qlcdnumber.cpp

qtopia-phone-2.2.0下公共的控件实现源代码。

/****************************************************************************
** $Id: qt/src/widgets/qlcdnumber.cpp   2.3.12   edited 2005-10-27 $
**
** Implementation of QLCDNumber class
**
** Created : 940518
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of the widgets module of the Qt GUI Toolkit.
**
** This file may be distributed under the terms of the Q Public License
** as defined by Trolltech AS of Norway and appearing in the file
** LICENSE.QPL included in the packaging of this file.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
** licenses may use this file in accordance with the Qt Commercial License
** Agreement provided with the Software.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://www.trolltech.com/pricing.html or email [e-mail] for
**   information about Qt Commercial License Agreements.
** See http://www.trolltech.com/qpl/ for QPL licensing information.
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**********************************************************************/

#include "qlcdnumber.h"
#ifndef QT_NO_LCDNUMBER
#include "qbitarray.h"
#include "qpainter.h"


// NOT REVISED
/*!
  \class QLCDNumber qlcdnumber.h

  \brief The QLCDNumber widget displays a number with LCD-like digits.

  \ingroup basic

  It can display a number in just about any size, in decimal,
  hexadecimal, octal or binary notation, and is easy to connect to
  data sources via the display() slot, which is overloaded to take any
  of five argument types.

  There are also slots to change the \link setMode() notation mode
  \endlink and \link setSmallDecimalPoint() decimal point mode. \endlink

  QLCDNumber emits the overflow() signal when it is asked to display
  something beyond its range.  The range is set by setNumDigits() (but
  setSmallDecimalPoint() influences it too).

  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.

  It is not possible to retrieve the contents of a QLCDNumber object.
  If you need to, we recommend that you connect the signals which feed
  the display() slot to another slot as well and store the value
  there.

  Incidentally, QLCDNumber is the very oldest part of Qt, tracing back
  to a BASIC program on the <a
  href="http://www.nvg.ntnu.no/sinclair/spectrum.htm">Sinclair
  Spectrum</a>.

  <img src=qlcdnum-m.png> <img src=qlcdnum-w.png>

  \sa QLabel, QFrame
*/

/*! \enum QLCDNumber::Mode

  This type determines how numbers are shown. The possible values are:

  <ul>
  <li>\c Hex - Hexadecimal
  <li>\c Dec - Decimal
  <li>\c Oct - Octal
  <li>\c Bin - Binary
  </ul>
 */

/*! \enum QLCDNumber::SegmentStyle

  This type determines the visual appearance of the QLCDNumber
  widget. The possible values are:

  <ul>
  <li>\c Outline gives raised segments filled with the background brush.
  <li>\c Filled gives raised segments filled with the foreground brush.
  <li>\c Flat gives flat segments filled with the foreground brush.
  </ul>
 */



/*!
  \fn void QLCDNumber::overflow()

  This signal is emitted whenever the QLCDNumber is asked to display a
  too large number or a too long string.

  It is never emitted by setNumDigits().
*/


static QString int2string( int num, int base, int ndigits, bool *oflow )
{
    QString s;
    bool negative;
    if ( num < 0 ) {
	negative = TRUE;
	num	 = -num;
    } else {
	negative = FALSE;
    }
    switch( base ) {
	case QLCDNumber::HEX:
	    s.sprintf( "%*x", ndigits, num );
	    break;
	case QLCDNumber::DEC:
	    s.sprintf( "%*i", ndigits, num );
	    break;
	case QLCDNumber::OCT:
	    s.sprintf( "%*o", ndigits, num );
	    break;
	case QLCDNumber::BIN:
	    {
		char buf[42];
		char *p = &buf[41];
		uint n = num;
		int len = 0;
		*p = '\0';
		do {
		    *--p = (char)((n&1)+'0');
		    n >>= 1;
		    len++;
		} while ( n != 0 );
		len = ndigits - len;
		if ( len > 0 )
		s.fill( ' ', len );
		s += QString::fromLatin1(p);
	    }
	    break;
    }
    if ( negative ) {
	for ( int i=0; i<(int)s.length(); i++ ) {
	    if ( s[i] != ' ' ) {
		if ( i != 0 ) {
		    s[i-1] = '-';
		} else {
		    s.insert( 0, '-' );
		}
		break;
	    }
	}
    }
    if ( oflow )
	*oflow = (int)s.length() > ndigits;
    return s;
}


