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diff --git a/examples/serialport/doc/terminal.qdoc b/examples/serialport/doc/terminal.qdoc new file mode 100644 index 00000000..b432390b --- /dev/null +++ b/examples/serialport/doc/terminal.qdoc @@ -0,0 +1,144 @@ +/**************************************************************************** +** +** Copyright (C) 2011 - 2012 Denis Shienkov <denis.shienkov@gmail.com> +** Contact: http://www.qt-project.org/legal +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:FDL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and Digia. For licensing terms and +** conditions see http://qt.digia.com/licensing. For further information +** use the contact form at http://qt.digia.com/contact-us. +** +** GNU Free Documentation License Usage +** Alternatively, this file may be used under the terms of the GNU Free +** Documentation License version 1.3 as published by the Free Software +** Foundation and appearing in the file included in the packaging of +** this file. Please review the following information to ensure +** the GNU Free Documentation License version 1.3 requirements +** will be met: http://www.gnu.org/copyleft/fdl.html. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \example terminal + \title Terminal Example + \ingroup qtserialport-examples + + The Terminal example shows how to create a terminal for a simple serial + interface by using Qt Serial Port. + + \image terminal-example.png Screenshot of the Terminal example + + This example shows the main features of the QSerialPort class, like + configuration, I/O implementation and so forth. Also, the class + QSerialPortInfo is invoked to display information about the serial ports + available in the system. + + QSerialPort supports two general programming approaches: + + \list + + \li \e{The asynchronous (non-blocking) approach.} Operations are scheduled + and performed when the control returns to Qt's event loop. QSerialPort emits + a signal when the operation is finished. For example, QSerialPort::write() + returns immediately. When the data is sent to the serial port, QSerialPort + emits \l{QSerialPort::bytesWritten()}{bytesWritten()}. + + \li \e{The synchronous (blocking) approach.} In non-GUI and multithreaded + applications, the \c waitFor...() functions can be called (i.e. + QSerialPort::waitReadyRead()) to suspend the calling thread until the + operation has completed. + + \endlist + + In this example, the asynchronous approach is demonstrated. + + Our example contains some GUI widgets: + + \list + + \li \l{terminal/mainwindow.cpp}{MainWindow} - is the main application + window that contains all the working logic for the serial port programming, + including configuration, I/O processing and so forth, while inheriting the + QMainWindow. + + \li \l{terminal/console.cpp}{Console} - is the central widget of the + main window, displaying the transmitted or received data. The widget is + derived from the QPlainTextEdit class. + + \li \l{terminal/settingsdialog.cpp}{SettingsDialog} - is a dialog + for configuring the serial port, as well as for displaying the available + serial ports and information about them. + + \endlist + + The serial port is instantiated in the \l{terminal/mainwindow.cpp}{MainWindow} + constructor. The main widget is passed as the parent, so the object deletion + happens automatically according to the the parent and child mechanism in Qt: + + \snippet terminal/mainwindow.cpp 0 + \dots + \snippet terminal/mainwindow.cpp 1 + + The only QSerialPort signal invoked in this example is + QSerialPort::readyRead(), which shows that new data has been received and + hence available: + + \dots + \snippet terminal/mainwindow.cpp 2 + \dots + \snippet terminal/mainwindow.cpp 3 + + Clicking on the \b{Connect} button invokes the \c openSerialPort() slot: + + \snippet terminal/mainwindow.cpp 4 + + In this slot, the settings are read from \l{terminal/settingsdialog.cpp} + {SettingsDialog} and an attempt is made to open and initialize the serial + port accordingly. If successful, the status bar displays a message that the + opening was successful with the given configuration; otherwise, a messagebox + is displayed with the appropriate error code and message. If the serial port + settings have never been called + \l{terminal/settingsdialog.cpp}{SettingsDialog}, then the terminal + attempts to open the port with the default settings: 9600 8N1. + + Clicking on the \b{Disconnect} button invokes the \c closeSerialPort() + slot: + + \snippet terminal/mainwindow.cpp 5 + + In this case, handled by the closure of the serial port. + + Typing characters in the console invokes the \c writeData() slot: + + \snippet terminal/mainwindow.cpp 6 + + This slot sends the characters typed in the given + \l{terminal/console.cpp}{Console} widget to the serial port. + + When the serial port receives new data, the signal + \l{QTcpSocket::readyRead()}{readyRead()} is emitted, and that signal is + connected to the \c MainWindow::readData() slot: + + \snippet terminal/mainwindow.cpp 7 + + This slot reads the data from the serial port and displays that in the + \l{terminal/console.cpp}{Console} widget. + + Clicking on the \b{Configure} button invokes the \c show() slot which + belongs to the \l{terminal/settingsdialog.cpp}{SettingsDialog} + widget. + + This method displays the \l{terminal/settingsdialog.cpp}{SettingsDialog} + in which the user can choose the desired serial port, see the information + about the selected port, and set the desired parameters of the given serial + port. + + \sa {Blocking Simple Terminal Example} +*/ |