X-Git-Url: https://cloud.milkyroute.net/gitweb/dolphin.git/blobdiff_plain/fde79c09cb9ae5991d6b36c7c1d125628f2c7914..99c48acc8ea5e614e447a8f62d92c8d12e9cf58b:/src/kitemviews/private/kitemlistheaderwidget.cpp

diff --git a/src/kitemviews/private/kitemlistheaderwidget.cpp b/src/kitemviews/private/kitemlistheaderwidget.cpp
index 9a7e850a9..3dc82ad6b 100644
--- a/src/kitemviews/private/kitemlistheaderwidget.cpp
+++ b/src/kitemviews/private/kitemlistheaderwidget.cpp
@@ -1,5 +1,6 @@
 /*
  * SPDX-FileCopyrightText: 2011 Peter Penz <peter.penz19@gmail.com>
+ * SPDX-FileCopyrightText: 2022, 2024 Felix Ernst <felixernst@kde.org>
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
@@ -12,56 +13,80 @@
 #include <QPainter>
 #include <QStyleOptionHeader>
 
+namespace
+{
+/**
+ * @returns a list which has a reversed order of elements compared to @a list.
+ */
+QList<QByteArray> reversed(const QList<QByteArray> list)
+{
+    QList<QByteArray> reversedList;
+    for (auto i = list.rbegin(); i != list.rend(); i++) {
+        reversedList.emplaceBack(*i);
+    }
+    return reversedList;
+};
 
-KItemListHeaderWidget::KItemListHeaderWidget(QGraphicsWidget* parent) :
-    QGraphicsWidget(parent),
-    m_automaticColumnResizing(true),
-    m_model(nullptr),
-    m_offset(0),
-    m_columns(),
-    m_columnWidths(),
-    m_preferredColumnWidths(),
-    m_hoveredRoleIndex(-1),
-    m_pressedRoleIndex(-1),
-    m_roleOperation(NoRoleOperation),
-    m_pressedMousePos(),
-    m_movingRole()
+/**
+ * @returns the index of the column for the name/text of items. This depends on the layoutDirection() and column count of @a itemListHeaderWidget.
+ */
+int nameColumnIndex(const KItemListHeaderWidget *itemListHeaderWidget)
+{
+    if (itemListHeaderWidget->layoutDirection() == Qt::LeftToRight) {
+        return 0;
+    }
+    return itemListHeaderWidget->columns().count() - 1;
+};
+}
+
+KItemListHeaderWidget::KItemListHeaderWidget(QGraphicsWidget *parent)
+    : QGraphicsWidget(parent)
+    , m_automaticColumnResizing(true)
+    , m_model(nullptr)
+    , m_offset(0)
+    , m_leftPadding(0)
+    , m_rightPadding(0)
+    , m_columns()
+    , m_columnWidths()
+    , m_preferredColumnWidths()
+    , m_hoveredIndex(-1)
+    , m_pressedRoleIndex(-1)
+    , m_pressedMousePos()
+    , m_movingRole()
 {
     m_movingRole.x = 0;
     m_movingRole.xDec = 0;
     m_movingRole.index = -1;
 
     setAcceptHoverEvents(true);
+    // TODO update when font changes at runtime
+    setFont(QApplication::font("QHeaderView"));
 }
 
 KItemListHeaderWidget::~KItemListHeaderWidget()
 {
 }
 
-void KItemListHeaderWidget::setModel(KItemModelBase* model)
+void KItemListHeaderWidget::setModel(KItemModelBase *model)
 {
     if (m_model == model) {
         return;
     }
 
     if (m_model) {
-        disconnect(m_model, &KItemModelBase::sortRoleChanged,
-                   this, &KItemListHeaderWidget::slotSortRoleChanged);
-        disconnect(m_model, &KItemModelBase::sortOrderChanged,
-                   this, &KItemListHeaderWidget::slotSortOrderChanged);
+        disconnect(m_model, &KItemModelBase::sortRoleChanged, this, &KItemListHeaderWidget::slotSortRoleChanged);
+        disconnect(m_model, &KItemModelBase::sortOrderChanged, this, &KItemListHeaderWidget::slotSortOrderChanged);
     }
 
     m_model = model;
 
     if (m_model) {
-        connect(m_model, &KItemModelBase::sortRoleChanged,
-                this, &KItemListHeaderWidget::slotSortRoleChanged);
-        connect(m_model, &KItemModelBase::sortOrderChanged,
-                this, &KItemListHeaderWidget::slotSortOrderChanged);
+        connect(m_model, &KItemModelBase::sortRoleChanged, this, &KItemListHeaderWidget::slotSortRoleChanged);
+        connect(m_model, &KItemModelBase::sortOrderChanged, this, &KItemListHeaderWidget::slotSortOrderChanged);
     }
 }
 
