Create server TCP in Winodws Univeral App (Javascript) and client Android - windows

I want create a tcp server in c# and use it in universal app javascript based project, and I create the folowing code (Server):
//C# Windows Runtime Component
public sealed class Server
{
public Server()
{
Debug.WriteLine("Server...");
}
public async void Connection()
{
IPAddress ip = IPAddress.Parse("192.168.0.10");
TcpListener server = new TcpListener(ip, portNumber);
TcpClient client = default(TcpClient);
try
{
server.Start();
Debug.WriteLine("Server started ... " + ip.ToString());
}
catch (Exception e)
{
Debug.WriteLine(e.ToString());
}
while (true)
{
client = await server.AcceptTcpClientAsync();
byte[] recievedBuffer = new byte[100];
NetworkStream stream = client.GetStream();
stream.Read(recievedBuffer, 0, recievedBuffer.Length);
string msg = Encoding.UTF8.GetString(recievedBuffer, 0, recievedBuffer.Length);
Debug.WriteLine(msg);
}
}
}
//in HTML
<script>
console.log("test");
var server = new Server.Server();
server.connection();
console.log("msg");
</script>
I don't know why Debug.WriteLine and console.log method don't work, nothing are printed in output or in javascript console.
The Server code works with Android client, if the server is "Console App" project but in "Universal App Javscript" nothing append, I don't have warning or error.
So I don't know if I'm doing bad, because console.log and Debug.WriteLine don't work.

I have a solution that work with windows universal app, I remove Connection and add followings methods:
public async void StartServer()
{
try
{
var streamSocketListener = new Windows.Networking.Sockets.StreamSocketListener();
streamSocketListener.ConnectionReceived += this.StreamSocketListener_ConnectionReceived;
await streamSocketListener.BindEndpointAsync(new HostName("192.168.0.10"), PortNumber);
}
catch (Exception ex){}
}
private async void StreamSocketListener_ConnectionReceived(Windows.Networking.Sockets.StreamSocketListener sender, Windows.Networking.Sockets.StreamSocketListenerConnectionReceivedEventArgs args)
{
string request;
using (var streamReader = new StreamReader(args.Socket.InputStream.AsStreamForRead()))
{
request = await streamReader.ReadLineAsync();
}
sender.Dispose();
}
//in main.js just call this method
new Server.Server().startServer();
But I still don't know why Debug.WriteLine() in c# and console.log() in javascript don't work.

