Is Android WifiP2pManager.discoverServices able to discover NsdServiceInfo (by NsdManager.registerService)?

2017-12-16 13:57 Amos imported from Stackoverflow

step 1:

nsdManager.registerService(serviceInfo, NsdManager.PROTOCOL_DNS_SD, registrationListener);

step 2:

p2pManager.discoverServices(p2pChannel, new WifiP2pManager.ActionListener() {
    @Override
    public void onSuccess() {
        ...
    }

    @Override
    public void onFailure(int code) {
        ...
    }
});

So, is step 2 able to discover step 1's service?

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I was following the instructions as said in the GitHub webpage and when i type in the cmd "pip install beeware" it starts working and at some point it says

"Command "c:\users\jose\beeware\venv\scripts\python.exe -u -c "import setuptools, tokenize;file='C:\Users\Public\Documents\Wondershare\CreatorTemp\pip-install-qv6b5gmo\pythonnet\setup.py';f=getattr(tokenize, 'open', open)(file);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, file, 'exec'))" install --record C:\Users\Public\Documents\Wondershare\CreatorTemp\pip-record-j0v07yaq\install-record.txt --single-version-externally-managed --compile --install-headers c:\users\jose\beeware\venv\include\site\python3.7\pythonnet" failed with error code 1 in C:\Users\Public\Documents\Wondershare\CreatorTemp\pip-install-qv6b5gmo\pythonnet\" which i do not know how to solve or what to do. Thanks everybody.

Whats wrong with this simple var assignment in Kotlin?

I've this RecyclerView adapter class which has a method offsetRound in it.

class LeagueRoundAdapter(private val rounds: List<RoundVO>) : RecyclerView.Adapter<MatchViewHolder>() {
    private var round: Int = 0
        set(value) {
            matches = rounds[value].matches

            notifyDataSetChanged()
        }


    fun offsetRound(offset: Int): Int {
        var newround = round + offset;
        if (newround !in 0 until rounds.size) {
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        round = newround
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    }

    private var matches = rounds[round].matches


    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MatchViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.item_match, parent, false)
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    }

    override fun getItemCount(): Int {
        return rounds[round].matches.size
    }


    override fun onBindViewHolder(holder: MatchViewHolder, position: Int) {
        val matchVO = matches[position]
        holder.bind(matchVO)
    }
}

When I push A prev/next button I want to increment/decrement the current round:

private fun setupEvents(){
    btn_next_round.setOnClickListener{
        val round = getAdapter().offsetRound(Integer.parseInt(btn_next_round.tag as String))
        txt_round_info.text = "$round"
    }

    btn_prev_round.setOnClickListener{
        val round = getAdapter().offsetRound(Integer.parseInt(btn_prev_round.tag as String))
        txt_round_info.text = "$round"
    }
}

the button tags are "1" and "-1".

The problem is that in this line round = newround the variable round doesn't take the value of newround, as you can see in this debug print:

Before assignment:

After:

I'm kind of sleepy at the moment. Am I doing something stupid that I can not figure out?

Passing C# byte Array to Native C/C++ Shared Library Android Plug-in

I am working on passing an image stored as an array of RGBA colors in 32 bit format from C# to a native plug-in for Android written in C/C++ and packaged in a shared library. My attempt was to unravel the colors into an extended byte array and pass that to a native function with a JNI jbooleanArray parameter, since JNI typedef's unsigned char as jboolean. However, the data isn't crossing the unmanaged boundary properly: I get a SEGFAULT when I call GetBooleanArrayElements. Also, the int image height passed as a jint parameter in the same function becomes negative, which it wasn't originally. My guess is there's some memory alignment/padding issues throwing everything out of whack.