-KItemModelBase* KItemListHeaderWidget::model() const
+KItemModelBase *KItemListHeaderWidget::model() const
 {
     return m_model;
 }
@@ -76,24 +101,24 @@ bool KItemListHeaderWidget::automaticColumnResizing() const
     return m_automaticColumnResizing;
 }
 
-void KItemListHeaderWidget::setColumns(const QList<QByteArray>& roles)
+void KItemListHeaderWidget::setColumns(const QList<QByteArray> &roles)
 {
-    for (const QByteArray& role : roles) {
+    for (const QByteArray &role : roles) {
         if (!m_columnWidths.contains(role)) {
             m_preferredColumnWidths.remove(role);
         }
     }
 
-    m_columns = roles;
+    m_columns = layoutDirection() == Qt::LeftToRight ? roles : reversed(roles);
     update();
 }
 
 QList<QByteArray> KItemListHeaderWidget::columns() const
 {
-    return m_columns;
+    return layoutDirection() == Qt::LeftToRight ? m_columns : reversed(m_columns);
 }
 
-void KItemListHeaderWidget::setColumnWidth(const QByteArray& role, qreal width)
+void KItemListHeaderWidget::setColumnWidth(const QByteArray &role, qreal width)
 {
     const qreal minWidth = minimumColumnWidth();
     if (width < minWidth) {
@@ -106,17 +131,17 @@ void KItemListHeaderWidget::setColumnWidth(const QByteArray& role, qreal width)
     }
 }
 
-qreal KItemListHeaderWidget::columnWidth(const QByteArray& role) const
+qreal KItemListHeaderWidget::columnWidth(const QByteArray &role) const
 {
     return m_columnWidths.value(role);
 }
 
-void KItemListHeaderWidget::setPreferredColumnWidth(const QByteArray& role, qreal width)
+void KItemListHeaderWidget::setPreferredColumnWidth(const QByteArray &role, qreal width)
 {
     m_preferredColumnWidths.insert(role, width);
 }
 
-qreal KItemListHeaderWidget::preferredColumnWidth(const QByteArray& role) const
+qreal KItemListHeaderWidget::preferredColumnWidth(const QByteArray &role) const
 {
     return m_preferredColumnWidths.value(role);
 }
@@ -134,13 +159,44 @@ qreal KItemListHeaderWidget::offset() const
     return m_offset;
 }
 
+void KItemListHeaderWidget::setSidePadding(qreal leftPaddingWidth, qreal rightPaddingWidth)
+{
+    bool changed = false;
+    if (m_leftPadding != leftPaddingWidth) {
+        m_leftPadding = leftPaddingWidth;
+        changed = true;
+    }
+
+    if (m_rightPadding != rightPaddingWidth) {
+        m_rightPadding = rightPaddingWidth;
+        changed = true;
+    }
+
+    if (!changed) {
+        return;
+    }
+
+    Q_EMIT sidePaddingChanged(leftPaddingWidth, rightPaddingWidth);
+    update();
+}
+
+qreal KItemListHeaderWidget::leftPadding() const
+{
+    return m_leftPadding;
+}
+
+qreal KItemListHeaderWidget::rightPadding() const
+{
+    return m_rightPadding;
+}
+
 qreal KItemListHeaderWidget::minimumColumnWidth() const
 {
     QFontMetricsF fontMetrics(font());
     return fontMetrics.height() * 4;
 }
 
-void KItemListHeaderWidget::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget)
+void KItemListHeaderWidget::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
 {
     Q_UNUSED(option)
     Q_UNUSED(widget)
@@ -153,9 +209,9 @@ void KItemListHeaderWidget::paint(QPainter* painter, const QStyleOptionGraphicsI
     painter->setFont(font());
     painter->setPen(palette().text().color());
 
