doc/src/examples/digitalclock.qdoc
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+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
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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.
+*/