This is the C library function:

JNIEXPORT void JNICALL Detect(JNIEnv* env, jobject jobj, jbooleanArray rawImagePixelsUnraveled, jint imageWidth, jint imageHeight, jint maxDetectedShapes, jintArray outDetectedShapesCountSingleArray, jintArray outPointsPerShapeArray)
{
  //assert(imageHeight >= 0);
  jboolean isRawImagePixelsUnraveledCopy;
  jboolean* rawImagePixelsUnraveledArray = env->GetBooleanArrayElements(rawImagePixelsUnraveled, &isRawImagePixelsUnraveledCopy);
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This is the relevant calling C# code:

byte[] rawImagePixelsUnraveled = OpenCVInterop.Color32ArrayUnraveled(rawImagePixels);
IntPtr unmanagedArray = Marshal.AllocHGlobal(rawImagePixelsUnraveled.Length);
Marshal.Copy(rawImagePixelsUnraveled, 0, unmanagedArray, rawImagePixelsUnraveled.Length);
OpenCVInterop.Detect(unmanagedArray, phoneCameraDisplay.RenderingCameraTexture.width, phoneCameraDisplay.RenderingCameraTexture.height, _maxShapeDetectCount, ref _detectedShapesCount, _pointsPerShape);
Marshal.FreeHGlobal(unmanagedArray);

internal static class OpenCVInterop
{
    static internal byte[] Color32ArrayUnraveled(Color32[] color32Array)
    {
        byte[] unraveledColor32Array = new byte[color32Array.Length * 4];
        for(int i = 0; i < color32Array.Length; ++i)
        {
            unraveledColor32Array[4 * i] = color32Array[i].r;
            unraveledColor32Array[4 * i + 1] = color32Array[i].g;
            unraveledColor32Array[4 * i + 2] = color32Array[i].b;
            unraveledColor32Array[4 * i + 3] = color32Array[i].a;
        }
        return unraveledColor32Array;
    }

    [DllImport("native-lib")]
    internal static extern void Detect(IntPtr/*byte[]*/ rawImagePixels, int imageWidth, int imageHeight, int maxOutShapesCount, ref int outDetectedShapesCount, int[] outPointsPerShape);
}

I tried both sending the byte array itself and copying it to an IntPtr without success. How can I send the byte array from C# over to C-land properly? Thanks.

RecyclerView not being updated with [WIFI DIRECT] discovery

I have a database(SQLite) with specific "device names" and will be added to a RecyclerView while changing the TextView to Online/Offline depending on the device status.

Devices status are determined when I do an onClickListener of a button running this:

refreshBtn.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        mManager.discoverPeers(mChannel, new WifiP2pManager.ActionListener() {
            @Override
            public void onSuccess() {
                Toast.makeText(getApplicationContext(),"Scanning for devices",Toast.LENGTH_LONG).show();
            }

            @Override
            public void onFailure(int reason) {
                Toast.makeText(getApplicationContext(),"Scanning failed",Toast.LENGTH_LONG).show();
            }
        });
    }
});

PeerListListener:

  WifiP2pManager.PeerListListener peerListListener = new WifiP2pManager.PeerListListener() {
        @Override
        public void onPeersAvailable(WifiP2pDeviceList peerList) {
            loadingBar.setVisibility(View.VISIBLE);
            if(!peerList.getDeviceList().equals(peers)){
                peers.clear();
                peers.addAll(peerList.getDeviceList());

                deviceNameArray = new String[peerList.getDeviceList().size()];
                deviceArray     = new WifiP2pDevice[peerList.getDeviceList().size()];
                int index       = 0;
                int dbindex;

                //loadingBar.setMax(deviceDetails.size());
                //loadingBar.setProgress(0);

                for(WifiP2pDevice device : peerList.getDeviceList()){
                    deviceNameArray[index] = device.deviceName;


                    System.out.printf(deviceNameArray[index]);


                    deviceArray[index]     = device;
                    for(dbindex = 0;dbindex<deviceDetails.size();dbindex++) {
                        if(!deviceDetails.get(dbindex).getStatus().equals("lock") || !deviceDetails.get(dbindex).getStatus().equals("maintenance")) {
                            if (deviceDetails.get(dbindex).getDeviceNo().equals(deviceNameArray[index])) {
                                deviceDetails.get(dbindex).setStatus("online");
                            } else {
                                deviceDetails.get(dbindex).setStatus("offline");
                            }
                        }
                    }
                    index++;
                    //loadingBar.setProgress(index);
                }
                mAdapter = new DeviceAdapter(UserMain.this,deviceDetails);
                mAdapter.notifyDataSetChanged();
                mRecyclerView.setAdapter(mAdapter);