-    qreal x = -m_offset;
+    qreal x = -m_offset + m_leftPadding + unusedSpace();
     int orderIndex = 0;
-    for (const QByteArray& role : qAsConst(m_columns)) {
+    for (const QByteArray &role : std::as_const(m_columns)) {
         const qreal roleWidth = m_columnWidths.value(role);
         const QRectF rect(x, 0, roleWidth, size().height());
         paintRole(painter, role, rect, orderIndex, widget);
@@ -164,42 +220,44 @@ void KItemListHeaderWidget::paint(QPainter* painter, const QStyleOptionGraphicsI
     }
 
     if (!m_movingRole.pixmap.isNull()) {
-        Q_ASSERT(m_roleOperation == MoveRoleOperation);
         painter->drawPixmap(m_movingRole.x, 0, m_movingRole.pixmap);
     }
 }
 
-void KItemListHeaderWidget::mousePressEvent(QGraphicsSceneMouseEvent* event)
+void KItemListHeaderWidget::mousePressEvent(QGraphicsSceneMouseEvent *event)
 {
     if (event->button() & Qt::LeftButton) {
-        updatePressedRoleIndex(event->pos());
         m_pressedMousePos = event->pos();
-        m_roleOperation = isAboveRoleGrip(m_pressedMousePos, m_pressedRoleIndex) ?
-                          ResizeRoleOperation : NoRoleOperation;
+        m_pressedGrip = isAboveResizeGrip(m_pressedMousePos);
+        if (!m_pressedGrip) {
+            updatePressedRoleIndex(event->pos());
+        }
         event->accept();
     } else {
         event->ignore();
     }
 }
 
-void KItemListHeaderWidget::mouseReleaseEvent(QGraphicsSceneMouseEvent* event)
+void KItemListHeaderWidget::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
 {
     QGraphicsWidget::mouseReleaseEvent(event);
 
-    if (m_pressedRoleIndex == -1) {
-        return;
-    }
-
-    switch (m_roleOperation) {
-    case NoRoleOperation: {
+    if (m_pressedGrip) {
+        // Emitting a column width change removes automatic column resizing, so we do not emit if only the padding is being changed.
+        // Eception: In mouseMoveEvent() we also resize the last column if the right padding is at zero but the user still quickly resizes beyond the screen
+        // boarder. Such a resize "of the right padding" is let through when automatic column resizing was disabled by that resize.
+        if (m_pressedGrip->roleToTheLeft != "leftPadding" && (m_pressedGrip->roleToTheRight != "rightPadding" || !m_automaticColumnResizing)) {
+            const qreal currentWidth = m_columnWidths.value(m_pressedGrip->roleToTheLeft);
+            Q_EMIT columnWidthChangeFinished(m_pressedGrip->roleToTheLeft, currentWidth);
+        }
+    } else if (m_pressedRoleIndex != -1 && m_movingRole.index == -1) {
         // Only a click has been done and no moving or resizing has been started
         const QByteArray sortRole = m_model->sortRole();
         const int sortRoleIndex = m_columns.indexOf(sortRole);
         if (m_pressedRoleIndex == sortRoleIndex) {
             // Toggle the sort order
             const Qt::SortOrder previous = m_model->sortOrder();
-            const Qt::SortOrder current = (m_model->sortOrder() == Qt::AscendingOrder) ?
-                                          Qt::DescendingOrder : Qt::AscendingOrder;
+            const Qt::SortOrder current = (m_model->sortOrder() == Qt::AscendingOrder) ? Qt::DescendingOrder : Qt::AscendingOrder;
             m_model->setSortOrder(current);
             Q_EMIT sortOrderChanged(current, previous);
         } else {
@@ -215,87 +273,69 @@ void KItemListHeaderWidget::mouseReleaseEvent(QGraphicsSceneMouseEvent* event)
                 Q_EMIT sortOrderChanged(Qt::AscendingOrder, Qt::DescendingOrder);
             }
         }
-        break;
     }
 