Related

Xamarin.Forms Calling Dialog from Xamarin.Android Project Throws an Exception

I've been trying to call a Dialog Alert from my xamarin.forms app using IoC container so far I haven't been able to display an alert in my app using this code:
Code at my viewModel:
await _dialogService.DisplayMessageAsync("ERROR", "There are errors on your form!", "Cancel", null);
at my shared project I have this DialogService which is the one I call from my viewModel:
public class DialogService : IDialogService
{
readonly IDialogService _dialogService;
public DialogService()
{
_dialogService = DependencyService.Get<IDialogService>();
}
public void CloseAllDialogs()
{
_dialogService.CloseAllDialogs();
}
public async Task DisplayMessageAsync(string title, string message, string buttonCancelName, Action callback)
{
await _dialogService.DisplayMessageAsync(title, message, buttonCancelName, callback);
}
public async Task DisplayMessageConfirmAsync(string title, string message, string buttonOkName, string buttonCancelName, Action<bool> callback)
{
await _dialogService.DisplayMessageConfirmAsync(title, message, buttonOkName, buttonCancelName, callback);
}
}
so at my Xamarin.Android.XXXXX I have the implementation of my DialogService which is call from my DialogService at my Shared Project this is the code:
public class DialogService : IDialogService
{
List<AlertDialog> _openDialogs = new List<AlertDialog>();
public void CloseAllDialogs()
{
foreach (var dialog in _openDialogs)
{
dialog.Dismiss();
}
_openDialogs.Clear();
}
public async Task DisplayMessageAsync(string title, string message, string okButton, Action callback)
{
await Task.Run(() => Alert(title, message, okButton, callback));
}
public async Task DisplayMessageConfirmAsync(string title, string message, string okButton, string cancelButton, Action<bool> callback)
{
await Task.Run(() => AlertConfirm(title, message, okButton, cancelButton, callback));
}
bool Alert(string title, string content, string okButton, Action callback)
{
var activity = (Activity)Forms.Context;
//var activity = (Activity)Android.App.Application.Context;
var alert = new AlertDialog.Builder(Android.App.Application.Context);
//var alert = new AlertDialog.Builder(activity);
alert.SetTitle(title);
alert.SetMessage(content);
alert.SetNegativeButton(okButton, (sender, e) =>
{
if (!Equals(callback, null))
{
callback();
}
_openDialogs.Remove((AlertDialog)sender);
});
Device.BeginInvokeOnMainThread(() =>
{
AlertDialog dialog = alert.Show();
_openDialogs.Add(dialog);
dialog.SetCanceledOnTouchOutside(false);
dialog.SetCancelable(false);
});
return true;
}
bool AlertConfirm(string title, string content, string okButton, string cancelButton, Action<bool> callback)
{
var alert = new AlertDialog.Builder(Android.App.Application.Context);
alert.SetTitle(title);
alert.SetMessage(content);
alert.SetNegativeButton(cancelButton, (sender, e) =>
{
callback(false);
_openDialogs.Remove((AlertDialog)sender);
});
alert.SetPositiveButton(okButton, (sender, e) =>
{
callback(true);
_openDialogs.Remove((AlertDialog)sender);
});
Device.BeginInvokeOnMainThread(() =>
{
var dialog = alert.Show();
_openDialogs.Add(dialog);
dialog.SetCanceledOnTouchOutside(false);
dialog.SetCancelable(false);
});
return true;
}
}
so whenever the private method alert is called it throws an Exception like this:
Unhandled Exception:
Android.Views.WindowManagerBadTokenException: Unable to add window --
token null is not valid; is your activity running?
it can be corrected if I switch this line of code:
var alert = new AlertDialog.Builder(Android.App.Application.Context);
for this line of code:
var activity = (Activity)Forms.Context;
var alert = new AlertDialog.Builder(activity);
the problem of using this I get a Xamarin.Forms warning like this:
'Forms.Context' is obsolete: 'Context is obsolete as of version 2.5.
Please use a local context instead.'
and i'm a bit obsesive I dont like to have warning and try to maintain my code as updated as possible so, can somebody help me make this code work without needing to use obsolete code. because I found answers that just replacing (Activity)Forms.Context for Android.App.Application.Context would work, but in this case it isn't working at all.
hopefully someone can point me in the right direction because i haven't been able to find any documentation about this case specifically.
Problem is that Android.App.Application.Context is not always an Activity Context.
Xamarin removed this and added a new constructor for the Renderers which include the context. The problem comes in cases like this where you are working on something that is not a CustomRenderer.
For these cases, I use James' Plugin CurrentActivityPlugin which will keep track of the current activity for you. Find it here
Hope this helps.-

How to implement Play Install Referrer API in Android?

