QLCDNumber(3qt)

📦 version 3.3.8b, in fedora 43, fedora 44

✨ QLCDNumber(3qt) ✨

okay bestie, welcome to the QLCDNumber page from the 3qt manual 💖 this is the widget that gives you the little calculator-screen digits, and honestly? she's a legend. let's get into it.

🌸 NAME 🌸

QLCDNumber — displays a number with LCD-like digits. that's the whole job. she shows numbers. slay. 🔢

🎀 SYNOPSIS 🎀

#include <qlcdnumber.h>

Inherits QFrame. (yes, she's a frame girlie, keep up 💅)

👑 Public Members

QLCDNumber ( QWidget * parent = 0, const char * name = 0 )
QLCDNumber ( uint numDigits, QWidget * parent = 0, const char * name = 0 )
~QLCDNumber ()
enum Mode { Hex, Dec, Oct, Bin, HEX = Hex, DEC = Dec, OCT = Oct, BIN = Bin }
enum SegmentStyle { Outline, Filled, Flat }
bool smallDecimalPoint () const
int numDigits () const
virtual void setNumDigits ( int nDigits )
bool checkOverflow ( double num ) const
bool checkOverflow ( int num ) const
Mode mode () const
virtual void setMode ( Mode )
SegmentStyle segmentStyle () const
virtual void setSegmentStyle ( SegmentStyle )
double value () const
int intValue () const

🌟 Public Slots

void display ( const QString & s )
void display ( int num )
void display ( double num )
virtual void setHexMode ()
virtual void setDecMode ()
virtual void setOctMode ()
virtual void setBinMode ()
virtual void setSmallDecimalPoint ( bool )

🔔 Signals

void overflow ()

💜 Properties

int intValue — the displayed value rounded to the nearest integer
Mode mode — the current display mode (number base)
int numDigits — the current number of digits displayed
SegmentStyle segmentStyle — the style of the LCDNumber
bool smallDecimalPoint — the style of the decimal point
double value — the displayed value

🛡 Protected Members

virtual void drawContents ( QPainter * p )

🌈 DESCRIPTION 🌈

The QLCDNumber widget displays a number with LCD-like digits. iconic behavior, no notes ✨

It can display a number in just about any size. It can display decimal, hexadecimal, octal or binary numbers. It is easy to connect to data sources using the display() slot, which is overloaded to take any of five argument types. five. argument. types. she's flexible like that 💁‍♀️

There are also slots to change the base with setMode() and the decimal point with setSmallDecimalPoint().

QLCDNumber emits the overflow() signal when it is asked to display something beyond its range. The range is set by setNumDigits(), but setSmallDecimalPoint() also influences it. If the display is set to hexadecimal, octal or binary, the integer equivalent of the value is displayed.

These digits and other symbols can be shown: 0/O, 1, 2, 3, 4, 5/S, 6, 7, 8, 9/g, minus, decimal point, A, B, C, D, E, F, h, H, L, o, P, r, u, U, Y, colon, degree sign (which is specified as single quote in the string) and space. QLCDNumber substitutes spaces for illegal characters. so if you try to be cute with a character she doesn't know, she just. blanks you. respectfully. 💀

It is not possible to retrieve the contents of a QLCDNumber object, although you can retrieve the numeric value with value(). If you really need the text, we recommend that you connect the signals that feed the display() slot to another slot as well and store the value there. tl;dr: she does not do receipts, back up your own data bestie

Incidentally, QLCDNumber is the very oldest part of Qt, tracing back to a BASIC program on the Sinclair Spectrum. she's literally the OG, the founding mother, the main character of Qt history 👑

[Image Omitted]

See also QLabel, QFrame, and Basic Widgets.

📚 Member Type Documentation 📚

🧮 QLCDNumber::Mode

This type determines how numbers are shown.

QLCDNumber::Hex — Hexadecimal
QLCDNumber::Dec — Decimal
QLCDNumber::Oct — Octal
QLCDNumber::Bin — Binary

If the display is set to hexadecimal, octal or binary, the integer equivalent of the value is displayed.

🎨 QLCDNumber::SegmentStyle

This type determines the visual appearance of the QLCDNumber widget.

QLCDNumber::Outline — gives raised segments filled with the background brush.
QLCDNumber::Filled — gives raised segments filled with the foreground brush.
QLCDNumber::Flat — gives flat segments filled with the foreground brush.

🛠 MEMBER FUNCTION DOCUMENTATION 🛠

`QLCDNumber::QLCDNumber ( QWidget * parent = 0, const char * name = 0 )`

Constructs an LCD number, sets the number of digits to 5, the base to decimal, the decimal point mode to 'small' and the frame style to a raised box. The segmentStyle() is set to Outline.

The parent and name arguments are passed to the QFrame constructor.

See also numDigits and smallDecimalPoint.

`QLCDNumber::QLCDNumber ( uint numDigits, QWidget * parent = 0, const char * name = 0 )`

Constructs an LCD number, sets the number of digits to numDigits, the base to decimal, the decimal point mode to 'small' and the frame style to a raised box. The segmentStyle() is set to Outline.