-    case ResizeRoleOperation: {
-        const QByteArray pressedRole = m_columns[m_pressedRoleIndex];
-        const qreal currentWidth = m_columnWidths.value(pressedRole);
-        Q_EMIT columnWidthChangeFinished(pressedRole, currentWidth);
-        break;
-    }
-
-    case MoveRoleOperation:
-        m_movingRole.pixmap = QPixmap();
-        m_movingRole.x = 0;
-        m_movingRole.xDec = 0;
-        m_movingRole.index = -1;
-        break;
-
-    default:
-        break;
-    }
+    m_movingRole.pixmap = QPixmap();
+    m_movingRole.x = 0;
+    m_movingRole.xDec = 0;
+    m_movingRole.index = -1;
 
+    m_pressedGrip = std::nullopt;
     m_pressedRoleIndex = -1;
-    m_roleOperation = NoRoleOperation;
     update();
 
     QApplication::restoreOverrideCursor();
 }
 
-void KItemListHeaderWidget::mouseMoveEvent(QGraphicsSceneMouseEvent* event)
+void KItemListHeaderWidget::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
 {
     QGraphicsWidget::mouseMoveEvent(event);
 
-    switch (m_roleOperation) {
-    case NoRoleOperation:
-        if ((event->pos() - m_pressedMousePos).manhattanLength() >= QApplication::startDragDistance()) {
-            // A role gets dragged by the user. Create a pixmap of the role that will get
-            // synchronized on each further mouse-move-event with the mouse-position.
-            m_roleOperation = MoveRoleOperation;
-            const int roleIndex = roleIndexAt(m_pressedMousePos);
-            m_movingRole.index = roleIndex;
-            if (roleIndex == 0) {
-                // TODO: It should be configurable whether moving the first role is allowed.
-                // In the context of Dolphin this is not required, however this should be
-                // changed if KItemViews are used in a more generic way.
-                QApplication::setOverrideCursor(QCursor(Qt::ForbiddenCursor));
-            } else {
-                m_movingRole.pixmap = createRolePixmap(roleIndex);
-
-                qreal roleX = -m_offset;
-                for (int i = 0; i < roleIndex; ++i) {
-                    const QByteArray role = m_columns[i];
-                    roleX += m_columnWidths.value(role);
-                }
+    if (m_pressedGrip) {
+        if (m_pressedGrip->roleToTheLeft == "leftPadding") {
+            qreal currentWidth = m_leftPadding;
+            currentWidth += event->pos().x() - event->lastPos().x();
+            m_leftPadding = qMax(0.0, currentWidth);
 
-                m_movingRole.xDec = event->pos().x() - roleX;
-                m_movingRole.x = roleX;
-                update();
-            }
+            update();
+            Q_EMIT sidePaddingChanged(m_leftPadding, m_rightPadding);
+            return;
         }
-        break;
 
-    case ResizeRoleOperation: {
-        const QByteArray pressedRole = m_columns[m_pressedRoleIndex];
+        if (m_pressedGrip->roleToTheRight == "rightPadding") {
+            qreal currentWidth = m_rightPadding;
+            currentWidth -= event->pos().x() - event->lastPos().x();
+            m_rightPadding = qMax(0.0, currentWidth);
 
-        qreal previousWidth = m_columnWidths.value(pressedRole);
+            update();
+            Q_EMIT sidePaddingChanged(m_leftPadding, m_rightPadding);
+            if (m_rightPadding > 0.0) {
+                return;
+            }
+            // Continue so resizing of the last column beyond the view width is possible.
+            if (currentWidth > -10) {
+                return; // Automatic column resizing is valuable, so we don't want to give it up just for a few pixels of extra width for the rightmost column.
+            }
+            m_automaticColumnResizing = false;
+        }
+
+        qreal previousWidth = m_columnWidths.value(m_pressedGrip->roleToTheLeft);
         qreal currentWidth = previousWidth;
         currentWidth += event->pos().x() - event->lastPos().x();
         currentWidth = qMax(minimumColumnWidth(), currentWidth);
 
-        m_columnWidths.insert(pressedRole, currentWidth);
+        m_columnWidths.insert(m_pressedGrip->roleToTheLeft, currentWidth);
         update();
 
-        Q_EMIT columnWidthChanged(pressedRole, currentWidth, previousWidth);
-        break;
+        Q_EMIT columnWidthChanged(m_pressedGrip->roleToTheLeft, currentWidth, previousWidth);
+        return;
     }
 