static QString double2string( double num, int base, int ndigits, bool *oflow )
{
    QString s;
    if ( base != QLCDNumber::DEC ) {
	bool of = num >= 2147483648.0 || num < -2147483648.0;
	if ( of ) {				// oops, integer overflow
	    if ( oflow )
		*oflow = TRUE;
	    return s;
	}
	s = int2string( (int)num, base, ndigits, 0 );
    } else {					// decimal base
	int nd = ndigits;
	do {
	    s.sprintf( "%*.*g", ndigits, nd, num );
	    int i = s.find('e');
	    if ( i > 0 && s[i+1]=='+' ) {
		s[i] = ' ';
		s[i+1] = 'e';
	    }
	} while (nd-- && (int)s.length() > ndigits);
    }
    if ( oflow )
	*oflow = (int)s.length() > ndigits;
    return s;
}


static const char *getSegments( char ch )		// gets list of segments for ch
{
    static const char segments[30][8] =
       { { 0, 1, 2, 4, 5, 6,99, 0},		// 0	0 / O
	 { 2, 5,99, 0, 0, 0, 0, 0},		// 1	1
	 { 0, 2, 3, 4, 6,99, 0, 0},		// 2	2
	 { 0, 2, 3, 5, 6,99, 0, 0},		// 3	3
	 { 1, 2, 3, 5,99, 0, 0, 0},		// 4	4
	 { 0, 1, 3, 5, 6,99, 0, 0},		// 5	5 / S
	 { 0, 1, 3, 4, 5, 6,99, 0},		// 6	6
	 { 0, 2, 5,99, 0, 0, 0, 0},		// 7	7
	 { 0, 1, 2, 3, 4, 5, 6,99},		// 8	8
	 { 0, 1, 2, 3, 5, 6,99, 0},		// 9	9 / g
	 { 3,99, 0, 0, 0, 0, 0, 0},		// 10	-
	 { 7,99, 0, 0, 0, 0, 0, 0},		// 11	.
	 { 0, 1, 2, 3, 4, 5,99, 0},		// 12	A
	 { 1, 3, 4, 5, 6,99, 0, 0},		// 13	B
	 { 0, 1, 4, 6,99, 0, 0, 0},		// 14	C
	 { 2, 3, 4, 5, 6,99, 0, 0},		// 15	D
	 { 0, 1, 3, 4, 6,99, 0, 0},		// 16	E
	 { 0, 1, 3, 4,99, 0, 0, 0},		// 17	F
	 { 1, 3, 4, 5,99, 0, 0, 0},		// 18	h
	 { 1, 2, 3, 4, 5,99, 0, 0},		// 19	H
	 { 1, 4, 6,99, 0, 0, 0, 0},		// 20	L
	 { 3, 4, 5, 6,99, 0, 0, 0},		// 21	o
	 { 0, 1, 2, 3, 4,99, 0, 0},		// 22	P
	 { 3, 4,99, 0, 0, 0, 0, 0},		// 23	r
	 { 4, 5, 6,99, 0, 0, 0, 0},		// 24	u
	 { 1, 2, 4, 5, 6,99, 0, 0},		// 25	U
	 { 1, 2, 3, 5, 6,99, 0, 0},		// 26	Y
	 { 8, 9,99, 0, 0, 0, 0, 0},		// 27	:
	 { 0, 1, 2, 3,99, 0, 0, 0},		// 28	'
	 {99, 0, 0, 0, 0, 0, 0, 0} };		// 29	empty

