qmlchatclient.qml Example File

chatclient-qml/qmlchatclient.qml
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 ** Copyright (C) 2016 basysKom GmbH, author Bernd Lamecker <bernd.lamecker@basyskom.com>
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 ** This file is part of the QtWebChannel module of the Qt Toolkit.
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 import QtQuick 2.2
 import QtQuick.Dialogs 1.2
 import QtQuick.Controls 2.0
 import QtQuick.Window 2.0
 import QtQuick.Layouts 1.1
 import Qt.WebSockets 1.0
 import "qwebchannel.js" as WebChannel

 ApplicationWindow {
     id: root

     property var channel
     property string loginName: loginUi.userName.text

     title: "Chat client"
     width: 640
     height: 480
     visible: true

     WebSocket {
         id: socket

         // the following three properties/functions are required to align the QML WebSocket API
         // with the HTML5 WebSocket API.
         property var send: function(arg) {
             sendTextMessage(arg);
         }

         onTextMessageReceived: {
             onmessage({data: message});
         }

         property var onmessage

         active: true
         url: "ws://localhost:12345"

         onStatusChanged: {
             switch (socket.status) {
             case WebSocket.Error:
                 errorDialog.text = "Error: " + socket.errorString;
                 errorDialog.visible = true;
                 break;
             case WebSocket.Closed:
                 errorDialog.text = "Error: Socket at " + url + " closed.";
                 errorDialog.visible = true;
                 break;
             case WebSocket.Open:
                 //open the webchannel with the socket as transport
                 new WebChannel.QWebChannel(socket, function(ch) {
                     root.channel = ch;

                     //connect to the changed signal of the userList property
                     ch.objects.chatserver.userListChanged.connect(function(args) {
                         mainUi.userlist.text = '';
                         ch.objects.chatserver.userList.forEach(function(user) {
                             mainUi.userlist.text += user + '\n';
                         });
                     });

                     //connect to the newMessage signal
                     ch.objects.chatserver.newMessage.connect(function(time, user, message) {
                         var line = "[" + time + "] " + user + ": " + message + '\n';
                         mainUi.chat.text = mainUi.chat.text + line;
                     });

                     //connect to the keep alive signal
                     ch.objects.chatserver.keepAlive.connect(function(args) {
                         if (loginName !== '')
                             //and call the keep alive response method as an answer
                             ch.objects.chatserver.keepAliveResponse(loginName);
                     });
                 });

                 loginWindow.show();
                 break;
             }
         }
     }

     MainForm {
         id: mainUi
         anchors.fill: parent

         Connections {
             target: mainUi.message
             onEditingFinished: {
                 if (mainUi.message.text.length) {
                     //call the sendMessage method to send the message
                     root.channel.objects.chatserver.sendMessage(loginName,
                                                                 mainUi.message.text);
                 }
                 mainUi.message.text = '';
             }
         }
     }

     Window {
         id: loginWindow

         title: "Login"
         modality: Qt.ApplicationModal
         width: 300
         height: 200

         LoginForm {
             id: loginUi
             anchors.fill: parent

             nameInUseError.visible: false

             Connections {
                 target: loginUi.loginButton

                 onClicked: {
                     //call the login method
                     root.channel.objects.chatserver.login(loginName, function(arg) {
                         //check the return value for success
                         if (arg === true) {
                             loginUi.nameInUseError.visible = false;
                             loginWindow.close();
                         } else {
                             loginUi.nameInUseError.visible = true;
                         }
                     });
                 }
             }
         }
     }

     MessageDialog {
         id: errorDialog

         icon: StandardIcon.Critical
         standardButtons: StandardButton.Close
         title: "Chat client"

         onAccepted: {
             Qt.quit();
         }
         onRejected: {
             Qt.quit();
         }
     }
 }