qwt_counter.cpp

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/******************************************************************************
 * Qwt Widget Library
 * Copyright (C) 1997   Josef Wilgen
 * Copyright (C) 2002   Uwe Rathmann
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the Qwt License, Version 1.0
 *****************************************************************************/
 
#include "qwt_arrow_button.h"
#include "qwt_counter.h"
#include "qwt_painter.h"
#include "qwt_math.h"
 
#include <qlayout.h>
#include <qlineedit.h>
#include <qvalidator.h>
#include <qevent.h>
#include <qstyle.h>
 
class QwtCounter::PrivateData
{
  public:
    PrivateData()
        : minimum( 0.0 )
        , maximum( 0.0 )
        , singleStep( 1.0 )
        , isValid( false )
        , value( 0.0 )
        , wrapping( false )
    {
        increment[Button1] = 1;
        increment[Button2] = 10;
        increment[Button3] = 100;
    }
 
    QwtArrowButton* buttonDown[ButtonCnt];
    QwtArrowButton* buttonUp[ButtonCnt];
    QLineEdit* valueEdit;
 
    int increment[ButtonCnt];
    int numButtons;
 
    double minimum;
    double maximum;
    double singleStep;
 
    bool isValid;
    double value;
 
    bool wrapping;
};
 
QwtCounter::QwtCounter( QWidget* parent )
    : QWidget( parent )
{
    initCounter();
}
 
void QwtCounter::initCounter()
{
    m_data = new PrivateData;
 
    QHBoxLayout* layout = new QHBoxLayout( this );
    layout->setSpacing( 0 );
    layout->setContentsMargins( QMargins() );
 
    for ( int i = ButtonCnt - 1; i >= 0; i-- )
    {
        QwtArrowButton* btn =
            new QwtArrowButton( i + 1, Qt::DownArrow, this );
        btn->setFocusPolicy( Qt::NoFocus );
        layout->addWidget( btn );
 
        connect( btn, SIGNAL(released()), SLOT(btnReleased()) );
        connect( btn, SIGNAL(clicked()), SLOT(btnClicked()) );
 
        m_data->buttonDown[i] = btn;
    }
 
    m_data->valueEdit = new QLineEdit( this );
    m_data->valueEdit->setReadOnly( false );
    m_data->valueEdit->setValidator( new QDoubleValidator( m_data->valueEdit ) );
    layout->addWidget( m_data->valueEdit );
 
    connect( m_data->valueEdit, SIGNAL(editingFinished()), SLOT(textChanged()) );
 
    layout->setStretchFactor( m_data->valueEdit, 10 );
 
    for ( int i = 0; i < ButtonCnt; i++ )
    {
        QwtArrowButton* btn =
            new QwtArrowButton( i + 1, Qt::UpArrow, this );
        btn->setFocusPolicy( Qt::NoFocus );
        layout->addWidget( btn );
 
        connect( btn, SIGNAL(released()), SLOT(btnReleased()) );
        connect( btn, SIGNAL(clicked()), SLOT(btnClicked()) );
 
        m_data->buttonUp[i] = btn;
    }
 
    setNumButtons( 2 );
    setRange( 0.0, 1.0 );
    setSingleStep( 0.001 );
    setValue( 0.0 );
 
    setSizePolicy(
        QSizePolicy( QSizePolicy::Preferred, QSizePolicy::Fixed ) );
 
    setFocusProxy( m_data->valueEdit );
    setFocusPolicy( Qt::StrongFocus );
}
 
QwtCounter::~QwtCounter()
{
    delete m_data;
}
 
void QwtCounter::setValid( bool on )
{
    if ( on != m_data->isValid )
    {
        m_data->isValid = on;
 
        updateButtons();
 
        if ( m_data->isValid )
        {
            showNumber( value() );
            Q_EMIT valueChanged( value() );
        }
        else
        {
            m_data->valueEdit->setText( QString() );
        }
    }
}
 
bool QwtCounter::isValid() const
{
    return m_data->isValid;
}
 
void QwtCounter::setReadOnly( bool on )
{
    m_data->valueEdit->setReadOnly( on );
}
 
bool QwtCounter::isReadOnly() const
{
    return m_data->valueEdit->isReadOnly();
}
 
void QwtCounter::setValue( double value )
{
    const double vmin = qwtMinF( m_data->minimum, m_data->maximum );
    const double vmax = qwtMaxF( m_data->minimum, m_data->maximum );
 
    value = qBound( vmin, value, vmax );
 
    if ( !m_data->isValid || value != m_data->value )
    {
        m_data->isValid = true;
        m_data->value = value;
 
        showNumber( value );
        updateButtons();
 