    if (ch >= '0' && ch <= '9')
	return segments[ch - '0'];
    if (ch >= 'A' && ch <= 'F')
	return segments[ch - 'A' + 12];
    if (ch >= 'a' && ch <= 'f')
	return segments[ch - 'a' + 12];

    int n;
    switch ( ch ) {
	case '-':
	    n = 10;  break;
	case 'O':
	    n = 0;   break;
	case 'g':
	    n = 9;   break;
	case '.':
	    n = 11;  break;
	case 'h':
	    n = 18;  break;
	case 'H':
	    n = 19;  break;
	case 'l':
	case 'L':
	    n = 20;  break;
	case 'o':
	    n = 21;  break;
	case 'p':
	case 'P':
	    n = 22;  break;
	case 'r':
	case 'R':
	    n = 23;  break;
	case 's':
	case 'S':
	    n = 5;   break;
	case 'u':
	    n = 24;  break;
	case 'U':
	    n = 25;  break;
	case 'y':
	case 'Y':
	    n = 26;  break;
	case ':':
	    n = 27;  break;
	case '\'':
	    n = 28;  break;
	default:
	    n = 29;  break;
    }
    return segments[n];
}


/*!
  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 \c Outline.

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

  \sa setNumDigits(), setSmallDecimalPoint()
*/

QLCDNumber::QLCDNumber( QWidget *parent, const char *name )
	: QFrame( parent, name )
{
    ndigits = 5;
    init();
}


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

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

  \sa setNumDigits(), setSmallDecimalPoint()
*/

QLCDNumber::QLCDNumber( uint numDigits, QWidget *parent, const char *name )
	: QFrame( parent, name )
{
    ndigits = numDigits;
    init();
}

/*!
  \internal
*/

void QLCDNumber::init()
{
    setFrameStyle( QFrame::Box | QFrame::Raised );
    val	       = 0;
    base       = DEC;
    smallPoint = FALSE;
    setNumDigits( ndigits );
    setSegmentStyle( Outline );
    d = 0;
    setSizePolicy( QSizePolicy( QSizePolicy::Minimum, QSizePolicy::Minimum ) );
}

/*!
  Destructs the LCD number.
*/

QLCDNumber::~QLCDNumber()
{
}


/*!
  \fn int QLCDNumber::numDigits() const

  Returns the current number of digits.	 If smallDecimalPoint() is
  FALSE, the decimal point occupies one digit position.

  \sa setNumDigits(), smallDecimalPoint()
*/

/*!
  Sets the number of digits shown to \e numDigits, which is forced
  into the [0-99] range.

  If smallDecimalPoint() is TRUE, \e numDigits can be shown.  If it is
  FALSE, only \e numDigits-1 digits can be shown.

  \sa numDigits(), setMode(), setSmallDecimalPoint(), overflow()
*/

void QLCDNumber::setNumDigits( int numDigits )
{
    if ( numDigits > 99 ) {
#if defined(CHECK_RANGE)
	qWarning( "QLCDNumber::setNumDigits: (%s) Max 99 digits allowed",
		 name( "unnamed" ) );
#endif
	numDigits = 99;
    }
    if ( digitStr.isNull() ) {			// from constructor
	ndigits = numDigits;
	digitStr.fill( ' ', ndigits );
	points.fill( 0, ndigits );
	digitStr[ndigits - 1] = '0';		// "0" is the default number
    } else {
	bool doDisplay = ndigits == 0;
	if ( numDigits == ndigits )		// no change
	    return;
	register int i;
	int dif;
	if ( numDigits > ndigits ) {		// expand
	    dif = numDigits - ndigits;
	    QString buf;
	    buf.fill( ' ', dif );
	    digitStr.insert( 0, buf );
	    points.resize( numDigits );
	    for ( i=numDigits-1; i>=dif; i-- )
		points.setBit( i, points.testBit(i-dif) );
	    for ( i=0; i<dif; i++ )
		points.clearBit( i );
	} else {					// shrink
	    dif = ndigits - numDigits;
	    digitStr = digitStr.right( numDigits );
	    QBitArray tmpPoints = points.copy();
	    points.resize( numDigits );
	    for ( i=0; i<(int)numDigits; i++ )
		points.setBit( i, tmpPoints.testBit(i+dif) );
	}
	ndigits = numDigits;
	if ( doDisplay )
	    display( value() );
	update();
    }
}


