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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
\example widgets/digitalclock
\title Digital Clock Example
\ingroup examples-widgets
\brief The Digital Clock example shows how to use QLCDNumber to display a
number with LCD-like digits.
\borderedimage digitalclock-example.png
\caption 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 widgets/digitalclock/digitalclock.h 0
\section1 DigitalClock Class Implementation
\snippet 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 widgets/digitalclock/digitalclock.cpp 1
\snippet 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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