//                ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(),android.R.layout.simple_list_item_1,deviceNameArray);
//                listView.setAdapter(adapter);
            }
            if(peers.size() == 0){
                Toast.makeText(getApplicationContext(),"No Device Found..",Toast.LENGTH_SHORT).show();
                return;
            }
            loadingBar.setVisibility(View.INVISIBLE);
        }
    };

I tried printing the deviceNameArray and the devices do show up on the console name but the RecycleView isn't updated at all.

Part of my RecyclerView Custom Adapter:

@NonNull
@Override
public DeviceAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View v = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.user_main_card,parent,false);

    ViewHolder vh = new ViewHolder(v);
    return vh;
}

@Override
public void onBindViewHolder(@NonNull DeviceAdapter.ViewHolder holder, final int position) {
    holder.deviceNo.setText("No." +deviceDetails.get(position).getDeviceNo());

    if(deviceDetails.get(position).getStatus().equals("online")) {
        holder.deviceStatus.setText("ONLINE");
    }else if(deviceDetails.get(position).getStatus().equals("offline") || deviceDetails.get(position).getStatus().equals("maintenance")){
        if(deviceDetails.get(position).getStatus().equals("offline")){
            holder.deviceStatus.setText("OFFLINE");

        }else if(deviceDetails.get(position).getStatus().equals("maintenance")){
            holder.deviceStatus.setText("MAINTENANCE");

        }
    }



    holder.cardView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if(deviceDetails.get(position).getStatus().equals("offline") || deviceDetails.get(position).getStatus().equals("maintenance")) {
                Toast.makeText(mContext, deviceDetails.get(position).getDeviceName(), Toast.LENGTH_SHORT).show();
            }
            if(deviceDetails.get(position).getStatus().equals("online")){
                ((UserMain)mContext).connect(deviceDetails.get(position).getDeviceNo());
            }
        }
    });
}

I tried using:

mAdapter.notifyDataSetChanged();

But it doesn't seem to help.

android: Share internet on the p2p group

I have an android phone with a wifi connection that creates a Wifi P2P group. So it will be the host of the group. I have another android phone which is a client of the group. It has the network name and the passworld using discovery services. So he can connect to the access point created by the host phone. Now, How can I share internet connection from the host phone to the client phone? I know that some apps are able to do it such as netshare. I think they are using a VPN routing but how does they do that (programmatically of course)? Do you have an idea?
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I have a NodeMCU module with web server. I also use mDNS to register a local service, so the server can be accessed by url on local network. NodeMCU module and all mobile devices are obviously connected to same wifi network.

On iOS it works in all cases just by using local url (like http://myurl.local). On Android, I have to resolve IP address first (using NsdManager). I am not providing Android code as it's absolutely basic example for discovering local services and resolving their IPs. It is working in all cases except one:

1) Cheap chinese version of TP-LINK router, probably 2-3 years old. Works.

2) Hotspot opened by iOS device. Works.

3) Old D-link DIR-615 router, the hardware is probably 8 years old, firmware - 6 years old. Neither NsdManager discovering nor resolving are not working.

