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| /*! |
| \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. |
| */ |