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++ // Copyright (C) 2016 basysKom GmbH, author Bernd Lamecker <bernd.lamecker@basyskom.com>
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
++
++ /*!
++ \example chatclient-qml
++ \title Qt WebChannel ChatClient QML Application
++ \ingroup qtwebchannel-examples
++ \brief A QML client that communicates over a WebSocket with a QWebChannel server.
++ \examplecategory {Web Technologies}
++ \meta tag {rpc,network}
++
++ \image chatclient-qml.png
++ {Small Login window with a Login button in front of a Hello World
++ window}
++
++ \e{ChatClient QML} provides a simple QWebChannel client implemented using JavaScript and QML.
++
++ \section1 Implementing a Web Channel Client in QML
++
++ This example shows how you can use the basic elements with the client JavaScript
++ implementation of QWebChannel, like connecting to signals (\c newMessage),
++ calling slots (\c sendMessage), and handling property changes (\c userList).
++
++ The client initializes a \l [QML] WebSocket connection to the chat server at port
++ 12345 on localhost. When the WebSocket opens, a WebChannel object is created, taking
++ the WebSocket as first argument and a callback function as the second argument. When
++ the callback is called, the client receives an object named \c chatserver,
++ containing all the necessary signals, slots, and properties for implementing a chat
++ client. The callback function connects \c userListChanged, \c newMessage, and
++ \c keepAlive on the \c chatserver object with separate functions handling those
++ signals, and then it calls \c show on \c loginWindow.
++
++ The \c Window with \c loginWindow as id handles the login procedure. It contains a
++ \c LoginForm defined in LoginForm.ui.qml. When you press the button, it calls
++ the \c login function on the \c chatserver object with the login name and and a
++ callback function as arguments. This callback function handles both if the login
++ succeeds or fails.
++
++ After login, the client uses a \c MainForm, defined in MainForm.ui.qml, with
++ \c mainUi as id, to post messages using the \c sendMessage slot, read messages
++ using the \c newMessage signal, and to view the names of all connected users
++ using the \c userList property. Also, the client responds to the server's
++ \c keepAlive signal in order for the server to detect disconnected clients
++ and remove them from the \c userList property.
++
++ The client is able to work with the \l{Qt WebChannel ChatServer Example}.
++
++ \sa {Qt WebChannel ChatServer Example}, {Qt WebChannel ChatClient HTML Example}
++
++ */