDNS creation: " + e);
}
Finally, just make sure to call JmDNSunreisterAllServices(), and JmDNS.close() to stop JmDNS stream and releases any system resources associated with it. Also, call MulticastLock.release() to unlock the multicast lock when you're done with it.
try {
if (jmDNS != null) {
jmDNS.unregisterAllServices();
jmDNS.close();
jmDNS = null;
}
if (lock != null) {
lock.release();
lock = null;
}
} catch (Exception e) {
e.printStackTrace();
}

Bind Socket Android

I have a problem on android. I have an application that asks the user for the local Ip address (from the device's interface) and another remote address. The application has to bind to the specified local address and connect to the remote address. Quite simple, but, indeed, bind does not work ass i expected..
I added the following permissions on the manifest file:
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
The source code is the following one:
public class MainActivity extends Activity
{
String Tag = "TAG";
private int LOCAL_PORT = 4444;
private int REMOTE_PORT = 80;
private EditText LOCAL;
private EditText REMOTE;
private Button Connect;
private TextView STATUS;
private Context context = this;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
LOCAL = (EditText) findViewById(R.id.editText1);
REMOTE = (EditText) findViewById(R.id.editText2);
Connect = (Button) findViewById(R.id.button1);
Connect.setOnClickListener(new View.OnClickListener() {
public void onClick(View v)
{
BotleneckHandle WORK;
Toast.makeText(getApplicationContext(), "Proceeding to connect",
Toast.LENGTH_SHORT).show();
/*
if(LOCAL.getText().toString() == null || REMOTE.getText().toString() == null || LOCAL.getText().toString().equals(" ") || REMOTE.getText().toString().equals(" ") || LOCAL.getText().toString().equals("") || REMOTE.getText().toString().equals(""))
Toast.makeText(context, "Wrong parameters", 2000);
else
{
Toast.makeText(getApplicationContext(), "Proceeding to connect",Toast.LENGTH_SHORT).show();
}*/
WORK = new BotleneckHandle();
WORK.execute();
}
});
STATUS = (TextView) findViewById(R.id.textView1);
}
private class BotleneckHandle extends AsyncTask <Void , Void , String>
{
Socket Skt = null;
String ReturnStatemente = new String();
SocketAddress localAddr = new InetSocketAddress(LOCAL.getText().toString(), LOCAL_PORT);
protected void onPreExecute(){ }
protected String doInBackground(Void... params)
{
try
{
String s=new String();
s+= "Local="+LOCAL.getText().toString()+":"+LOCAL_PORT+" Remote="+REMOTE.getText().toString()+":"+REMOTE_PORT; //so far so good, Confirmed by debug
Toast.makeText(getApplicationContext(), s,Toast.LENGTH_SHORT).show(); //Does not show anything due the fact that i didn't published it as an assync task update..
//binding to a local address
Skt.bind(localAddr); //cannot make the bind :-/
//connecting to remote host
Skt=new Socket(REMOTE.getText().toString(), REMOTE_PORT); //if bind is comment, still does not work.. I bet
ReturnStatemente = "Connected";
}
catch (UnknownHostException e)
{
e.printStackTrace();
Toast.makeText(context, "Unknown remote host", 2000);
ReturnStatemente = "Not Connected";
}
catch (IOException e)
{
e.printStackTrace();
Toast.makeText(context, "Connection fail", 2000);
ReturnStatemente = "Not Connected";
}
finally{try {
Skt.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}}
return ReturnStatemente;
}
protected void onPostExecute(String result) { STATUS.setText(" CONECTION STATUS == " + result); }
}
}
What am i doing wrong on bind? As far as i see, and as i searched for its good.. Did i miss something?
kind regards

You're trying to call bind on a variable before you assigned anything to it. So its still null. That isn't going to work. You need to create an instance of Socket before you can call methods on it.

How to create access point programmatically

I've written the code to create an access point for android devices. I've tested on both emulator and real device.But it doesn't work. Where did i get wrong?
public class MainWAP extends Activity {
WifiManager wifiManager;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_wap);
}
public void openWifi(View v) {
createWifiAccessPoint();
}
private void createWifiAccessPoint() {
if (wifiManager.isWifiEnabled()) {
wifiManager.setWifiEnabled(false);
}
Method[] wmMethods = wifiManager.getClass().getDeclaredMethods();
boolean methodFound = false;
for (Method method: wmMethods) {
if (method.getName().equals("setWifiApEnabled")) {
methodFound = true;
WifiConfiguration netConfig = new WifiConfiguration();
netConfig.SSID = "AccessPoint";
netConfig.allowedAuthAlgorithms.set(
WifiConfiguration.AuthAlgorithm.OPEN);
try {
boolean apstatus = (Boolean) method.invoke(
wifiManager, netConfig, true);
for (Method isWifiApEnabledmethod: wmMethods) {
if (isWifiApEnabledmethod.getName().equals(
"isWifiApEnabled")) {
while (!(Boolean) isWifiApEnabledmethod.invoke(
wifiManager)) {};
for (Method method1: wmMethods) {
if (method1.getName().equals(
"getWifiApState")) {
int apstate;
apstate = (Integer) method1.invoke(
wifiManager);
}
}
}
}
if (apstatus) {
Log.d("Splash Activity",
"Access Point created");
} else {
Log.d("Splash Activity",
"Access Point creation failed");
}
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
}
}
if (!methodFound) {
Log.d("Splash Activity",
"cannot configure an access point");
}
}
}

Your WiFiManager is definately not initialized.
In your onCreate method add this:
wifiManager = (WiFiManager) getSystemService(Context.WIFI_SERVICE);

You need few things to make this code to work.
1) Init wifiManager onCreate() :
WifiManager wifiManager = (WiFiManager) getSystemService(Context.WIFI_SERVICE);
2) You need to ask for this permissions in you AndroidManifest.xml :
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.WRITE_APN_SETTINGS" />
3) Your application need to be signed with system certificates.

With your method of exploiting undocumented APIs using reflection, things might not work well in all scenarios.
Well, you can try adding these in your manifest file and give a try.
android.permission.ACCESS_WIFI_STATE
android.permission.CHANGE_WIFI_STATE
android.permission.WRITE_APN_SETTINGS