qstyleditemdelegate.cpp

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#include "qstyleditemdelegate.h"

#ifndef QT_NO_ITEMVIEWS
#include <qabstractitemmodel.h>
#include <qapplication.h>
#include <qbrush.h>
#include <qlineedit.h>
#include <qtextedit.h>
#include <qplaintextedit.h>
#include <qpainter.h>
#include <qpalette.h>
#include <qpoint.h>
#include <qrect.h>
#include <qsize.h>
#include <qstyle.h>
#include <qdatetime.h>
#include <qstyleoption.h>
#include <qevent.h>
#include <qpixmap.h>
#include <qbitmap.h>
#include <qpixmapcache.h>
#include <qitemeditorfactory.h>
#include <private/qitemeditorfactory_p.h>
#include <qmetaobject.h>
#include <qtextlayout.h>
#include <private/qobject_p.h>
#include <private/qdnd_p.h>
#include <private/qtextengine_p.h>
#include <private/qlayoutengine_p.h>
#include <qdebug.h>
#include <qlocale.h>
#include <qdialog.h>
#include <qtableview.h>

#include <limits.h>

QT_BEGIN_NAMESPACE

class QStyledItemDelegatePrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QStyledItemDelegate)

public:
    QStyledItemDelegatePrivate() : factory(0) { }

    static const QWidget *widget(const QStyleOptionViewItem &option)
    {
        if (const QStyleOptionViewItemV3 *v3 = qstyleoption_cast<const QStyleOptionViewItemV3 *>(&option))
            return v3->widget;
        return 0;
    }

    const QItemEditorFactory *editorFactory() const
    {
        return factory ? factory : QItemEditorFactory::defaultFactory();
    }

    void _q_commitDataAndCloseEditor(QWidget *editor)
    {
        Q_Q(QStyledItemDelegate);
        emit q->commitData(editor);
        emit q->closeEditor(editor, QAbstractItemDelegate::SubmitModelCache);
    }
    QItemEditorFactory *factory;
};

QStyledItemDelegate::QStyledItemDelegate(QObject *parent)
    : QAbstractItemDelegate(*new QStyledItemDelegatePrivate(), parent)
{
}

QStyledItemDelegate::~QStyledItemDelegate()
{
}

QString QStyledItemDelegate::displayText(const QVariant &value, const QLocale& locale) const
{
    QString text;
    switch (value.userType()) {
    case QMetaType::Float:
    case QVariant::Double:
        text = locale.toString(value.toReal());
        break;
    case QVariant::Int:
    case QVariant::LongLong:
        text = locale.toString(value.toLongLong());
        break;
    case QVariant::UInt:
    case QVariant::ULongLong:
        text = locale.toString(value.toULongLong());
        break;
    case QVariant::Date:
        text = locale.toString(value.toDate(), QLocale::ShortFormat);
        break;
    case QVariant::Time:
        text = locale.toString(value.toTime(), QLocale::ShortFormat);
        break;
    case QVariant::DateTime:
        text = locale.toString(value.toDateTime().date(), QLocale::ShortFormat);
        text += QLatin1Char(' ');
        text += locale.toString(value.toDateTime().time(), QLocale::ShortFormat);
        break;
    default:
        // convert new lines into line separators
        text = value.toString();
        for (int i = 0; i < text.count(); ++i) {
            if (text.at(i) == QLatin1Char('\n'))
                text[i] = QChar::LineSeparator;
        }
        break;
    }
    return text;
}

void QStyledItemDelegate::initStyleOption(QStyleOptionViewItem *option,
                                         const QModelIndex &index) const
{
    QVariant value = index.data(Qt::FontRole);
    if (value.isValid() && !value.isNull()) {
        option->font = qvariant_cast<QFont>(value).resolve(option->font);
        option->fontMetrics = QFontMetrics(option->font);
    }

    value = index.data(Qt::TextAlignmentRole);
    if (value.isValid() && !value.isNull())
        option->displayAlignment = Qt::Alignment(value.toInt());

    value = index.data(Qt::ForegroundRole);
    if (value.canConvert<QBrush>())
        option->palette.setBrush(QPalette::Text, qvariant_cast<QBrush>(value));

    if (QStyleOptionViewItemV4 *v4 = qstyleoption_cast<QStyleOptionViewItemV4 *>(option)) {
        v4->index = index;
        QVariant value = index.data(Qt::CheckStateRole);
        if (value.isValid() && !value.isNull()) {
            v4->features |= QStyleOptionViewItemV2::HasCheckIndicator;
            v4->checkState = static_cast<Qt::CheckState>(value.toInt());
        }

