q3combobox.cpp

奇趣公司比较新的qt/emd版本

    for ( i = 0; i < count(); i++)
	if ( text( i ) == txt )
	    break;
    if ( i < count() )
	setCurrentItem( i );
    else if ( d->ed )
	d->ed->setText( txt );
    else
	changeItem( txt, currentItem() );
}


/*!
    Returns the text item at position \a index, or QString::null if
    the item is not a string.

    \sa currentText()
*/

QString Q3ComboBox::text( int index ) const
{
    if ( !checkIndex( "text", name(), count(), index ) )
	return QString::null;
    if ( d->usingListBox() ) {
	return d->listBox()->text( index );
    } else {
        QString retText = d->popup()->text(index);
        retText.replace(QLatin1String("&&"), QString(QLatin1Char('&')));
	return retText;
    }
}

/*!
    Returns the pixmap item at position \a index, or 0 if the item is
    not a pixmap.
*/

const QPixmap *Q3ComboBox::pixmap( int index ) const
{
    if ( !checkIndex( "pixmap", name(), count(), index ) )
	return 0;

    if (d->usingListBox()) {
        return d->listBox()->pixmap( index );
    } else {
        d->popupPixmaps[index] = d->popup()->pixmap(index);
        return d->popupPixmaps[index].isNull() ? 0 : &d->popupPixmaps[index];
    }
}

/*!
    Replaces the item at position \a index with the text \a t.
*/

void Q3ComboBox::changeItem( const QString &t, int index )
{
    if ( !checkIndex( "changeItem", name(), count(), index ) )
	return;
    if ( d->usingListBox() )
	d->listBox()->changeItem( t, index );
    else
	d->popup()->changeItem(index, t);
    if ( index == d->current ) {
	if ( d->ed ) {
	    d->ed->setText( text( d->current ) );
	    d->updateLinedGeometry();
	} else
	    update();
    }
}

/*!
    \overload

    Replaces the item at position \a index with the pixmap \a im,
    unless the combobox is editable.

    \sa insertItem()
*/

void Q3ComboBox::changeItem( const QPixmap &im, int index )
{
    if ( !checkIndex( "changeItem", name(), count(), index ) )
	return;
    if ( d->usingListBox() )
	d->listBox()->changeItem( im, index );
    else
	d->popup()->changeItem(index, im);
    if ( index == d->current )
	update();
}

/*!
    \overload

    Replaces the item at position \a index with the pixmap \a im and
    the text \a t.

    \sa insertItem()
*/

void Q3ComboBox::changeItem( const QPixmap &im, const QString &t, int index )
{
    if ( !checkIndex( "changeItem", name(), count(), index ) )
	return;
    if ( d->usingListBox() )
	d->listBox()->changeItem( im, t, index );
    else
	d->popup()->changeItem(index, im, t);
    if ( index == d->current )
	update();
}


int Q3ComboBox::currentItem() const
{
    return d->current;
}

void Q3ComboBox::setCurrentItem( int index )
{
    if ( index == d->current && !d->ed ) {
	return;
    }
    if ( !checkIndex( "setCurrentItem", name(), count(), index ) ) {
	return;
    }

    if ( d->usingListBox() && !( listBox()->item(index) && listBox()->item(index)->isSelectable() ) )
	return;

    QStyleOptionComboBox opt = d->getStyleOption();
    if(d->popup() && style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, this))
	d->popup()->setItemChecked(d->current, false);
    d->current = index;
    d->completeAt = 0;
    if ( d->ed ) {
	d->ed->setText( text( index ) );
	d->updateLinedGeometry();
    }
    // ### We want to keep ListBox's currentItem in sync, even if NOT popuped...
    if ( d->usingListBox() && d->listBox() ) {
	d->listBox()->setCurrentItem( index );
    } else {
	internalHighlight( index );
	// internalActivate( index ); ### this leads to weird behavior, as in 3.0.1
    }

    currentChanged();
}

/*!
    Returns true if auto-resize is enabled; otherwise returns false.

    \sa autoResize
*/

bool Q3ComboBox::autoResize() const
{
    return d->autoresize;
}

/*!
    If \a enable is true, enable auto-resize; disable it otherwise.