-    case MoveRoleOperation: {
+    if (m_movingRole.index != -1) {
         // TODO: It should be configurable whether moving the first role is allowed.
         // In the context of Dolphin this is not required, however this should be
         // changed if KItemViews are used in a more generic way.
-        if (m_movingRole.index > 0) {
+        if (m_movingRole.index != nameColumnIndex(this)) {
             m_movingRole.x = event->pos().x() - m_movingRole.xDec;
             update();
 
@@ -304,65 +344,92 @@ void KItemListHeaderWidget::mouseMoveEvent(QGraphicsSceneMouseEvent* event)
                 const QByteArray role = m_columns[m_movingRole.index];
                 const int previousIndex = m_movingRole.index;
                 m_movingRole.index = targetIndex;
-                Q_EMIT columnMoved(role, targetIndex, previousIndex);
+                if (layoutDirection() == Qt::LeftToRight) {
+                    Q_EMIT columnMoved(role, targetIndex, previousIndex);
+                } else {
+                    Q_EMIT columnMoved(role, m_columns.count() - 1 - targetIndex, m_columns.count() - 1 - previousIndex);
+                }
 
                 m_movingRole.xDec = event->pos().x() - roleXPosition(role);
             }
         }
-        break;
+        return;
     }
 
-    default:
-        break;
+    if ((event->pos() - m_pressedMousePos).manhattanLength() >= QApplication::startDragDistance()) {
+        // A role gets dragged by the user. Create a pixmap of the role that will get
+        // synchronized on each further mouse-move-event with the mouse-position.
+        const int roleIndex = roleIndexAt(m_pressedMousePos);
+        m_movingRole.index = roleIndex;
+        if (roleIndex == nameColumnIndex(this)) {
+            // TODO: It should be configurable whether moving the first role is allowed.
+            // In the context of Dolphin this is not required, however this should be
+            // changed if KItemViews are used in a more generic way.
+            QApplication::setOverrideCursor(QCursor(Qt::ForbiddenCursor));
+            return;
+        }
+
+        m_movingRole.pixmap = createRolePixmap(roleIndex);
+
+        qreal roleX = -m_offset + m_leftPadding + unusedSpace();
+        for (int i = 0; i < roleIndex; ++i) {
+            const QByteArray role = m_columns[i];
+            roleX += m_columnWidths.value(role);
+        }
+
+        m_movingRole.xDec = event->pos().x() - roleX;
+        m_movingRole.x = roleX;
+        update();
     }
 }
 
-void KItemListHeaderWidget::mouseDoubleClickEvent(QGraphicsSceneMouseEvent* event)
+void KItemListHeaderWidget::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)
 {
     QGraphicsItem::mouseDoubleClickEvent(event);
 
-    const int roleIndex = roleIndexAt(event->pos());
-    if (roleIndex >= 0 && isAboveRoleGrip(event->pos(), roleIndex)) {
-        const QByteArray role = m_columns.at(roleIndex);
+    const std::optional<Grip> doubleClickedGrip = isAboveResizeGrip(event->pos());
+    if (!doubleClickedGrip || doubleClickedGrip->roleToTheLeft.isEmpty()) {
+        return;
+    }
 
-        qreal previousWidth = columnWidth(role);
-        setColumnWidth(role, preferredColumnWidth(role));
-        qreal currentWidth = columnWidth(role);
+    qreal previousWidth = columnWidth(doubleClickedGrip->roleToTheLeft);
+    setColumnWidth(doubleClickedGrip->roleToTheLeft, preferredColumnWidth(doubleClickedGrip->roleToTheLeft));
+    qreal currentWidth = columnWidth(doubleClickedGrip->roleToTheLeft);
 
-        Q_EMIT columnWidthChanged(role, currentWidth, previousWidth);
-        Q_EMIT columnWidthChangeFinished(role, currentWidth);
-    }
+    Q_EMIT columnWidthChanged(doubleClickedGrip->roleToTheLeft, currentWidth, previousWidth);
+    Q_EMIT columnWidthChangeFinished(doubleClickedGrip->roleToTheLeft, currentWidth);
 }
 
-void KItemListHeaderWidget::hoverEnterEvent(QGraphicsSceneHoverEvent* event)
+void KItemListHeaderWidget::hoverEnterEvent(QGraphicsSceneHoverEvent *event)
 {
     QGraphicsWidget::hoverEnterEvent(event);
-    updateHoveredRoleIndex(event->pos());
+    updateHoveredIndex(event->pos());
 }
 