        Q_EMIT valueChanged( value );
    }
}
 
double QwtCounter::value() const
{
    return m_data->value;
}
 
void QwtCounter::setRange( double min, double max )
{
    max = qwtMaxF( min, max );
 
    if ( m_data->maximum == max && m_data->minimum == min )
        return;
 
    m_data->minimum = min;
    m_data->maximum = max;
 
    setSingleStep( singleStep() );
 
    const double value = qBound( min, m_data->value, max );
 
    if ( value != m_data->value )
    {
        m_data->value = value;
 
        if ( m_data->isValid )
        {
            showNumber( value );
            Q_EMIT valueChanged( value );
        }
    }
 
    updateButtons();
}
 
void QwtCounter::setMinimum( double value )
{
    setRange( value, maximum() );
}
 
double QwtCounter::minimum() const
{
    return m_data->minimum;
}
 
void QwtCounter::setMaximum( double value )
{
    setRange( minimum(), value );
}
 
double QwtCounter::maximum() const
{
    return m_data->maximum;
}
 
void QwtCounter::setSingleStep( double stepSize )
{
    m_data->singleStep = qwtMaxF( stepSize, 0.0 );
}
 
double QwtCounter::singleStep() const
{
    return m_data->singleStep;
}
 
void QwtCounter::setWrapping( bool on )
{
    m_data->wrapping = on;
}
 
bool QwtCounter::wrapping() const
{
    return m_data->wrapping;
}
 
void QwtCounter::setNumButtons( int numButtons )
{
    if ( numButtons < 0 || numButtons > QwtCounter::ButtonCnt )
        return;
 
    for ( int i = 0; i < QwtCounter::ButtonCnt; i++ )
    {
        if ( i < numButtons )
        {
            m_data->buttonDown[i]->show();
            m_data->buttonUp[i]->show();
        }
        else
        {
            m_data->buttonDown[i]->hide();
            m_data->buttonUp[i]->hide();
        }
    }
 
    m_data->numButtons = numButtons;
}
 
int QwtCounter::numButtons() const
{
    return m_data->numButtons;
}
 
void QwtCounter::setIncSteps( QwtCounter::Button button, int numSteps )
{
    if ( button >= 0 && button < QwtCounter::ButtonCnt )
        m_data->increment[ button ] = numSteps;
}
 
int QwtCounter::incSteps( QwtCounter::Button button ) const
{
    if ( button >= 0 && button < QwtCounter::ButtonCnt )
        return m_data->increment[ button ];
 
    return 0;
}
 
 
void QwtCounter::setStepButton1( int nSteps )
{
    setIncSteps( QwtCounter::Button1, nSteps );
}
 
int QwtCounter::stepButton1() const
{
    return incSteps( QwtCounter::Button1 );
}
 
void QwtCounter::setStepButton2( int nSteps )
{
    setIncSteps( QwtCounter::Button2, nSteps );
}
 
int QwtCounter::stepButton2() const
{
    return incSteps( QwtCounter::Button2 );
}
 
void QwtCounter::setStepButton3( int nSteps )
{
    setIncSteps( QwtCounter::Button3, nSteps );
}
 
int QwtCounter::stepButton3() const
{
    return incSteps( QwtCounter::Button3 );
}
 
void QwtCounter::textChanged()
{
    bool converted = false;
 
    const double value = m_data->valueEdit->text().toDouble( &converted );
    if ( converted )
        setValue( value );
}
 
bool QwtCounter::event( QEvent* event )
{
    if ( event->type() == QEvent::PolishRequest )
    {
        const QFontMetrics fm = m_data->valueEdit->fontMetrics();
 
        const int w = QwtPainter::horizontalAdvance( fm, "W" ) + 8;
        for ( int i = 0; i < ButtonCnt; i++ )
        {
            m_data->buttonDown[i]->setMinimumWidth( w );
            m_data->buttonUp[i]->setMinimumWidth( w );
        }
    }
 
    return QWidget::event( event );
}
 
void QwtCounter::keyPressEvent ( QKeyEvent* event )
{
    bool accepted = true;
 
    switch ( event->key() )
    {
        case Qt::Key_Home:
        {
            if ( event->modifiers() & Qt::ControlModifier )
                setValue( minimum() );
            else
                accepted = false;
            break;
        }
        case Qt::Key_End:
        {
            if ( event->modifiers() & Qt::ControlModifier )
                setValue( maximum() );
            else
                accepted = false;
            break;
        }
        case Qt::Key_Up:
        {
            incrementValue( m_data->increment[0] );
            break;
        }
        case Qt::Key_Down:
        {
            incrementValue( -m_data->increment[0] );
            break;
        }
        case Qt::Key_PageUp:
        case Qt::Key_PageDown:
        {
            int increment = m_data->increment[0];
            if ( m_data->numButtons >= 2 )
                increment = m_data->increment[1];
            if ( m_data->numButtons >= 3 )
            {
                if ( event->modifiers() & Qt::ShiftModifier )
                    increment = m_data->increment[2];
            }
            if ( event->key() == Qt::Key_PageDown )
                increment = -increment;
            incrementValue( increment );
            break;
        }
        default:
        {
            accepted = false;
        }
    }
 
    if ( accepted )
    {
        event->accept();
        return;
    }
 
    QWidget::keyPressEvent ( event );
}
 
void QwtCounter::wheelEvent( QWheelEvent* event )
{
    event->accept();
 
    if ( m_data->numButtons <= 0 )
        return;
 
    int increment = m_data->increment[0];
    if ( m_data->numButtons >= 2 )
    {
        if ( event->modifiers() & Qt::ControlModifier )
            increment = m_data->increment[1];
    }
    if ( m_data->numButtons >= 3 )
    {
        if ( event->modifiers() & Qt::ShiftModifier )
            increment = m_data->increment[2];
    }
 