I want to implement Play Install Referrer API and I found document and I read that but I have have some confusion. First I have implemented all code provided by google. But I want to know which type of url I need to create so that user can click on link and go to play store and install my app and then I get the referral detail..
I use this code:
InstallReferrerClient mReferrerClient;
mReferrerClient = newBuilder(this).build();
mReferrerClient.startConnection(this);
#Override
public void onInstallReferrerSetupFinished ( int responseCode){
switch (responseCode) {
case InstallReferrerClient.InstallReferrerResponse.OK:
// Connection established
/* ReferrerDetails response = null;
try {
response = mReferrerClient.getInstallReferrer();
response.getInstallReferrer();
response.getReferrerClickTimestampSeconds();
response.getInstallBeginTimestampSeconds();
} catch (RemoteException e) {
e.printStackTrace();
}*/
break;
case InstallReferrerClient.InstallReferrerResponse.FEATURE_NOT_SUPPORTED:
// API not available on the current Play Store app
break;
case InstallReferrerClient.InstallReferrerResponse.SERVICE_UNAVAILABLE:
// Connection could not be established
break;
}
}
#Override
public void onInstallReferrerServiceDisconnected () {
}
But which type of link I create so user go to play store and after install play store referral api give me data..
Sample url - "https://play.google.com/store/apps/details?id=com.dummy.app&referrer=referralCode%3D311566%26source%3DFacebook+App"
When using the Google Play Referrer API -
InstallReferrerClient mReferrerClient;
mReferrerClient = newBuilder(this).build();
mReferrerClient.startConnection(this);
#Override
public void onInstallReferrerSetupFinished ( int responseCode){
switch (responseCode) {
case InstallReferrerClient.InstallReferrerResponse.OK:
// Connection established
/* ReferrerDetails response = null;
try {
response = mReferrerClient.getInstallReferrer();
response.getInstallReferrer();
response.getReferrerClickTimestampSeconds();
response.getInstallBeginTimestampSeconds();
} catch (RemoteException e) {
e.printStackTrace();
}*/
// End the connection once you get the data
referrerClient.endConnection();
break;
case InstallReferrerClient.InstallReferrerResponse.FEATURE_NOT_SUPPORTED:
// API not available on the current Play Store app
break;
case InstallReferrerClient.InstallReferrerResponse.SERVICE_UNAVAILABLE:
// Connection could not be established
break;
}
}
#Override
public void onInstallReferrerServiceDisconnected () {
}
getInstallReferrer()
will return String 'referralCode=311566&source=Facebook App'
play install referral library i wants to describe this in simple wording, being a developer you wants to know about these elements how much time you app bundle take to install on the user devices from play store, and referral url , referral click time and many others elements , google make it easy for you know you have to use play install referral library for this purpose.
add this dependency
implementation 'com.android.installreferrer:installreferrer:1.1'
you can follow the guidelines from here:
play installer referral guidelines
declare this variable in any java activity
InstallReferrerClient referrerClient;
in on create method use this code below :
referrerClient = InstallReferrerClient.newBuilder(this).build();
referrerClient.startConnection(new InstallReferrerStateListener() {
#Override
public void onInstallReferrerSetupFinished(int responseCode) {
switch (responseCode) {
case InstallReferrerClient.InstallReferrerResponse.OK:
// Connection established.
break;
case InstallReferrerClient.InstallReferrerResponse.FEATURE_NOT_SUPPORTED:
// API not available on the current Play Store app.
break;
case InstallReferrerClient.InstallReferrerResponse.SERVICE_UNAVAILABLE:
// Connection couldn't be established.
break;
}
}
#Override
public void onInstallReferrerServiceDisconnected() {
// Try to restart the connection on the next request to
// Google Play by calling the startConnection() method.
}
});
inside onInstallReferrerSetupFinished stabled you can get these data easily,you code will be after that like this
ReferrerDetails response = null;
try {
response = referrerClient.getInstallReferrer();
} catch (RemoteException e) {
e.printStackTrace();
}
String referrerUrl = response.getInstallReferrer();
long referrerClickTime = response.getReferrerClickTimestampSeconds();
long appInstallTime = response.getInstallBeginTimestampSeconds();
boolean instantExperienceLaunched = response.getGooglePlayInstantParam();
whole code will be like this
referrerClient = InstallReferrerClient.newBuilder(this).build();
referrerClient.startConnection(new InstallReferrerStateListener() {
#Override
public void onInstallReferrerSetupFinished(int responseCode) {
switch (responseCode) {
case InstallReferrerClient.InstallReferrerResponse.OK:
// Connection established.
ReferrerDetails response = null;
try {
response = referrerClient.getInstallReferrer();
} catch (RemoteException e) {
e.printStackTrace();
}
String referrerUrl = response.getInstallReferrer();
long referrerClickTime = response.getReferrerClickTimestampSeconds();
long appInstallTime = response.getInstallBeginTimestampSeconds();
boolean instantExperienceLaunched = response.getGooglePlayInstantParam();
break;
case InstallReferrerClient.InstallReferrerResponse.FEATURE_NOT_SUPPORTED:
// API not available on the current Play Store app.
break;
case InstallReferrerClient.InstallReferrerResponse.SERVICE_UNAVAILABLE:
// Connection couldn't be established.
break;
}
}
#Override
public void onInstallReferrerServiceDisconnected() {
// Try to restart the connection on the next request to
// Google Play by calling the startConnection() method.
}
});

