qitemdelegate.cpp

奇趣公司比较新的qt/emd版本

QString QItemDelegatePrivate::valueToText(const QVariant &value, const QStyleOptionViewItemV3 &option)
{
    QString text;
    switch (value.type()) {
        case QVariant::Double:
            text = option.locale.toString(value.toDouble());
            break;
        case QVariant::Int:
        case QVariant::LongLong:
            text = option.locale.toString(value.toLongLong());
            break;
        case QVariant::UInt:
        case QVariant::ULongLong:
            text = option.locale.toString(value.toULongLong());
            break;
        case QVariant::Date:
            text = option.locale.toString(value.toDate(), QLocale::ShortFormat);
            break;
        case QVariant::Time:
            text = option.locale.toString(value.toTime(), QLocale::ShortFormat);
            break;
        case QVariant::DateTime:
            text = option.locale.toString(value.toDateTime().date(), QLocale::ShortFormat);
            text += QLatin1Char(' ');
            text += option.locale.toString(value.toDateTime().time(), QLocale::ShortFormat);
            break;
        default:
            text = replaceNewLine(value.toString());
            break;
    }
    return text;
}

/*!
    Renders the delegate using the given \a painter and style \a option for
    the item specified by \a index.

    When reimplementing this function in a subclass, you should update the area
    held by the option's \l{QStyleOption::rect}{rect} variable, using the
    option's \l{QStyleOption::state}{state} variable to determine the state of
    the item to be displayed, and adjust the way it is painted accordingly.

    For example, a selected item may need to be displayed differently to
    unselected items, as shown in the following code:

    \quotefromfile itemviews/pixelator/pixeldelegate.cpp
    \skipto QStyle::State_Selected
    \printuntil else
    \dots

    After painting, you should ensure that the painter is returned to its
    the state it was supplied in when this function was called. For example,
    it may be useful to call QPainter::save() before painting and
    QPainter::restore() afterwards.

    \sa QStyle::State
*/
void QItemDelegate::paint(QPainter *painter,
                          const QStyleOptionViewItem &option,
                          const QModelIndex &index) const
{
    Q_D(const QItemDelegate);
    Q_ASSERT(index.isValid());

    QStyleOptionViewItemV3 opt = setOptions(index, option);

    const QStyleOptionViewItemV2 *v2 = qstyleoption_cast<const QStyleOptionViewItemV2 *>(&option);
    opt.features = v2 ? v2->features
                    : QStyleOptionViewItemV2::ViewItemFeatures(QStyleOptionViewItemV2::None);
    const QStyleOptionViewItemV3 *v3 = qstyleoption_cast<const QStyleOptionViewItemV3 *>(&option);
    opt.locale = v3 ? v3->locale : QLocale();
    opt.widget = v3 ? v3->widget : 0;

    // prepare
    painter->save();
    if (d->clipPainting)
        painter->setClipRect(opt.rect);

    // get the data and the rectangles

    QVariant value;

    QPixmap pixmap;
    QRect decorationRect;
    value = index.data(Qt::DecorationRole);
    if (value.isValid()) {
        // ### we need the pixmap to call the virtual function
        pixmap = decoration(opt, value);
        if (value.type() == QVariant::Icon) {
            d->tmp.icon = qvariant_cast<QIcon>(value);
            d->tmp.mode = d->iconMode(option.state);
            d->tmp.state = d->iconState(option.state);
            const QSize size = d->tmp.icon.actualSize(option.decorationSize,
                                                      d->tmp.mode, d->tmp.state);
            decorationRect = QRect(QPoint(0, 0), size);
        } else {
            d->tmp.icon = QIcon();
            decorationRect = QRect(QPoint(0, 0), pixmap.size());
        }
    } else {
        d->tmp.icon = QIcon();
        decorationRect = QRect();
    }

    QString text;
    QRect displayRect;
    value = index.data(Qt::DisplayRole);
    if (value.isValid()) {
        text = QItemDelegatePrivate::valueToText(value, opt);
        displayRect = textRectangle(painter, d->textLayoutBounds(opt), opt.font, text);
    }

    QRect checkRect;
    Qt::CheckState checkState = Qt::Unchecked;
    value = index.data(Qt::CheckStateRole);
    if (value.isValid()) {
        checkState = static_cast<Qt::CheckState>(value.toInt());
        checkRect = check(opt, opt.rect, value);
    }

    // do the layout

    doLayout(opt, &checkRect, &decorationRect, &displayRect, false);

    // draw the item

    drawBackground(painter, opt, index);
    drawCheck(painter, opt, checkRect, checkState);
    drawDecoration(painter, opt, decorationRect, pixmap);
    drawDisplay(painter, opt, displayRect, text);
    drawFocus(painter, opt, displayRect);

    // done
    painter->restore();
}

/*!
    Returns the size needed by the delegate to display the item
    specified by \a index, taking into account the style information
    provided by \a option.

    When reimplementing this function, note that in case of text
    items, QItemDelegate adds a margin (i.e. 2 *
    QStyle::PM_FocusFrameHMargin) to the length of the text.
*/

QSize QItemDelegate::sizeHint(const QStyleOptionViewItem &option,
                              const QModelIndex &index) const
{
    QVariant value = index.data(Qt::SizeHintRole);
    if (value.isValid())
        return qvariant_cast<QSize>(value);
    QRect decorationRect = rect(option, index, Qt::DecorationRole);
    QRect displayRect = rect(option, index, Qt::DisplayRole);
    QRect checkRect = rect(option, index, Qt::CheckStateRole);

    doLayout(option, &checkRect, &decorationRect, &displayRect, true);

    return (decorationRect|displayRect|checkRect).size();
}

/*!
    Returns the widget used to edit the item specified by \a index
    for editing. The \a parent widget and style \a option are used to
    control how the editor widget appears.