/*!
  Returns TRUE if \e num is too big to be displayed in its entirety,
  FALSE otherwise.
  \sa display(), numDigits(), smallDecimalPoint()
*/

bool QLCDNumber::checkOverflow( int num ) const
{
    bool of;
    int2string( num, base, ndigits, &of );
    return of;
}


/*!
  Returns TRUE if \e num is too big to be displayed in its entirety,
  FALSE otherwise.
  \sa display(), numDigits(), smallDecimalPoint()
*/

bool QLCDNumber::checkOverflow( double num ) const
{
    bool of;
    double2string( num, base, ndigits, &of );
    return of;
}


/*!
  Returns the current display mode, which is one of \c BIN, \c OCT, \c DEC
  and \c HEX.
  \sa setMode(), smallDecimalPoint()
*/

QLCDNumber::Mode QLCDNumber::mode() const
{
    return (QLCDNumber::Mode) base;
}


/*!
  Returns the last value set by one of the display() slots.

  If display(QString ) was the last called, 0 is returned.

  \sa intValue(), display()
*/

double QLCDNumber::value() const
{
    return val;
}

/*!
  Returns the last value set by one of the display() slots rounded to the
  nearest integer.

  If display(QString ) was the last called, 0 is returned.

  \sa value(), display()
*/

int QLCDNumber::intValue() const
{
    return (int)(val < 0 ? val - 0.5 : val + 0.5);
}


/*!
  Sets the contents of the display to \e num.
  \sa setMode(), smallDecimalPoint()
*/

void QLCDNumber::display( int num )
{
    val = (double)num;
    bool of;
    QString s = int2string( num, base, ndigits, &of );
    if ( of )
	emit overflow();
    else
	internalSetString( s );
}


/*!
  \overload void QLCDNumber::display( double num )
*/

void QLCDNumber::display( double num )
{
    val = num;
    bool of;
    QString s = double2string( num, base, ndigits, &of );
    if ( of )
	emit overflow();
    else
	internalSetString( s );
}


/*!
  \overload void QLCDNumber::display( const QString& s )

  This version of the function disregards mode() and smallDecimalPoint().

  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.
*/

void QLCDNumber::display( const QString &s )
{
    val = 0;
    internalSetString( s );
}

/*!
  Calls setMode( HEX ). Provided for convenience (e.g. for connecting
  buttons to this).

  \sa setMode(), setDecMode(), setOctMode(), setBinMode(), mode()
*/

void QLCDNumber::setHexMode()
{
    setMode( HEX );
}


/*!
  Calls setMode( DEC ). Provided for convenience (e.g. for connecting
  buttons to this).

  \sa setMode(), setHexMode(), setOctMode(), setBinMode(), mode()
*/

void QLCDNumber::setDecMode()
{
    setMode( DEC );
}


/*!
  Calls setMode( OCT ). Provided for convenience (e.g. for connecting
  buttons to this).

  \sa setMode(), setHexMode(), setDecMode(), setBinMode(), mode()
*/

void QLCDNumber::setOctMode()
{
    setMode( OCT );
}


/*!
  Calls setMode( BIN ). Provided for convenience (e.g. for connecting
  buttons to this).

  \sa setMode(), setHexMode(), setDecMode(), setOctMode(), mode()
*/

void QLCDNumber::setBinMode()
{
    setMode( BIN );
}