Google Drive API implementation Xamarin Android

Our application should have the functionality to save Application files to Google Drive. Of course, using the local configured account.
From Android API i tried to figure out some clue. But android API with Xamarin implementation seems very tough for me.
I have installed Google Play Services- Drive from Xamarin Components but there are no examples listed from which we can refer the flow and functionality.
The basic steps (see the link below for full details):
Create GoogleApiClient with the Drive API and Scope
Try to connect (login) the GoogleApiClient
The first time you try to connect it will fail as the user has not selected a Google Account that should be used
Use StartResolutionForResult to handle this condition
When GoogleApiClient is connected
Request a Drive content (DriveContentsResult) to write the file contents to.
When the result is obtained, write data into the Drive content.
Set the metadata for the file
Create the Drive-based file with the Drive content
Note: This example assumes that you have Google Drive installed on your device/emulator and you have registered your app in Google's Developer API Console with the Google Drive API Enabled.
C# Example:
[Activity(Label = "DriveOpen", MainLauncher = true, Icon = "#mipmap/icon")]
public class MainActivity : Activity, GoogleApiClient.IConnectionCallbacks, IResultCallback, IDriveApiDriveContentsResult
{
const string TAG = "GDriveExample";
const int REQUEST_CODE_RESOLUTION = 3;
GoogleApiClient _googleApiClient;
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.Main);
Button button = FindViewById<Button>(Resource.Id.myButton);
button.Click += delegate
{
if (_googleApiClient == null)
{
_googleApiClient = new GoogleApiClient.Builder(this)
.AddApi(DriveClass.API)
.AddScope(DriveClass.ScopeFile)
.AddConnectionCallbacks(this)
.AddOnConnectionFailedListener(onConnectionFailed)
.Build();
}
if (!_googleApiClient.IsConnected)
_googleApiClient.Connect();
};
}
protected void onConnectionFailed(ConnectionResult result)
{
Log.Info(TAG, "GoogleApiClient connection failed: " + result);
if (!result.HasResolution)
{
GoogleApiAvailability.Instance.GetErrorDialog(this, result.ErrorCode, 0).Show();
return;
}
try
{
result.StartResolutionForResult(this, REQUEST_CODE_RESOLUTION);
}
catch (IntentSender.SendIntentException e)
{
Log.Error(TAG, "Exception while starting resolution activity", e);
}
}
public void OnConnected(Bundle connectionHint)
{
Log.Info(TAG, "Client connected.");
DriveClass.DriveApi.NewDriveContents(_googleApiClient).SetResultCallback(this);
}
protected override void OnActivityResult(int requestCode, Result resultCode, Intent data)
{
base.OnActivityResult(requestCode, resultCode, data);
if (requestCode == REQUEST_CODE_RESOLUTION)
{
switch (resultCode)
{
case Result.Ok:
_googleApiClient.Connect();
break;
case Result.Canceled:
Log.Error(TAG, "Unable to sign in, is app registered for Drive access in Google Dev Console?");
break;
case Result.FirstUser:
Log.Error(TAG, "Unable to sign in: RESULT_FIRST_USER");
break;
default:
Log.Error(TAG, "Should never be here: " + resultCode);
return;
}
}
}
void IResultCallback.OnResult(Java.Lang.Object result)
{
var contentResults = (result).JavaCast<IDriveApiDriveContentsResult>();
if (!contentResults.Status.IsSuccess) // handle the error
return;
Task.Run(() =>
{
var writer = new OutputStreamWriter(contentResults.DriveContents.OutputStream);
writer.Write("Stack Overflow");
writer.Close();
MetadataChangeSet changeSet = new MetadataChangeSet.Builder()
.SetTitle("New Text File")
.SetMimeType("text/plain")
.Build();
DriveClass.DriveApi
.GetRootFolder(_googleApiClient)
.CreateFile(_googleApiClient, changeSet, contentResults.DriveContents);
});
}
public void OnConnectionSuspended(int cause)
{
throw new NotImplementedException();
}
public IDriveContents DriveContents
{
get
{
throw new NotImplementedException();
}
}
public Statuses Status
{
get
{
throw new NotImplementedException();
}
}
}
Ref: https://developers.google.com/drive/android/create-file

