qcombobox.cpp

奇趣公司比较新的qt/emd版本

/****************************************************************************
**
** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved.
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://trolltech.com/products/qt/licenses/licensing/opensource/
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
** or contact the sales department at [e-mail].
**
** In addition, as a special exception, Trolltech gives you certain
** additional rights. These rights are described in the Trolltech GPL
** Exception version 1.0, which can be found at
** http://www.trolltech.com/products/qt/gplexception/ and in the file
** GPL_EXCEPTION.txt in this package.
**
** In addition, as a special exception, Trolltech, as the sole copyright
** holder for Qt Designer, grants users of the Qt/Eclipse Integration
** plug-in the right for the Qt/Eclipse Integration to link to
** functionality provided by Qt Designer and its related libraries.
**
** Trolltech reserves all rights not expressly granted herein.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/

#include "qcombobox.h"

#ifndef QT_NO_COMBOBOX
#include <qstylepainter.h>
#include <qlineedit.h>
#include <qapplication.h>
#include <qdesktopwidget.h>
#include <qlistview.h>
#include <qitemdelegate.h>
#include <qstandarditemmodel.h>
#include <qmap.h>
#include <qmenu.h>
#include <qevent.h>
#include <qlayout.h>
#include <qscrollbar.h>
#ifndef QT_NO_IM
#include "qinputcontext.h"
#endif
#include <private/qcombobox_p.h>
#include <private/qabstractitemmodel_p.h>
#include <qdebug.h>

#ifdef Q_WS_X11
#include <private/qt_x11_p.h>
#endif

QComboBoxPrivate::QComboBoxPrivate()
    : QWidgetPrivate(),
      model(0),
      lineEdit(0),
      container(0),
      insertPolicy(QComboBox::InsertAtBottom),
      sizeAdjustPolicy(QComboBox::AdjustToContentsOnFirstShow),
      minimumContentsLength(0),
      shownOnce(false),
      autoCompletion(true),
      duplicatesEnabled(false),
      frame(true),
      maxVisibleItems(10),
      maxCount(INT_MAX),
      modelColumn(0),
      inserting(false),
      arrowState(QStyle::State_None),
      hoverControl(QStyle::SC_None),
      autoCompletionCaseSensitivity(Qt::CaseInsensitive),
      indexBeforeChange(-1)
#ifndef QT_NO_COMPLETER
      , completer(0)
#endif
{
}

QStyleOptionMenuItem QComboMenuDelegate::getStyleOption(const QStyleOptionViewItem &option,
                                                  const QModelIndex &index) const
{
    QStyleOptionMenuItem menuOption;
    menuOption.palette = QApplication::palette("QMenu");
    menuOption.state = QStyle::State_None;
    if (mCombo->window()->isActiveWindow())
        menuOption.state = QStyle::State_Active;
    if ((option.state & QStyle::State_Enabled) && (index.model()->flags(index) & Qt::ItemIsEnabled))
        menuOption.state |= QStyle::State_Enabled;
    else
        menuOption.palette.setCurrentColorGroup(QPalette::Disabled);
    if (option.state & QStyle::State_Selected)
        menuOption.state |= QStyle::State_Selected;
    menuOption.checkType = QStyleOptionMenuItem::NonExclusive;
    menuOption.checked = mCombo->currentIndex() == index.row();
    menuOption.menuItemType = QStyleOptionMenuItem::Normal;

    QVariant variant = index.model()->data(index, Qt::DecorationRole);
    switch (variant.type()) {
    case QVariant::Icon:
        menuOption.icon = qvariant_cast<QIcon>(variant);
        break;
    case QVariant::Color: {
        static QPixmap pixmap(option.decorationSize);
        pixmap.fill(qvariant_cast<QColor>(variant));
        menuOption.icon = pixmap;
        break; }
    default:
        menuOption.icon = qvariant_cast<QPixmap>(variant);
        break;
    }

    menuOption.text = index.model()->data(index, Qt::DisplayRole).toString()
                           .replace(QLatin1Char('&'), QLatin1String("&&"));
    menuOption.tabWidth = 0;
    menuOption.maxIconWidth =  option.decorationSize.width() + 4;
    menuOption.menuRect = option.rect;
    menuOption.rect = option.rect;
    extern QHash<QByteArray, QFont> *qt_app_fonts_hash();