#if QT_VERSION < 0x050e00
    const QPoint wheelPos = event->pos();
    const int wheelDelta = event->delta();
#else
    const QPoint wheelPos = event->position().toPoint();
 
    const QPoint delta = event->angleDelta();
    const int wheelDelta = ( qAbs( delta.x() ) > qAbs( delta.y() ) )
        ? delta.x() : delta.y();
#endif
 
    for ( int i = 0; i < m_data->numButtons; i++ )
    {
        if ( m_data->buttonDown[i]->geometry().contains( wheelPos ) ||
            m_data->buttonUp[i]->geometry().contains( wheelPos ) )
        {
            increment = m_data->increment[i];
        }
    }
 
    incrementValue( wheelDelta / 120 * increment );
}
 
void QwtCounter::incrementValue( int numSteps )
{
    const double min = m_data->minimum;
    const double max = m_data->maximum;
    double stepSize = m_data->singleStep;
 
    if ( !m_data->isValid || min >= max || stepSize <= 0.0 )
        return;
 
 
#if 1
    stepSize = qwtMaxF( stepSize, 1.0e-10 * ( max - min ) );
#endif
 
    double value = m_data->value + numSteps * stepSize;
 
    if ( m_data->wrapping )
    {
        const double range = max - min;
 
        if ( value < min )
        {
            value += std::ceil( ( min - value ) / range ) * range;
        }
        else if ( value > max )
        {
            value -= std::ceil( ( value - max ) / range ) * range;
        }
    }
    else
    {
        value = qBound( min, value, max );
    }
 
    value = min + qRound( ( value - min ) / stepSize ) * stepSize;
 
    if ( stepSize > 1e-12 )
    {
        if ( qFuzzyCompare( value + 1.0, 1.0 ) )
        {
            // correct rounding error if value = 0
            value = 0.0;
        }
        else if ( qFuzzyCompare( value, max ) )
        {
            // correct rounding error at the border
            value = max;
        }
    }
 
    if ( value != m_data->value )
    {
        m_data->value = value;
        showNumber( m_data->value );
        updateButtons();
 
        Q_EMIT valueChanged( m_data->value );
    }
}
 
 
void QwtCounter::updateButtons()
{
    if ( m_data->isValid )
    {
        // 1. save enabled state of the smallest down- and up-button
        // 2. change enabled state on under- or over-flow
 
        for ( int i = 0; i < QwtCounter::ButtonCnt; i++ )
        {
            m_data->buttonDown[i]->setEnabled( value() > minimum() );
            m_data->buttonUp[i]->setEnabled( value() < maximum() );
        }
    }
    else
    {
        for ( int i = 0; i < QwtCounter::ButtonCnt; i++ )
        {
            m_data->buttonDown[i]->setEnabled( false );
            m_data->buttonUp[i]->setEnabled( false );
        }
    }
}
void QwtCounter::showNumber( double number )
{
    QString text;
    text.setNum( number );
 
    const int cursorPos = m_data->valueEdit->cursorPosition();
    m_data->valueEdit->setText( text );
    m_data->valueEdit->setCursorPosition( cursorPos );
}
 
void QwtCounter::btnClicked()
{
    for ( int i = 0; i < ButtonCnt; i++ )
    {
        if ( m_data->buttonUp[i] == sender() )
            incrementValue( m_data->increment[i] );
 
        if ( m_data->buttonDown[i] == sender() )
            incrementValue( -m_data->increment[i] );
    }
}
 
void QwtCounter::btnReleased()
{
    Q_EMIT buttonReleased( value() );
}
 
QSize QwtCounter::sizeHint() const
{
    QString tmp;
 
    int w = tmp.setNum( minimum() ).length();
    int w1 = tmp.setNum( maximum() ).length();
    if ( w1 > w )
        w = w1;
    w1 = tmp.setNum( minimum() + singleStep() ).length();
    if ( w1 > w )
        w = w1;
    w1 = tmp.setNum( maximum() - singleStep() ).length();
    if ( w1 > w )
        w = w1;
 
    tmp.fill( '9', w );
 
    w = QwtPainter::horizontalAdvance( m_data->valueEdit->fontMetrics(), tmp ) + 2;
 
    if ( m_data->valueEdit->hasFrame() )
        w += 2 * style()->pixelMetric( QStyle::PM_DefaultFrameWidth );
 
    // Now we replace default sizeHint contribution of m_data->valueEdit by
    // what we really need.
 
    w += QWidget::sizeHint().width() - m_data->valueEdit->sizeHint().width();
 
    const int h = qMin( QWidget::sizeHint().height(),
        m_data->valueEdit->minimumSizeHint().height() );
 
    return QSize( w, h );
}
 
#if QWT_MOC_INCLUDE
#include "moc_qwt_counter.cpp"
#endif