    \sa autoResize
*/

void Q3ComboBox::setAutoResize( bool enable )
{
    if ( (bool)d->autoresize != enable ) {
	d->autoresize = enable;
	if ( enable )
	    adjustSize();
    }
}


/*!
    \reimp

    This implementation caches the size hint to avoid resizing when
    the contents change dynamically. To invalidate the cached value
    call setFont().
*/
QSize Q3ComboBox::sizeHint() const
{
    if ( isVisible() && d->sizeHint.isValid() )
	return d->sizeHint;

    constPolish();
    int i, w;
    QFontMetrics fm = fontMetrics();

    int maxW = count() ? 18 : 7 * fm.width(QLatin1Char('x')) + 18;
    int maxH = QMAX( fm.lineSpacing(), 14 ) + 2;

    if ( !d->usingListBox() ) {
	w = d->popup()->sizeHint().width() - 2* d->popup()->frameWidth();
	if ( w > maxW )
	    maxW = w;
    } else {
	for( i = 0; i < count(); i++ ) {
	    w = d->listBox()->item( i )->width( d->listBox() );
	    if ( w > maxW )
		maxW = w;
	}
    }

    QStyleOptionComboBox opt = d->getStyleOption();
    d->sizeHint = (style()->sizeFromContents(QStyle::CT_ComboBox, &opt, QSize(maxW, maxH), this).
                   expandedTo(QApplication::globalStrut()));

    return d->sizeHint;
}


/*!
  \internal
  Receives activated signals from an internal popup list and emits
  the activated() signal.
*/

void Q3ComboBox::internalActivate( int index )
{
    QStyleOptionComboBox opt = d->getStyleOption();
    if ( d->current != index ) {
	if ( !d->usingListBox() || listBox()->item( index )->isSelectable() ) {
	    if (d->popup() && style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, this))
		d->popup()->setItemChecked(d->current, false);
	    d->current = index;
	    currentChanged();
	}
    }
    if ( d->usingListBox() )
	popDownListBox();
    else
	d->popup()->removeEventFilter( this );
    d->poppedUp = false;

    QString t( text( index ) );
    if ( d->ed ) {
	d->ed->setText( t );
	d->updateLinedGeometry();
    }
    emit activated( index );
    emit activated( t );
}

/*!
  \internal
  Receives highlighted signals from an internal popup list and emits
  the highlighted() signal.
*/

void Q3ComboBox::internalHighlight( int index )
{
    emit highlighted( index );
    QString t = text( index );
    if ( !t.isNull() )
	emit highlighted( t );
}

/*!
  \internal
  Receives timeouts after a click. Used to decide if a Motif style
  popup should stay up or not after a click.
*/
void Q3ComboBox::internalClickTimeout()
{
    d->shortClick = false;
}

/*!
    Sets the palette for both the combobox button and the combobox
    popup list to \a palette.
*/

void Q3ComboBox::setPalette( const QPalette &palette )
{
    QWidget::setPalette( palette );
    if ( d->listBox() )
	d->listBox()->setPalette( palette );
    if ( d->popup() )
	d->popup()->setPalette( palette );
}

/*!
    Sets the font for both the combobox button and the combobox popup
    list to \a font.
*/

void Q3ComboBox::setFont( const QFont &font )
{
    d->sizeHint = QSize();		// invalidate size hint
    QWidget::setFont( font );
    if ( d->usingListBox() )
	d->listBox()->setFont( font );
    else
	d->popup()->setFont( font );
    if (d->ed)
	d->ed->setFont( font );
    if ( d->autoresize )
	adjustSize();
}


/*!\reimp
*/

void Q3ComboBox::resizeEvent( QResizeEvent * e )
{
    if ( d->ed )
	d->updateLinedGeometry();
    if ( d->listBox() )
	d->listBox()->resize( width(), d->listBox()->height() );
    QWidget::resizeEvent( e );
}

/*!\reimp
*/

void Q3ComboBox::paintEvent( QPaintEvent * )
{
    QPainter p( this );
    const QColorGroup & g = colorGroup();
    p.setPen(g.text());

    if ( width() < 5 || height() < 5 ) {
	qDrawShadePanel( &p, rect(), g, false, 2,
			 &g.brush( QColorGroup::Button ) );
	return;
    }

    QStyleOptionComboBox opt = d->getStyleOption();
    bool reverse = QApplication::reverseLayout();
    if ( !d->usingListBox() &&
	 style()->styleHint(QStyle::SH_GUIStyle) == Qt::MotifStyle) {			// motif 1.x style
	int dist, buttonH, buttonW;
	dist     = 8;
	buttonH  = 7;
	buttonW  = 11;
	int xPos;
	int x0;
	int w = width() - dist - buttonW - 1;
	if ( reverse ) {
	    xPos = dist + 1;
	    x0 = xPos + 4;
	} else {
	    xPos = w;
	    x0 = 4;
	}
	qDrawShadePanel( &p, rect(), g, false,
			 style()->pixelMetric(QStyle::PM_DefaultFrameWidth, &opt, this),
			 &g.brush( QColorGroup::Button ) );
	qDrawShadePanel( &p, xPos, (height() - buttonH)/2,
			 buttonW, buttonH, g, false,
			 style()->pixelMetric(QStyle::PM_DefaultFrameWidth, &opt, this) );
	QRect clip( x0, 2, w - 2 - 4 - 5, height() - 4 );
	QString str = d->popup()->text( this->d->current );
	if ( !str.isNull() ) {
	    p.drawText( clip, Qt::AlignCenter | Qt::TextSingleLine, str );
	}