    // Make sure fonts set on the combo box also overrides the font for the popup menu.
    if (mCombo->testAttribute(Qt::WA_SetFont))
        menuOption.font = mCombo->font();
    else
        menuOption.font = qt_app_fonts_hash()->value("QComboMenuItem", mCombo->font());

    menuOption.fontMetrics = QFontMetrics(menuOption.font);

    return menuOption;
}

#ifdef QT_KEYPAD_NAVIGATION
void QComboBoxPrivate::_q_completerActivated()
{
    Q_Q(QComboBox);
    if ( QApplication::keypadNavigationEnabled()
         && q->isEditable()
         && q->completer()
         && q->completer()->completionMode() == QCompleter::UnfilteredPopupCompletion ) {
        q->setEditFocus(false);
    }
}
#endif

void QComboBoxPrivate::updateArrow(QStyle::StateFlag state)
{
    Q_Q(QComboBox);
    if (arrowState == state)
        return;
    arrowState = state;
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    q->update(q->style()->subControlRect(QStyle::CC_ComboBox, &opt, QStyle::SC_ComboBoxArrow, q));
}

void QComboBoxPrivate::_q_modelReset()
{
    Q_Q(QComboBox);
    if (lineEdit) {
        lineEdit->setText(QString());
        updateLineEditGeometry();
    }
    q->update();
}

void QComboBoxPrivate::_q_modelDestroyed()
{
    model = QAbstractItemModelPrivate::staticEmptyModel();
}


//Windows and KDE allows menus to cover the taskbar, while GNOME and Mac don't
QRect QComboBoxPrivate::popupGeometry(int screen) const
{
#ifdef Q_WS_WIN
    return QApplication::desktop()->screenGeometry(screen);
#elif defined Q_WS_X11
    if (X11->desktopEnvironment == DE_KDE)
        return QApplication::desktop()->screenGeometry(screen);
    else
        return QApplication::desktop()->availableGeometry(screen);
#else
        return QApplication::desktop()->availableGeometry(screen);
#endif
}

bool QComboBoxPrivate::updateHoverControl(const QPoint &pos)
{

    Q_Q(QComboBox);
    QRect lastHoverRect = hoverRect;
    QStyle::SubControl lastHoverControl = hoverControl;
    bool doesHover = q->testAttribute(Qt::WA_Hover);
    if (lastHoverControl != newHoverControl(pos) && doesHover) {
        q->update(lastHoverRect);
        q->update(hoverRect);
        return true;
    }
    return !doesHover;
}

QStyle::SubControl QComboBoxPrivate::newHoverControl(const QPoint &pos)
{
    Q_Q(QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    opt.subControls = QStyle::SC_All;
    hoverControl = q->style()->hitTestComplexControl(QStyle::CC_ComboBox, &opt, pos, q);
    hoverRect = (hoverControl != QStyle::SC_None)
                   ? q->style()->subControlRect(QStyle::CC_ComboBox, &opt, hoverControl, q)
                   : QRect();
    return hoverControl;
}

/*
    Computes a size hint based on the maximum width
    for the items in the combobox.
*/
int QComboBoxPrivate::computeWidthHint() const
{
    Q_Q(const QComboBox);

    int width = 0;
    const int count = q->count();
    const int iconWidth = q->iconSize().width() + 4;
    const QFontMetrics &fontMetrics = q->fontMetrics();

    for (int i = 0; i < count; ++i) {
        const int textWidth = fontMetrics.width(q->itemText(i));
        if (q->itemIcon(i).isNull())
            width = (qMax(width, textWidth));
        else
            width = (qMax(width, textWidth + iconWidth));
    }

    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    QSize tmp(width, 0);
    tmp = q->style()->sizeFromContents(QStyle::CT_ComboBox, &opt, tmp, q);
    return tmp.width();
}

QSize QComboBoxPrivate::recomputeSizeHint(QSize &sh) const
{
    Q_Q(const QComboBox);
    if (!sh.isValid()) {
        bool hasIcon = sizeAdjustPolicy == QComboBox::AdjustToMinimumContentsLengthWithIcon ? true : false;
        int count = q->count();
        QSize iconSize = q->iconSize();
        const QFontMetrics &fm = q->fontMetrics();

        // text width
        if (&sh == &sizeHint || minimumContentsLength == 0) {
            switch (sizeAdjustPolicy) {
            case QComboBox::AdjustToContents:
            case QComboBox::AdjustToContentsOnFirstShow:
                if (count == 0) {
                    sh.rwidth() = 7 * fm.width(QLatin1Char('x'));
                } else {
                    for (int i = 0; i < count; ++i) {
                        if (!q->itemIcon(i).isNull()) {
                            hasIcon = true;
                            sh.setWidth(qMax(sh.width(), fm.width(q->itemText(i)) + iconSize.width() + 4));
                        } else {
                            sh.setWidth(qMax(sh.width(), fm.width(q->itemText(i))));
                        }
                    }
                }
                break;
            case QComboBox::AdjustToMinimumContentsLength:
                for (int i = 0; i < count && !hasIcon; ++i)
                    hasIcon = !q->itemIcon(i).isNull();
            default:
                ;
            }
        } else {
            for (int i = 0; i < count && !hasIcon; ++i)
                hasIcon = !q->itemIcon(i).isNull();
        }
        if (minimumContentsLength > 0)
            sh.setWidth(qMax(sh.width(), minimumContentsLength * fm.width(QLatin1Char('X')) + (hasIcon ? iconSize.width() + 4 : 0)));