The parent and name arguments are passed to the QFrame constructor.

See also numDigits and smallDecimalPoint.

`QLCDNumber::~QLCDNumber ()`

Destroys the LCD number. bye girl, you served 🫶

`bool QLCDNumber::checkOverflow ( double num ) const`

Returns TRUE if num is too big to be displayed in its entirety; otherwise returns FALSE.

See also display(), numDigits, and smallDecimalPoint.

`bool QLCDNumber::checkOverflow ( int num ) const`

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

Returns TRUE if num is too big to be displayed in its entirety; otherwise returns FALSE.

See also display(), numDigits, and smallDecimalPoint.

`void QLCDNumber::display ( const QString & s )` — [slot]

Displays the number represented by the string s.

This version of the function disregards mode() and smallDecimalPoint(). she's going rogue, she's doing her own thing, no cap.

Examples:

`void QLCDNumber::display ( int num )` — [slot]

Sets the displayed value rounded to the nearest integer to num. See the "intValue" property for details.

`void QLCDNumber::display ( double num )` — [slot]

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

Displays the number num.

`void QLCDNumber::drawContents ( QPainter * p )` — [virtual protected]

Draws the LCD number using painter p. This function is called from QFrame::paintEvent().

Reimplemented from QFrame.

`int QLCDNumber::intValue () const`

Returns the displayed value rounded to the nearest integer. See the "intValue" property for details.

`Mode QLCDNumber::mode () const`

Returns the current display mode (number base). See the "mode" property for details.

`int QLCDNumber::numDigits () const`

Returns the current number of digits displayed. See the "numDigits" property for details.

`void QLCDNumber::overflow ()` — [signal]

This signal is emitted whenever the QLCDNumber is asked to display a too-large number or a too-long string. she's screaming, bestie, she's at capacity 😭

It is never emitted by setNumDigits().

`SegmentStyle QLCDNumber::segmentStyle () const`

Returns the style of the LCDNumber. See the "segmentStyle" property for details.

`void QLCDNumber::setBinMode ()` — [virtual slot]

Calls setMode( BIN ). Provided for convenience (e.g. for connecting buttons to it).

See also mode, setHexMode(), setDecMode(), setOctMode(), and mode.

`void QLCDNumber::setDecMode ()` — [virtual slot]

Calls setMode( DEC ). Provided for convenience (e.g. for connecting buttons to it).

See also mode, setHexMode(), setOctMode(), setBinMode(), and mode.

`void QLCDNumber::setHexMode ()` — [virtual slot]

Calls setMode( HEX ). Provided for convenience (e.g. for connecting buttons to it).

See also mode, setDecMode(), setOctMode(), setBinMode(), and mode.

`void QLCDNumber::setMode ( Mode )` — [virtual]

Sets the current display mode (number base). See the "mode" property for details.

`void QLCDNumber::setNumDigits ( int nDigits )` — [virtual]

Sets the current number of digits displayed to nDigits. See the "numDigits" property for details.

`void QLCDNumber::setOctMode ()` — [virtual slot]

Calls setMode( OCT ). Provided for convenience (e.g. for connecting buttons to it).

See also mode, setHexMode(), setDecMode(), setBinMode(), and mode.

`void QLCDNumber::setSegmentStyle ( SegmentStyle )` — [virtual]

Sets the style of the LCDNumber. See the "segmentStyle" property for details.

`void QLCDNumber::setSmallDecimalPoint ( bool )` — [virtual slot]

Sets the style of the decimal point. See the "smallDecimalPoint" property for details.

`bool QLCDNumber::smallDecimalPoint () const`

Returns the style of the decimal point. See the "smallDecimalPoint" property for details.

`double QLCDNumber::value () const`

Returns the displayed value. See the "value" property for details.

💖 Property Documentation 💖

`int intValue`

This property holds the displayed value rounded to the nearest integer.

This property corresponds to the nearest integer to the current value displayed by the LCDNumber. This is the value used for hexadecimal, octal and binary modes.

If the displayed value is not a number, the property has a value of 0.

Set this property's value with display() and get this property's value with intValue().

`Mode mode`

This property holds the current display mode (number base).

Corresponds to the current display mode, which is one of BIN, OCT, DEC (the default) and HEX. DEC mode can display floating point values, the other modes display the integer equivalent.

See also smallDecimalPoint, setHexMode(), setDecMode(), setOctMode(), and setBinMode().

Set this property's value with setMode() and get this property's value with mode().

`int numDigits`

This property holds the current number of digits displayed.

Corresponds to the current number of digits. If QLCDNumber::smallDecimalPoint is FALSE, the decimal point occupies one digit position.

`SegmentStyle segmentStyle`

This property holds the style of the LCDNumber.

<center>.nf</center>

Outline and Filled will additionally use QColorGroup::light() and QColorGroup::dark() for shadow effects.