        value = index.data(Qt::DecorationRole);
        if (value.isValid() && !value.isNull()) {
            v4->features |= QStyleOptionViewItemV2::HasDecoration;
            switch (value.type()) {
            case QVariant::Icon: {
                v4->icon = qvariant_cast<QIcon>(value);
                QIcon::Mode mode;
                if (!(option->state & QStyle::State_Enabled))
                    mode = QIcon::Disabled;
                else if (option->state & QStyle::State_Selected)
                    mode = QIcon::Selected;
                else
                    mode = QIcon::Normal;
                QIcon::State state = option->state & QStyle::State_Open ? QIcon::On : QIcon::Off;
                v4->decorationSize = v4->icon.actualSize(option->decorationSize, mode, state);
                break;
            }
            case QVariant::Color: {
                QPixmap pixmap(option->decorationSize);
                pixmap.fill(qvariant_cast<QColor>(value));
                v4->icon = QIcon(pixmap);
                break;
            }
            case QVariant::Image: {
                QImage image = qvariant_cast<QImage>(value);
                v4->icon = QIcon(QPixmap::fromImage(image));
                v4->decorationSize = image.size();
                break;
            }
            case QVariant::Pixmap: {
                QPixmap pixmap = qvariant_cast<QPixmap>(value);
                v4->icon = QIcon(pixmap);
                v4->decorationSize = pixmap.size();
                break;
            }
            default:
                break;
            }
        }

        value = index.data(Qt::DisplayRole);
        if (value.isValid() && !value.isNull()) {
            v4->features |= QStyleOptionViewItemV2::HasDisplay;
            v4->text = displayText(value, v4->locale);
        }

        v4->backgroundBrush = qvariant_cast<QBrush>(index.data(Qt::BackgroundRole));
    }
}

void QStyledItemDelegate::paint(QPainter *painter,
        const QStyleOptionViewItem &option, const QModelIndex &index) const
{
    Q_ASSERT(index.isValid());

    QStyleOptionViewItemV4 opt = option;
    initStyleOption(&opt, index);

    const QWidget *widget = QStyledItemDelegatePrivate::widget(option);
    QStyle *style = widget ? widget->style() : QApplication::style();
    style->drawControl(QStyle::CE_ItemViewItem, &opt, painter, widget);
}

QSize QStyledItemDelegate::sizeHint(const QStyleOptionViewItem &option,
                                   const QModelIndex &index) const
{
    QVariant value = index.data(Qt::SizeHintRole);
    if (value.isValid())
        return qvariant_cast<QSize>(value);

    QStyleOptionViewItemV4 opt = option;
    initStyleOption(&opt, index);
    const QWidget *widget = QStyledItemDelegatePrivate::widget(option);
    QStyle *style = widget ? widget->style() : QApplication::style();
    return style->sizeFromContents(QStyle::CT_ItemViewItem, &opt, QSize(), widget);
}

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

void QStyledItemDelegate::setEditorData(QWidget *editor, const QModelIndex &index) const
{
#ifdef QT_NO_PROPERTIES
    Q_UNUSED(editor);
    Q_UNUSED(index);
#else
    Q_D(const QStyledItemDelegate);
    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";
    }

    // ### Qt 5: give QComboBox a USER property
    if (n.isEmpty() && editor->inherits("QComboBox"))
        n = d->editorFactory()->valuePropertyName(static_cast<QVariant::Type>(v.userType()));
    if (!n.isEmpty()) {
        if (!v.isValid())
            v = QVariant(editor->property(n).userType(), (const void *)0);
        editor->setProperty(n, v);
    }
#endif
}

void QStyledItemDelegate::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 QStyledItemDelegate);
    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
}

void QStyledItemDelegate::updateEditorGeometry(QWidget *editor,
                                         const QStyleOptionViewItem &option,
                                         const QModelIndex &index) const
{
    if (!editor)
        return;
    Q_ASSERT(index.isValid());
    const QWidget *widget = QStyledItemDelegatePrivate::widget(option);

    QStyleOptionViewItemV4 opt = option;
    initStyleOption(&opt, index);
    // let the editor take up all available space
    //if the editor is not a QLineEdit
    //or it is in a QTableView
#if !defined(QT_NO_TABLEVIEW) && !defined(QT_NO_LINEEDIT)
    if (qobject_cast<QExpandingLineEdit*>(editor) && !qobject_cast<const QTableView*>(widget))
        opt.showDecorationSelected = editor->style()->styleHint(QStyle::SH_ItemView_ShowDecorationSelected, 0, editor);
    else
#endif
        opt.showDecorationSelected = true;

    QStyle *style = widget ? widget->style() : QApplication::style();
    QRect geom = style->subElementRect(QStyle::SE_ItemViewItemText, &opt, widget);
    if ( editor->layoutDirection() == Qt::RightToLeft) {
        const int delta = qSmartMinSize(editor).width() - geom.width();
        if (delta > 0) {
            //we need to widen the geometry
            geom.adjust(-delta, 0, 0, 0);
        }
    }

    editor->setGeometry(geom);
}

QItemEditorFactory *QStyledItemDelegate::itemEditorFactory() const
{
    Q_D(const QStyledItemDelegate);
    return d->factory;
}

void QStyledItemDelegate::setItemEditorFactory(QItemEditorFactory *factory)
{
    Q_D(QStyledItemDelegate);
    d->factory = factory;
}


