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/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
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** contained in the Technology Preview License Agreement accompanying
** this package.
**
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** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
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**
** In addition, as a special exception, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.1, included in the file LGPL_EXCEPTION.txt in this
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****************************************************************************/
/*!
\example widgets/digitalclock
\title Digital Clock Example
The Digital Clock example shows how to use QLCDNumber to display a
number with LCD-like digits.
\image digitalclock-example.png Screenshot of the Digital Clock example
This example also demonstrates how QTimer can be used to update a widget
at regular intervals.
\section1 DigitalClock Class Definition
The \c DigitalClock class provides a clock widget showing the time with
hours and minutes separated by a blinking colon. We subclass QLCDNumber
and implement a private slot called \c showTime() to update the clock
display:
\snippet examples/widgets/digitalclock/digitalclock.h 0
\section1 DigitalClock Class Implementation
\snippet examples/widgets/digitalclock/digitalclock.cpp 0
In the constructor, we first change the look of the LCD numbers. The
QLCDNumber::Filled style produces raised segments filled with the
foreground color (typically black). We also set up a one-second timer
to keep track of the current time, and we connect
its \l{QTimer::timeout()}{timeout()} signal to the private \c showTime() slot
so that the display is updated every second. Then, we
call the \c showTime() slot; without this call, there would be a one-second
delay at startup before the time is shown.
\snippet examples/widgets/digitalclock/digitalclock.cpp 1
\snippet examples/widgets/digitalclock/digitalclock.cpp 2
The \c showTime() slot is called whenever the clock display needs
to be updated.
The current time is converted into a string with the format "hh:mm".
When QTime::second() is a even number, the colon in the string is
replaced with a space. This makes the colon appear and vanish every
other second.
Finally, we call QLCDNumber::display() to update the widget.
*/
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