Set this property's value with setSegmentStyle() and get this property's value with segmentStyle().

`bool smallDecimalPoint`

This property holds the style of the decimal point.

If TRUE the decimal point is drawn between two digit positions. Otherwise it occupies a digit position of its own, i.e. is drawn in a digit position. The default is FALSE.

The inter-digit space is made slightly wider when the decimal point is drawn between the digits.

`double value`

This property holds the displayed value.

This property corresponds to the current value displayed by the LCDNumber.

If the displayed value is not a number, the property has a value of 0.

Set this property's value with display() and get this property's value with value().

okay bestie that's part 1 and there is absolutely more where that came from, keep scrolling 👀🧚‍♀️

👀 SEE ALSO 👀

bestie if u wanna go deeper (and honestly, same) here's where the lore lives:

http://doc.trolltech.com/qlcdnumber.html — the full glow-up of this exact widget ✨
http://www.trolltech.com/faq/tech.html — the FAQ, aka the "wait why is it doing that" hotline 💅

📜 COPYRIGHT 📜

and fr fr, go read the license file included in the distribution for the complete license statement — it's giving required reading, no skimming bestie 🫶

✍️ AUTHOR ✍️

Generated automatically from the source code.

not a human, not a ghostwriter, just the build system doing its lil thing 🤖💖

🐛 BUGS 🐛

okay so if u find a bug in Qt 😭 pls pls pls report it the way they describe over at:

http://doc.trolltech.com/bughowto.html

Good bug reports help us to help you. Thank you. — and that's not me being sarcastic, that's literally the manpage being wholesome 🥹💖 a well-written bug report is genuinely main character energy and we are obsessed.

🚨 real talk: the definitive Qt documentation is provided in HTML format. It lives at $QTDIR/doc/html and u can read it with Qt Assistant or with a web browser. This man page is provided as a convenience for those users who prefer man pages — although this format is not officially supported by Trolltech. so like… it's the cute fan-made version, not the canon text, iykyk 🙈

aaaand if u find errors in this manual page specifically? spill the tea to qt-bugs@trolltech.com 💌

when u do, pls include:

the name of the manual page — qlcdnumber.3qt
the Qt version — 3.3.8

that's it, that's the whole vibe check 🌈⭐

and that's a wrap on QLCDNumber(3qt) bestie!! 🎀 u now know every single flag, mode, signal and slot and honestly? slay. go make some seven-segment digits pop off ✨💅

source: Trolltech AS — dated 2 February 2007 — page QLCDNumber(3qt) 🌸🦋

📦 where this page comes from

fedora 43: qt3-devel-docs 3.3.8b-102.fc43 · QPL-1.0 OR GPL-2.0-only OR GPL-3.0-only
fedora 44: qt3-devel-docs 3.3.8b-103.fc44 · QPL-1.0 OR GPL-2.0-only OR GPL-3.0-only
💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash on 2026-10-14: a language model's rewrite of the original, under its terms

QLCDNumber(3qt)

✨ QLCDNumber(3qt) ✨

🌸 NAME 🌸

🎀 SYNOPSIS 🎀

👑 Public Members

🌟 Public Slots

🔔 Signals

💜 Properties

🛡 Protected Members

🌈 DESCRIPTION 🌈

📚 Member Type Documentation 📚

🧮 QLCDNumber::Mode

🎨 QLCDNumber::SegmentStyle

🛠 MEMBER FUNCTION DOCUMENTATION 🛠

QLCDNumber::QLCDNumber ( QWidget * parent = 0, const char * name = 0 )

QLCDNumber::QLCDNumber ( uint numDigits, QWidget * parent = 0, const char * name = 0 )

QLCDNumber::~QLCDNumber ()

bool QLCDNumber::checkOverflow ( double num ) const

bool QLCDNumber::checkOverflow ( int num ) const

void QLCDNumber::display ( const QString & s ) — [slot]

void QLCDNumber::display ( int num ) — [slot]

void QLCDNumber::display ( double num ) — [slot]

void QLCDNumber::drawContents ( QPainter * p ) — [virtual protected]

int QLCDNumber::intValue () const

Mode QLCDNumber::mode () const

int QLCDNumber::numDigits () const

void QLCDNumber::overflow () — [signal]

SegmentStyle QLCDNumber::segmentStyle () const

void QLCDNumber::setBinMode () — [virtual slot]

void QLCDNumber::setDecMode () — [virtual slot]

void QLCDNumber::setHexMode () — [virtual slot]

void QLCDNumber::setMode ( Mode ) — [virtual]

void QLCDNumber::setNumDigits ( int nDigits ) — [virtual]

void QLCDNumber::setOctMode () — [virtual slot]

void QLCDNumber::setSegmentStyle ( SegmentStyle ) — [virtual]

void QLCDNumber::setSmallDecimalPoint ( bool ) — [virtual slot]

bool QLCDNumber::smallDecimalPoint () const

double QLCDNumber::value () const