-void KItemListHeaderWidget::hoverLeaveEvent(QGraphicsSceneHoverEvent* event)
+void KItemListHeaderWidget::hoverLeaveEvent(QGraphicsSceneHoverEvent *event)
 {
     QGraphicsWidget::hoverLeaveEvent(event);
-    if (m_hoveredRoleIndex != -1) {
-        m_hoveredRoleIndex = -1;
+    if (m_hoveredIndex != -1) {
+        Q_EMIT columnUnHovered(m_hoveredIndex);
+        m_hoveredIndex = -1;
         update();
     }
 }
 
-void KItemListHeaderWidget::hoverMoveEvent(QGraphicsSceneHoverEvent* event)
+void KItemListHeaderWidget::hoverMoveEvent(QGraphicsSceneHoverEvent *event)
 {
     QGraphicsWidget::hoverMoveEvent(event);
 
-    const QPointF& pos = event->pos();
-    updateHoveredRoleIndex(pos);
-    if (m_hoveredRoleIndex >= 0 && isAboveRoleGrip(pos, m_hoveredRoleIndex)) {
+    const QPointF &pos = event->pos();
+    updateHoveredIndex(pos);
+    if (isAboveResizeGrip(pos)) {
         setCursor(Qt::SplitHCursor);
     } else {
         unsetCursor();
     }
 }
 
-void KItemListHeaderWidget::slotSortRoleChanged(const QByteArray& current, const QByteArray& previous)
+void KItemListHeaderWidget::slotSortRoleChanged(const QByteArray &current, const QByteArray &previous)
 {
     Q_UNUSED(current)
     Q_UNUSED(previous)
@@ -376,11 +443,7 @@ void KItemListHeaderWidget::slotSortOrderChanged(Qt::SortOrder current, Qt::Sort
     update();
 }
 
-void KItemListHeaderWidget::paintRole(QPainter* painter,
-                                      const QByteArray& role,
-                                      const QRectF& rect,
-                                      int orderIndex,
-                                      QWidget* widget) const
+void KItemListHeaderWidget::paintRole(QPainter *painter, const QByteArray &role, const QRectF &rect, int orderIndex, QWidget *widget) const
 {
     // The following code is based on the code from QHeaderView::paintSection().
     // SPDX-FileCopyrightText: 2011 Nokia Corporation and/or its subsidiary(-ies).
@@ -393,30 +456,49 @@ void KItemListHeaderWidget::paintRole(QPainter* painter,
     if (window() && window()->isActiveWindow()) {
         option.state |= QStyle::State_Active;
     }
-    if (m_hoveredRoleIndex == orderIndex) {
+    if (m_hoveredIndex == orderIndex) {
         option.state |= QStyle::State_MouseOver;
     }
     if (m_pressedRoleIndex == orderIndex) {
         option.state |= QStyle::State_Sunken;
     }
     if (m_model->sortRole() == role) {
-        option.sortIndicator = (m_model->sortOrder() == Qt::AscendingOrder) ?
-                                QStyleOptionHeader::SortDown : QStyleOptionHeader::SortUp;
+        option.sortIndicator = (m_model->sortOrder() == Qt::AscendingOrder) ? QStyleOptionHeader::SortDown : QStyleOptionHeader::SortUp;
     }
     option.rect = rect.toRect();
+    option.orientation = Qt::Horizontal;
+    option.selectedPosition = QStyleOptionHeader::NotAdjacent;
+    option.text = m_model->roleDescription(role);
 
-    bool paintBackgroundForEmptyArea = false;
+    // First we paint any potential empty (padding) space on left and/or right of this role's column.
+    const auto paintPadding = [&](int section, const QRectF &rect, const QStyleOptionHeader::SectionPosition &pos) {
+        QStyleOptionHeader padding;
+        padding.state = QStyle::State_None | QStyle::State_Raised | QStyle::State_Horizontal;
+        padding.section = section;
+        padding.sortIndicator = QStyleOptionHeader::None;
+        padding.rect = rect.toRect();
+        padding.position = pos;
+        padding.text = QString();
+        style()->drawControl(QStyle::CE_Header, &padding, painter, widget);
+    };
 
