How to use QLCDNumber in Qt

Article Metadata

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Code Example

Source file: Media:Lcdnumber.zip

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Tested with

Devices(s): Emulator (S60 5th edition)

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Compatibility

Platform(s): Qt

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Article

Keywords: QLCDNumber,QSpinBox

Created: james1980 (03 Jan 2008)

Last edited: hamishwillee (11 Oct 2012)

Introduction

This article shows the use of LCD number to display some number. For example it can be use to display a score while designing a game.

Various Functions

• This line create a object of the LCDNumber.

QLCDNumber* number = new QLCDNumber(this);

• To specify the segment display style of the LCD number. Qt support the three different filled style i.e. Filled,Outline and Flat.

number->setSegmentStyle(QLCDNumber::Filled);

• To specify the number of LCD digits that would be display.This function specify the mode of the LCD. Various supported modes are Hex,Dec,Bin and Oct.

number->setMode(QLCDNumber::Hex);

Related Link

• Check this digital clock example that shows the use of the QLCDNumber.

• Read more about QLCDNumber

• Download Lcdnumber.zip

Source Code

Header file

#ifndef LCDNUMBER_H
#define LCDNUMBER_H
 
#include <QWidget>
#include <QLCDNumber>
#include <QSpinBox>
#include <QVBoxLayout>
 
class lcdnumber : public QWidget
{
    Q_OBJECT
 
public:
	lcdnumber(QWidget *parent = 0);
    ~lcdnumber();
private:
    QVBoxLayout* layout;
    QLCDNumber* number;
    QSpinBox* spin;
 
};
 
#endif // LCDNUMBER_H

Source file

#include "lcdnumber.h"
 
lcdnumber::lcdnumber(QWidget *parent)
    : QWidget(parent)
{
 
        setWindowTitle(("LCD Number"));
	layout = new QVBoxLayout(this);
	number = new QLCDNumber(this);
	spin = new QSpinBox(this);
	spin->setMaximum(9);
	spin->setMinimum(0);
 
	connect(spin, SIGNAL(valueChanged(int)), number, SLOT(display(int)));
	layout->addWidget(spin,Qt::AlignCenter);
 
	layout->addWidget(number,Qt::AlignCenter);
	showMaximized();
}
 
lcdnumber::~lcdnumber()
{
 
}

Screenshot