bool QStyledItemDelegate::eventFilter(QObject *object, QEvent *event)
{
    QWidget *editor = qobject_cast<QWidget*>(object);
    if (!editor)
        return false;
    if (event->type() == QEvent::KeyPress) {
        switch (static_cast<QKeyEvent *>(event)->key()) {
        case Qt::Key_Tab:
            emit commitData(editor);
            emit closeEditor(editor, QAbstractItemDelegate::EditNextItem);
            return true;
        case Qt::Key_Backtab:
            emit commitData(editor);
            emit closeEditor(editor, QAbstractItemDelegate::EditPreviousItem);
            return true;
        case Qt::Key_Enter:
        case Qt::Key_Return:
#ifndef QT_NO_TEXTEDIT
            if (qobject_cast<QTextEdit *>(editor) || qobject_cast<QPlainTextEdit *>(editor))
                return false; // don't filter enter key events for QTextEdit
            // We want the editor to be able to process the key press
            // before committing the data (e.g. so it can do
            // validation/fixup of the input).
#endif // QT_NO_TEXTEDIT
#ifndef QT_NO_LINEEDIT
            if (QLineEdit *e = qobject_cast<QLineEdit*>(editor))
                if (!e->hasAcceptableInput())
                    return false;
#endif // QT_NO_LINEEDIT
            QMetaObject::invokeMethod(this, "_q_commitDataAndCloseEditor",
                                      Qt::QueuedConnection, Q_ARG(QWidget*, editor));
            return false;
        case Qt::Key_Escape:
            // don't commit data
            emit closeEditor(editor, QAbstractItemDelegate::RevertModelCache);
            break;
        default:
            return false;
        }
        if (editor->parentWidget())
            editor->parentWidget()->setFocus();
        return true;
    } else if (event->type() == QEvent::FocusOut || (event->type() == QEvent::Hide && editor->isWindow())) {
        //the Hide event will take care of he editors that are in fact complete dialogs
        if (!editor->isActiveWindow() || (QApplication::focusWidget() != editor)) {
            QWidget *w = QApplication::focusWidget();
            while (w) { // don't worry about focus changes internally in the editor
                if (w == editor)
                    return false;
                w = w->parentWidget();
            }
#ifndef QT_NO_DRAGANDDROP
            // The window may lose focus during an drag operation.
            // i.e when dragging involves the taskbar on Windows.
            if (QDragManager::self() && QDragManager::self()->object != 0)
                return false;
#endif

            emit commitData(editor);
            emit closeEditor(editor, NoHint);
        }
    } else if (event->type() == QEvent::ShortcutOverride) {
        if (static_cast<QKeyEvent*>(event)->key() == Qt::Key_Escape) {
            event->accept();
            return true;
        }
    }
    return false;
}

bool QStyledItemDelegate::editorEvent(QEvent *event,
                                QAbstractItemModel *model,
                                const QStyleOptionViewItem &option,
                                const QModelIndex &index)
{
    Q_ASSERT(event);
    Q_ASSERT(model);

    // make sure that the item is checkable
    Qt::ItemFlags flags = model->flags(index);
    if (!(flags & Qt::ItemIsUserCheckable) || !(option.state & QStyle::State_Enabled)
        || !(flags & Qt::ItemIsEnabled))
        return false;

    // make sure that we have a check state
    QVariant value = index.data(Qt::CheckStateRole);
    if (!value.isValid())
        return false;

    const QWidget *widget = QStyledItemDelegatePrivate::widget(option);
    QStyle *style = widget ? widget->style() : QApplication::style();

    // make sure that we have the right event type
    if ((event->type() == QEvent::MouseButtonRelease)
        || (event->type() == QEvent::MouseButtonDblClick)
        || (event->type() == QEvent::MouseButtonPress)) {
        QStyleOptionViewItemV4 viewOpt(option);
        initStyleOption(&viewOpt, index);
        QRect checkRect = style->subElementRect(QStyle::SE_ItemViewItemCheckIndicator, &viewOpt, widget);
        QMouseEvent *me = static_cast<QMouseEvent*>(event);
        if (me->button() != Qt::LeftButton || !checkRect.contains(me->pos()))
            return false;

        if ((event->type() == QEvent::MouseButtonPress)
            || (event->type() == QEvent::MouseButtonDblClick))
            return true;

    } else if (event->type() == QEvent::KeyPress) {
        if (static_cast<QKeyEvent*>(event)->key() != Qt::Key_Space
         && static_cast<QKeyEvent*>(event)->key() != Qt::Key_Select)
            return false;
    } else {
        return false;
    }

    Qt::CheckState state = (static_cast<Qt::CheckState>(value.toInt()) == Qt::Checked
                            ? Qt::Unchecked : Qt::Checked);
    return model->setData(index, state, Qt::CheckStateRole);
}

QT_END_NAMESPACE

#include "moc_qstyleditemdelegate.cpp"

#endif // QT_NO_ITEMVIEWS