     if (m_columns.count() == 1) {
-        option.position = QStyleOptionHeader::OnlyOneSection;
+        option.position = QStyleOptionHeader::Middle;
+        paintPadding(0, QRectF(0.0, 0.0, rect.left(), rect.height()), QStyleOptionHeader::Beginning);
+        paintPadding(1, QRectF(rect.right(), 0.0, size().width() - rect.right(), rect.height()), QStyleOptionHeader::End);
     } else if (orderIndex == 0) {
-        option.position = QStyleOptionHeader::Beginning;
+        // Paint the header for the first column; check if there is some empty space to the left which needs to be filled.
+        if (rect.left() > 0) {
+            option.position = QStyleOptionHeader::Middle;
+            paintPadding(0, QRectF(0.0, 0.0, rect.left(), rect.height()), QStyleOptionHeader::Beginning);
+        } else {
+            option.position = QStyleOptionHeader::Beginning;
+        }
     } else if (orderIndex == m_columns.count() - 1) {
-        // We are just painting the header for the last column. Check if there
-        // is some empty space to the right which needs to be filled.
+        // Paint the header for the last column; check if there is some empty space to the right which needs to be filled.
         if (rect.right() < size().width()) {
             option.position = QStyleOptionHeader::Middle;
-            paintBackgroundForEmptyArea = true;
+            paintPadding(m_columns.count(), QRectF(rect.right(), 0.0, size().width() - rect.right(), rect.height()), QStyleOptionHeader::End);
         } else {
             option.position = QStyleOptionHeader::End;
         }
@@ -424,28 +506,10 @@ void KItemListHeaderWidget::paintRole(QPainter* painter,
         option.position = QStyleOptionHeader::Middle;
     }
 
-    option.orientation = Qt::Horizontal;
-    option.selectedPosition = QStyleOptionHeader::NotAdjacent;
-    option.text = m_model->roleDescription(role);
-
     style()->drawControl(QStyle::CE_Header, &option, painter, widget);
-
-    if (paintBackgroundForEmptyArea) {
-        option.state = QStyle::State_None | QStyle::State_Raised | QStyle::State_Horizontal;
-        option.section = m_columns.count();
-        option.sortIndicator = QStyleOptionHeader::None;
-
-        qreal backgroundRectX = rect.x() + rect.width();
-        QRectF backgroundRect(backgroundRectX, 0.0, size().width() - backgroundRectX, rect.height());
-        option.rect = backgroundRect.toRect();
-        option.position = QStyleOptionHeader::End;
-        option.text = QString();
-
-        style()->drawControl(QStyle::CE_Header, &option, painter, widget);
-    }
 }
 
-void KItemListHeaderWidget::updatePressedRoleIndex(const QPointF& pos)
+void KItemListHeaderWidget::updatePressedRoleIndex(const QPointF &pos)
 {
     const int pressedIndex = roleIndexAt(pos);
     if (m_pressedRoleIndex != pressedIndex) {
@@ -454,41 +518,61 @@ void KItemListHeaderWidget::updatePressedRoleIndex(const QPointF& pos)
     }
 }
 
-void KItemListHeaderWidget::updateHoveredRoleIndex(const QPointF& pos)
+void KItemListHeaderWidget::updateHoveredIndex(const QPointF &pos)
 {
-    const int hoverIndex = roleIndexAt(pos);
-    if (m_hoveredRoleIndex != hoverIndex) {
-        m_hoveredRoleIndex = hoverIndex;
+    const int hoverIndex = isAboveResizeGrip(pos) ? -1 : roleIndexAt(pos);
+
+    if (m_hoveredIndex != hoverIndex) {
+        if (m_hoveredIndex != -1) {
+            Q_EMIT columnUnHovered(m_hoveredIndex);
+        }
+        m_hoveredIndex = hoverIndex;
+        if (m_hoveredIndex != -1) {
+            Q_EMIT columnHovered(m_hoveredIndex);
+        }
         update();
     }
 }
 
-int KItemListHeaderWidget::roleIndexAt(const QPointF& pos) const
+int KItemListHeaderWidget::roleIndexAt(const QPointF &pos) const
 {
-    int index = -1;
+    qreal x = -m_offset + m_leftPadding + unusedSpace();
+    if (pos.x() < x) {
+        return -1;
+    }
 