	QPixmap pix = d->popup()->pixmap( this->d->current );
	QIcon iconSet = d->popup()->iconSet( this->d->current );
	if (!pix.isNull() || !iconSet.isNull()) {
	    QPixmap pm = ( !pix.isNull() ? pix : iconSet.pixmap() );
	    p.setClipRect( clip );
	    p.drawPixmap( 4, (height()-pm.height())/2, pm );
	    p.setClipping( false );
	}

	if ( hasFocus() )
	    p.drawRect( xPos - 5, 4, width() - xPos + 1 , height() - 8 );
    } else if(!d->usingListBox()) {
	style()->drawComplexControl(QStyle::CC_ComboBox, &opt, &p, this);
        QRect re = style()->subControlRect(QStyle::CC_ComboBox, &opt,
                                           QStyle::SC_ComboBoxEditField, this);
	p.setClipRect( re );

	QString str = d->popup()->text( this->d->current );
	QPixmap pix = d->popup()->pixmap( this->d->current );
	if ( !str.isNull() ) {
	    p.save();
	    p.setFont(font());
	    QFontMetrics fm(font());
	    int x = re.x(), y = re.y() + fm.ascent();
            x += pix.width() + 5;
	    p.drawText( x, y, str );
	    p.restore();
	}
	if (!pix.isNull()) {
	    p.fillRect(re.x(), re.y(), pix.width() + 4, re.height(),
                        colorGroup().brush(QColorGroup::Base));
	    p.drawPixmap(re.x() + 2, re.y() + (re.height() - pix.height()) / 2, pix);
	}
    } else {
	style()->drawComplexControl(QStyle::CC_ComboBox, &opt, &p, this);
	QRect re = style()->subControlRect(QStyle::CC_ComboBox, &opt,
                                            QStyle::SC_ComboBoxEditField, this);
	p.setClipRect(re);

	if ( !d->ed ) {
	    Q3ListBoxItem * item = d->listBox()->item( d->current );
	    if ( item ) {
		int itemh = item->height( d->listBox() );
		p.translate( re.x(), re.y() + (re.height() - itemh)/2  );
		item->paint( &p );
	    }
	} else if ( d->listBox() && d->listBox()->item( d->current ) ) {
	    Q3ListBoxItem * item = d->listBox()->item( d->current );
	    const QPixmap *pix = item->pixmap();
	    if ( pix ) {
		p.fillRect( re.x(), re.y(), pix->width() + 4, re.height(),
			    colorGroup().brush( QColorGroup::Base ) );
		p.drawPixmap( re.x() + 2, re.y() +
			      ( re.height() - pix->height() ) / 2, *pix );
	    }
	}
	p.setClipping( false );
    }
}


/*!\reimp
*/

void Q3ComboBox::mousePressEvent( QMouseEvent *e )
{
    if ( e->button() != Qt::LeftButton )
	return;
    if ( d->discardNextMousePress ) {
	d->discardNextMousePress = false;
	return;
    }

    QStyleOptionComboBox opt = d->getStyleOption();
    QRect arrowRect = style()->subControlRect(QStyle::CC_ComboBox, &opt, QStyle::SC_ComboBoxArrow
                                               , this);

    // Correction for motif style, where arrow is smaller
    // and thus has a rect that doesn't fit the button.
    arrowRect.setHeight( QMAX(  height() - (2 * arrowRect.y()), arrowRect.height() ) );

    if ( count() && ( !editable() || arrowRect.contains( e->pos() ) ) ) {
	d->arrowPressed = false;

	if ( d->usingListBox() ) {
	    listBox()->blockSignals( true );
	    qApp->sendEvent( listBox(), e ); // trigger the listbox's autoscroll
	    listBox()->setCurrentItem(d->current);
	    listBox()->blockSignals( false );
	    popup();
	    if ( arrowRect.contains( e->pos() ) ) {
		d->arrowPressed = true;
		d->arrowDown    = true;
		repaint( false );
	    }
	} else {
	    popup();
	}
	QTimer::singleShot( 200, this, SLOT(internalClickTimeout()));
	d->shortClick = true;
    }
}

/*!\reimp
*/

void Q3ComboBox::mouseMoveEvent( QMouseEvent * )