        // height
        sh.setHeight(qMax(fm.lineSpacing(), 14) + 2);
        if (hasIcon) {
            sh.setHeight(qMax(sh.height(), iconSize.height() + 2));
        }

        // add style and strut values
        QStyleOptionComboBox opt;
        q->initStyleOption(&opt);
        sh = q->style()->sizeFromContents(QStyle::CT_ComboBox, &opt, sh, q);
    }
    return sh.expandedTo(QApplication::globalStrut());
}

void QComboBoxPrivate::adjustComboBoxSize()
{
    viewContainer()->adjustSizeTimer.start(20, container);
}

void QComboBoxPrivate::updateLayoutDirection()
{
    Q_Q(const QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    Qt::LayoutDirection dir = Qt::LayoutDirection(
        q->style()->styleHint(QStyle::SH_ComboBox_LayoutDirection, &opt, q));
    if (lineEdit)
        lineEdit->setLayoutDirection(dir);
    if (container)
        container->setLayoutDirection(dir);
}


void QComboBoxPrivateContainer::timerEvent(QTimerEvent *timerEvent)
{
    if (timerEvent->timerId() == adjustSizeTimer.timerId()) {
        adjustSizeTimer.stop();
        if (combo->sizeAdjustPolicy() == QComboBox::AdjustToContents) {
            combo->adjustSize();
            combo->update();
        }
    }
}

void QComboBoxPrivateContainer::resizeEvent(QResizeEvent *e)
{
    QStyleOptionComboBox opt = comboStyleOption();
    if (combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo)) {
        QStyleOption myOpt;
        myOpt.initFrom(this);
        QStyleHintReturnMask mask;
        if (combo->style()->styleHint(QStyle::SH_Menu_Mask, &myOpt, this, &mask)) {
            setMask(mask.region);
        }
    } else {
        clearMask();
    }
    QFrame::resizeEvent(e);
}

void QComboBoxPrivateContainer::leaveEvent(QEvent *)
{
// On Mac using the Mac style we want to clear the selection
// when the mouse moves outside the popup.
#ifdef Q_WS_MAC
    QStyleOptionComboBox opt = comboStyleOption();
    if (combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo))
        view->clearSelection();
#endif
}

QComboBoxPrivateContainer::QComboBoxPrivateContainer(QAbstractItemView *itemView, QComboBox *parent)
    : QFrame(parent, Qt::Popup), combo(parent), view(0), top(0), bottom(0)
{
    // we need the combobox and itemview
    Q_ASSERT(parent);
    Q_ASSERT(itemView);

    setAttribute(Qt::WA_WindowPropagation);

    // setup container
    blockMouseReleaseTimer.setSingleShot(true);

    // we need a vertical layout
    QBoxLayout *layout =  new QBoxLayout(QBoxLayout::TopToBottom, this);
    layout->setSpacing(0);
    layout->setMargin(0);

    // set item view
    setItemView(itemView);

    // add scroller arrows if style needs them
    QStyleOptionComboBox opt = comboStyleOption();
    const bool usePopup = combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo);
    if (usePopup) {
        top = new QComboBoxPrivateScroller(QAbstractSlider::SliderSingleStepSub, this);
        bottom = new QComboBoxPrivateScroller(QAbstractSlider::SliderSingleStepAdd, this);
        top->hide();
        bottom->hide();
    } else {
        setLineWidth(1);
    }

    setFrameStyle(combo->style()->styleHint(QStyle::SH_ComboBox_PopupFrameStyle, &opt, combo));

    if (top) {
        layout->insertWidget(0, top);
        connect(top, SIGNAL(doScroll(int)), this, SLOT(scrollItemView(int)));
    }
    if (bottom) {
        layout->addWidget(bottom);
        connect(bottom, SIGNAL(doScroll(int)), this, SLOT(scrollItemView(int)));
    }

    // Some styles (Mac) have a margin at the top and bottom of the popup.
    layout->insertSpacing(0, 0);
    layout->addSpacing(0);
    updateTopBottomMargin();
}

void QComboBoxPrivateContainer::scrollItemView(int action)
{
#ifndef QT_NO_SCROLLBAR
    if (view->verticalScrollBar())
        view->verticalScrollBar()->triggerAction(static_cast<QAbstractSlider::SliderAction>(action));
#endif
}

/*
    Hides or shows the scrollers when we emulate a popupmenu
*/