-    qreal x = -m_offset;
-    for (const QByteArray& role : qAsConst(m_columns)) {
+    int index = -1;
+    for (const QByteArray &role : std::as_const(m_columns)) {
         ++index;
         x += m_columnWidths.value(role);
         if (pos.x() <= x) {
-            break;
+            return index;
         }
     }
 
-    return index;
+    return -1;
 }
 
-bool KItemListHeaderWidget::isAboveRoleGrip(const QPointF& pos, int roleIndex) const
+std::optional<const KItemListHeaderWidget::Grip> KItemListHeaderWidget::isAboveResizeGrip(const QPointF &position) const
 {
-    qreal x = -m_offset;
-    for (int i = 0; i <= roleIndex; ++i) {
+    qreal x = -m_offset + m_leftPadding + unusedSpace();
+    const int gripWidthTolerance = style()->pixelMetric(QStyle::PM_HeaderGripMargin);
+
+    if (x - gripWidthTolerance < position.x() && position.x() < x + gripWidthTolerance) {
+        return std::optional{Grip{"leftPadding", m_columns[0]}};
+    }
+
+    for (int i = 0; i < m_columns.count(); ++i) {
         const QByteArray role = m_columns[i];
         x += m_columnWidths.value(role);
+        if (x - gripWidthTolerance < position.x() && position.x() < x + gripWidthTolerance) {
+            if (i + 1 < m_columns.count()) {
+                return std::optional{Grip{m_columns[i], m_columns[i + 1]}};
+            }
+            return std::optional{Grip{m_columns[i], "rightPadding"}};
+        }
     }
-
-    const int grip = style()->pixelMetric(QStyle::PM_HeaderGripMargin);
-    return pos.x() >= (x - grip) && pos.x() <= x;
+    return std::nullopt;
 }
 
 QPixmap KItemListHeaderWidget::createRolePixmap(int roleIndex) const
@@ -522,18 +606,14 @@ int KItemListHeaderWidget::targetOfMovingRole() const
     const int movingRight = movingLeft + movingWidth - 1;
 
     int targetIndex = 0;
-    qreal targetLeft = -m_offset;
+    qreal targetLeft = -m_offset + m_leftPadding + unusedSpace();
     while (targetIndex < m_columns.count()) {
         const QByteArray role = m_columns[targetIndex];
         const qreal targetWidth = m_columnWidths.value(role);
         const qreal targetRight = targetLeft + targetWidth - 1;
 
-        const bool isInTarget = (targetWidth >= movingWidth &&
-                                 movingLeft  >= targetLeft  &&
-                                 movingRight <= targetRight) ||
-                                (targetWidth <  movingWidth &&
-                                 movingLeft  <= targetLeft  &&
-                                 movingRight >= targetRight);
+        const bool isInTarget = (targetWidth >= movingWidth && movingLeft >= targetLeft && movingRight <= targetRight)
+            || (targetWidth < movingWidth && movingLeft <= targetLeft && movingRight >= targetRight);
 
         if (isInTarget) {
             return targetIndex;
@@ -546,10 +626,10 @@ int KItemListHeaderWidget::targetOfMovingRole() const
     return m_movingRole.index;
 }
 
-qreal KItemListHeaderWidget::roleXPosition(const QByteArray& role) const
+qreal KItemListHeaderWidget::roleXPosition(const QByteArray &role) const
 {
-    qreal x = -m_offset;
-    for (const QByteArray& visibleRole : qAsConst(m_columns)) {
+    qreal x = -m_offset + m_leftPadding + unusedSpace();
+    for (const QByteArray &visibleRole : std::as_const(m_columns)) {
         if (visibleRole == role) {
             return x;
         }
@@ -560,3 +640,17 @@ qreal KItemListHeaderWidget::roleXPosition(const QByteArray& role) const
     return -1;
 }
 
+qreal KItemListHeaderWidget::unusedSpace() const
+{
+    if (layoutDirection() == Qt::LeftToRight) {
+        return 0;
+    }
+    int unusedSpace = size().width() - m_leftPadding - m_rightPadding;
+    for (int i = 0; i < m_columns.count(); ++i) {
+        const QByteArray role = m_columns[i];
+        unusedSpace -= m_columnWidths.value(role);
+    }
+    return qMax(unusedSpace, 0);
+}
+
+#include "moc_kitemlistheaderwidget.cpp"