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I start the discovery with NsdManager with:
```
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```
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The failing scenario

Two devices running the app. I hit register on the first device and after I see a toast that confirms the registration I hit discover on the other.

The service is discovered by the second device but it's type its unknown. From debuging I saw that the unknown service type is

_mynsd._tcp.

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public class MainActivity extends AppCompatActivity {
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    private NsdManager.RegistrationListener registrationListener;
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    }

    public void onConnectClicked(View view) {

    }

    @Override
    protected void onPause() {
        super.onPause();
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    public void registerService(int port) {
        NsdServiceInfo serviceInfo = new NsdServiceInfo();
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    public void initializeServerSocket() {
        try {
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            Toast.makeText(this, "Error with server socket", Toast.LENGTH_SHORT).show();
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        discoveryListener = new NsdManager.DiscoveryListener() {
            @Override
            public void onStartDiscoveryFailed(String s, int i) {
                Toast.makeText(MainActivity.this, "Start discovery failed", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onStopDiscoveryFailed(String s, int i) {
                Toast.makeText(MainActivity.this, "Stop discovery failed ", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onDiscoveryStarted(String s) {
                Toast.makeText(MainActivity.this, "Started discovery", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onDiscoveryStopped(String s) {
                Toast.makeText(MainActivity.this, "Stopped discovery", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onServiceFound(NsdServiceInfo nsdServiceInfo) {
                Toast.makeText(MainActivity.this, nsdServiceInfo.getServiceName() + " service found", Toast.LENGTH_SHORT).show();

                if (!nsdServiceInfo.getServiceType().equals(SERVICE_TYPE)) {
                    Toast.makeText(MainActivity.this, "Unknown service type "+nsdServiceInfo.getServiceType(), Toast.LENGTH_SHORT).show();
                } else if (nsdServiceInfo.getServiceName().equals(serviceName)) {
                    // The one who registered the service is the one which actually holds the
                    // service name and its not null, so if we are here its the same machine
                    // who registered the service in the first place.
                    Toast.makeText(MainActivity.this, "Same machine: " + serviceName, Toast.LENGTH_SHORT).show();
                } else if (nsdServiceInfo.getServiceName().contains("MyNsd")) {
                    nsdManager.resolveService(nsdServiceInfo, new NsdManager.ResolveListener() {
                        @Override
                        public void onResolveFailed(NsdServiceInfo nsdServiceInfo, int i) {
                            Toast.makeText(MainActivity.this, "Could not resolve " + nsdServiceInfo.getServiceName(), Toast.LENGTH_SHORT).show();
                        }

                        @Override
                        public void onServiceResolved(NsdServiceInfo nsdServiceInfo) {
                            Toast.makeText(MainActivity.this, "Resolved  " + nsdServiceInfo.getServiceName(), Toast.LENGTH_SHORT).show();
                            if (nsdServiceInfo.getServiceName().equals(serviceName)){
                                Toast.makeText(MainActivity.this, "Same IP", Toast.LENGTH_SHORT).show();
                                return;
                            }

                            service = nsdServiceInfo;
                            int port = service.getPort();
                            InetAddress host = service.getHost();
                        }
                    });
                }
            }

            @Override
            public void onServiceLost(NsdServiceInfo nsdServiceInfo) {
                Toast.makeText(MainActivity.this, nsdServiceInfo.getServiceName() + " service lost", Toast.LENGTH_SHORT).show();
            }
        };
    }

    public void initializeRegistrationListener() {
        registrationListener = new NsdManager.RegistrationListener() {
            @Override
            public void onRegistrationFailed(NsdServiceInfo nsdServiceInfo, int i) {
                Toast.makeText(MainActivity.this, "Registration failed!", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onUnregistrationFailed(NsdServiceInfo nsdServiceInfo, int i) {
                Toast.makeText(MainActivity.this, "Unregistration failed", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onServiceRegistered(NsdServiceInfo nsdServiceInfo) {
                Toast.makeText(MainActivity.this, "Service registered", Toast.LENGTH_SHORT).show();
                serviceName = nsdServiceInfo.getServiceName();
            }

            @Override
            public void onServiceUnregistered(NsdServiceInfo nsdServiceInfo) {
                Toast.makeText(MainActivity.this, "Service unregistered", Toast.LENGTH_SHORT).show();
            }
        };
    }
}

and here is the layout:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/register"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginTop="8dp"
        android:onClick="onRegisterClicked"
        android:text="Register"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/discover"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginTop="8dp"
        android:onClick="onDiscoverClicked"
        android:text="Discover"
        app:layout_constraintStart_toEndOf="@+id/register"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/connect"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginTop="8dp"
        android:onClick="onConnectClicked"
        android:text="connect"
        app:layout_constraintStart_toEndOf="@+id/discover"
        app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

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Is Android WifiP2pManager.discoverServices able to discover NsdServiceInfo (by NsdManager.registerService)?

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