OData Connection in Xamarin Form

My code crashes and gives the following error on simulator. It attempts to run the try block in the GetDataFromOdataService() method and throws an error and also issue an alert. I am using Xamarin.Form
using Simple.OData.Client;
using System.Threading.Tasks;
private ODataClient mODataClient;
protected async override void OnAppearing ()
{
base.OnAppearing ();
await InitializeDataService ();
await GetDataFromOdataService();
}
public async Task <bool> InitializeDataService(){
try {
mODataClient = new ODataClient ("http://services.odata.org/Northwind/Northwind.svc/");
}
catch {
await DisplayAlert("Error", "Connection Error", "OK", "Cancel");
System.Diagnostics.Debug.WriteLine("ERROR!");
}
return true;
}
public async Task<bool> GetDataFromOdataService (){
try {
myCustomers= await mODataClient.For("Customers").Top(10).FindEntriesAsync();
}
catch {
await DisplayAlert("Error", "Connection Error", "OK", "Cancel");
System.Diagnostics.Debug.WriteLine("ERROR!");
}
return true;
}
Couple issues:-
In the constructor it was doing var list = new ListView() which constrained it locally than setting the class level scope variable. This was therefore adjusted to list = new ListView().
The other thing, was in the GetTheData function where the items source was being assigned as list.ItemsSource = myList; where it needed changing to list.ItemsSource = Customers;.
I've repackaged the zip file up and sent to you. Let me know if this works for you? You should now be able to see all your customers in the ListView.

Breaking on exception: String expected

When I run my code I get:
Breaking on exception: String expected
What I am trying to do is connect to my server using a websocket. However, it seems that no matter if my server is online or not the client still crashes.
My code:
import 'dart:html';
WebSocket serverConn;
int connectionAttempts;
TextAreaElement inputField = querySelector("#inputField");
String key;
void submitMessage(Event e) {
if (serverConn.readyState == WebSocket.OPEN) {
querySelector("#chatLog").text = inputField.value;
inputField.value = "";
}
}
void recreateConnection(Event e) {
connectionAttempts++;
if (connectionAttempts <= 5) {
inputField.value = "Connection failed, reconnecting. Attempt" + connectionAttempts.toString() + "out of 5";
serverConn = new WebSocket("ws://127.0.0.1:8887");
serverConn.onClose.listen(recreateConnection);
serverConn.onError.listen(recreateConnection);
} else {
inputField.value = "Connections ran out, please refresh site";
}
}
void connected(Event e) {
serverConn.sendString(key);
if (serverConn.readyState == WebSocket.OPEN) {
inputField.value = "CONNECTED!";
inputField.readOnly = false;
}
}
void main() {
serverConn = new WebSocket("ws://127.0.0.1:8887");
serverConn.onClose.listen(recreateConnection);
serverConn.onError.listen(recreateConnection);
serverConn.onOpen.listen(connected);
//querySelector("#inputField").onInput.listen(submitMessage);
querySelector("#sendInput").onClick.listen(submitMessage);
}
My Dart Editor says nothing about where the problem comes from nor does it give any warning until run-time.
You need to initialize int connectionAttempts; with a valid value;
connectionAttempts++; fails with an exception on null.
You also need an onMessage handler to receive messages.
serverConn.onMessage.listen((MessageEvent e) {
recreateConnection should register an onOpen handler as well.
After serverConn = new WebSocket the listener registered in main() will not work
If you register a listener where only one single event is expected you can use first instead of listen
serverConn.onOpen.first.then(connected);
According to #JAre s comment.
Try to use a hardcoded string
querySelector("#chatLog").text = 'someValue';
to ensure this is not the culprit.

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