    \sa QAbstractItemDelegate::createEditor()
*/

QWidget *QItemDelegate::createEditor(QWidget *parent,
                                     const QStyleOptionViewItem &,
                                     const QModelIndex &index) const
{
    Q_D(const QItemDelegate);
    if (!index.isValid())
        return 0;
    QVariant::Type t = static_cast<QVariant::Type>(index.data(Qt::EditRole).userType());
    const QItemEditorFactory *factory = d->f;
    if (factory == 0)
        factory = QItemEditorFactory::defaultFactory();
    return factory->createEditor(t, parent);
}

/*!
    Sets the data to be displayed and edited by the \a editor for the
    item specified by \a index.

    The default implementation uses the editor's user property to set values.

    \sa QMetaProperty::isUser()
*/

void QItemDelegate::setEditorData(QWidget *editor, const QModelIndex &index) const
{
#ifdef QT_NO_PROPERTIES
    Q_UNUSED(editor);
    Q_UNUSED(index);
#else
    Q_D(const QItemDelegate);
    QVariant v = index.data(Qt::EditRole);
    QByteArray n = editor->metaObject()->userProperty().name();

    // ### Qt 5: remove
    // A work-around for missing "USER true" in qdatetimeedit.h for
    // QTimeEdit's time property and QDateEdit's date property.
    // It only triggers if the default user property "dateTime" is
    // reported for QTimeEdit and QDateEdit.
    if (n == "dateTime") {
        if (editor->inherits("QTimeEdit"))
            n = "time";
        else if (editor->inherits("QDateEdit"))
            n = "date";
    }

    if (n.isEmpty())
        n = d->editorFactory()->valuePropertyName(static_cast<QVariant::Type>(v.userType()));
    if (!n.isEmpty())
        editor->setProperty(n, v);
#endif
}

/*!
    Sets the data for the specified \a model and item \a index from that
    supplied by the \a editor.

    The default implementation uses the editor's user property to get values.

    \sa QMetaProperty::isUser()
*/

void QItemDelegate::setModelData(QWidget *editor,
                                 QAbstractItemModel *model,
                                 const QModelIndex &index) const
{
#ifdef QT_NO_PROPERTIES
    Q_UNUSED(model);
    Q_UNUSED(editor);
    Q_UNUSED(index);
#else
    Q_D(const QItemDelegate);
    Q_ASSERT(model);
    Q_ASSERT(editor);
    QByteArray n = editor->metaObject()->userProperty().name();
    if (n.isEmpty())
        n = d->editorFactory()->valuePropertyName(
            static_cast<QVariant::Type>(model->data(index, Qt::EditRole).userType()));
    if (!n.isEmpty())
        model->setData(index, editor->property(n), Qt::EditRole);
#endif
}

/*!
    Updates the \a editor for the item specified by \a index
    according to the style \a option given.
*/

void QItemDelegate::updateEditorGeometry(QWidget *editor,
                                         const QStyleOptionViewItem &option,
                                         const QModelIndex &index) const
{
    if (!editor)
        return;
    Q_ASSERT(index.isValid());
    QPixmap pixmap = decoration(option, index.data(Qt::DecorationRole));
    QString text = QItemDelegatePrivate::replaceNewLine(index.data(Qt::DisplayRole).toString());
    QRect pixmapRect = QRect(QPoint(0, 0), option.decorationSize).intersected(pixmap.rect());
    QRect textRect = textRectangle(0, option.rect, option.font, text);
    QRect checkRect = check(option, textRect, index.data(Qt::CheckStateRole));
    QStyleOptionViewItem opt = option;
    opt.showDecorationSelected = true; // let the editor take up all available space
    doLayout(opt, &checkRect, &pixmapRect, &textRect, false);
    editor->setGeometry(textRect);
}

/*!
  Returns the editor factory used by the item delegate.
  If no editor factory is set, the function will return null.

  \sa setItemEditorFactory()
*/
QItemEditorFactory *QItemDelegate::itemEditorFactory() const
{
    Q_D(const QItemDelegate);
    return d->f;
}

/*!
  Sets the editor factory to be used by the item delegate to be the \a factory
  specified. If no editor factory is set, the item delegate will use the
  default editor factory.

  \sa itemEditorFactory()
*/
void QItemDelegate::setItemEditorFactory(QItemEditorFactory *factory)
{
    Q_D(QItemDelegate);
    d->f = factory;
}

/*!
   Renders the item view \a text within the rectangle specified by \a rect
   using the given \a painter and style \a option.
*/

void QItemDelegate::drawDisplay(QPainter *painter, const QStyleOptionViewItem &option,
                                const QRect &rect, const QString &text) const
{
    Q_D(const QItemDelegate);

    if (text.isEmpty())
        return;

    QPen pen = painter->pen();
    QPalette::ColorGroup cg = option.state & QStyle::State_Enabled
                              ? QPalette::Normal : QPalette::Disabled;
    if (cg == QPalette::Normal && !(option.state & QStyle::State_Active))
        cg = QPalette::Inactive;
    if (option.state & QStyle::State_Selected) {
        painter->fillRect(rect, option.palette.brush(cg, QPalette::Highlight));
        painter->setPen(option.palette.color(cg, QPalette::HighlightedText));
    } else {