VerticalTabs: Fix QSS styling issues

It is now possible to replicate tabbar from Windows theme.

src/plugins/VerticalTabs/tablistdelegate.cpp

@@ -52,9 +52,8 @@ void TabListDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
     const QStyle *style = w ? w->style() : m_view->style();
 
     QStyleOptionViewItem opt = option;
-    opt.state.setFlag(QStyle::State_Active, true);
+    initStyleOption(&opt, index);
-    opt.state.setFlag(QStyle::State_HasFocus, false);
+    m_view->adjustStyleOption(&opt);
-    opt.state.setFlag(QStyle::State_Selected, index.data(TabModel::CurrentTabRole).toBool());
 
     const int height = opt.rect.height();
     const int center = height / 2 + opt.rect.top();
@@ -91,7 +90,6 @@ void TabListDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
         painter->drawEllipse(audioRect);
 
         painter->drawPixmap(audioRect, audioMuted ? TabIcon::data()->audioMutedPixmap : TabIcon::data()->audioPlayingPixmap);
-
     }
 }
 

src/plugins/VerticalTabs/tablistview.cpp

@@ -45,6 +45,30 @@ TabListView::TabListView(QWidget *parent)
     setFixedHeight(m_delegate->sizeHint(viewOptions(), QModelIndex()).height());
 }
 
+void TabListView::adjustStyleOption(QStyleOptionViewItem *option)
+{
+    const QModelIndex index = option->index;
+
+    option->state.setFlag(QStyle::State_Active, true);
+    option->state.setFlag(QStyle::State_HasFocus, false);
+    option->state.setFlag(QStyle::State_Selected, index.data(TabModel::CurrentTabRole).toBool());
+
+    if (!index.isValid()) {
+        option->viewItemPosition = QStyleOptionViewItem::Invalid;
+    } else if (model()->rowCount() == 1) {
+        option->viewItemPosition = QStyleOptionViewItem::OnlyOne;
+    } else {
+        const QRect rect = visualRect(index);
+        if (!indexAt(QPoint(rect.x() - rect.width() / 2, rect.y())).isValid()) {
+            option->viewItemPosition = QStyleOptionViewItem::Beginning;
+        } else if (!indexAt(QPoint(rect.x() + rect.width() / 2, rect.y())).isValid()) {
+            option->viewItemPosition = QStyleOptionViewItem::End;
+        } else {
+            option->viewItemPosition = QStyleOptionViewItem::Middle;
+        }
+    }
+}
+
 void TabListView::currentChanged(const QModelIndex &current, const QModelIndex &previous)
 {
     if (current.data(TabModel::CurrentTabRole).toBool()) {

src/plugins/VerticalTabs/tablistview.h

@@ -28,6 +28,8 @@ class TabListView : public QListView
 public:
     explicit TabListView(QWidget *parent = nullptr);
 
+    void adjustStyleOption(QStyleOptionViewItem *option);
+
 private:
     void currentChanged(const QModelIndex &current, const QModelIndex &previous) override;
     void dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles = QVector<int>()) override;

src/plugins/VerticalTabs/tabtreedelegate.cpp

@@ -100,9 +100,8 @@ void TabTreeDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
     const int depth = indexDepth(index);
 
     QStyleOptionViewItem opt = option;
-    opt.state.setFlag(QStyle::State_Active, true);
+    initStyleOption(&opt, index);
-    opt.state.setFlag(QStyle::State_HasFocus, false);
+    m_view->adjustStyleOption(&opt);
-    opt.state.setFlag(QStyle::State_Selected, index.data(TabModel::CurrentTabRole).toBool());
 
     const int height = opt.rect.height();
     const int center = height / 2 + opt.rect.top();
@@ -184,6 +183,11 @@ void TabTreeDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
     QRect titleRect(leftPosition, center - opt.fontMetrics.height() / 2, opt.rect.width(), opt.fontMetrics.height());
     titleRect.setRight(rightPosition - m_padding);
     QString title = opt.fontMetrics.elidedText(index.data().toString(), Qt::ElideRight, titleRect.width());
+    if (opt.state.testFlag(QStyle::State_Selected) && m_view->selectedColor().isValid()) {
+        textPalette.setColor(cg, colorRole, m_view->selectedColor());
+    } else if (opt.state.testFlag(QStyle::State_MouseOver) && m_view->hoverColor().isValid()) {
+        textPalette.setColor(cg, colorRole, m_view->hoverColor());
+    }
     style->drawItemText(painter, titleRect, Qt::AlignLeft, textPalette, true, title, colorRole);
 }
 

src/plugins/VerticalTabs/tabtreeview.cpp

@@ -51,6 +51,26 @@ TabTreeView::TabTreeView(QWidget *parent)
     viewport()->setAttribute(Qt::WA_Hover);
 }
 
+QColor TabTreeView::hoverColor() const
+{
+    return m_hoverColor;
+}
+
+void TabTreeView::setHoverColor(const QColor &color)
+{
+    m_hoverColor = color;
+}
+
+QColor TabTreeView::selectedColor() const
+{
+    return m_selectedColor;
+}
+
+void TabTreeView::setSelectedColor(const QColor &color)
+{
+    m_selectedColor = color;
+}
+
 bool TabTreeView::areTabsInOrder() const
 {
     return m_tabsInOrder;
@@ -61,6 +81,29 @@ void TabTreeView::setTabsInOrder(bool enable)
     m_tabsInOrder = enable;
 }
 
+void TabTreeView::adjustStyleOption(QStyleOptionViewItem *option)
+{
+    const QModelIndex index = option->index;
+
+    option->state.setFlag(QStyle::State_Active, true);
+    option->state.setFlag(QStyle::State_HasFocus, false);
+    option->state.setFlag(QStyle::State_Selected, index.data(TabModel::CurrentTabRole).toBool());
+
+    if (!index.isValid()) {
+        option->viewItemPosition = QStyleOptionViewItem::Invalid;
+    } else if (model()->rowCount() == 1) {
+        option->viewItemPosition = QStyleOptionViewItem::OnlyOne;
+    } else {
+        if (!indexAbove(index).isValid()) {
+            option->viewItemPosition = QStyleOptionViewItem::Beginning;
+        } else if (!indexBelow(index).isValid()) {
+            option->viewItemPosition = QStyleOptionViewItem::End;
+        } else {
+            option->viewItemPosition = QStyleOptionViewItem::Middle;
+        }
+    }
+}
+
 void TabTreeView::drawBranches(QPainter *, const QRect &, const QModelIndex &) const
 {
     // Disable drawing branches

src/plugins/VerticalTabs/tabtreeview.h

@@ -24,14 +24,24 @@ class TabTreeDelegate;
 class TabTreeView : public QTreeView
 {
     Q_OBJECT
+    Q_PROPERTY(QColor hoverColor READ hoverColor WRITE setHoverColor)
+    Q_PROPERTY(QColor selectedColor READ selectedColor WRITE setSelectedColor)
 
 public:
     explicit TabTreeView(QWidget *parent = nullptr);
 
+    QColor hoverColor() const;
+    void setHoverColor(const QColor &color);
+
+    QColor selectedColor() const;
+    void setSelectedColor(const QColor &color);
+
     // In TabBar order
     bool areTabsInOrder() const;
     void setTabsInOrder(bool enable);
 
+    void adjustStyleOption(QStyleOptionViewItem *option);
+
 private:
     void drawBranches(QPainter *painter, const QRect &rect, const QModelIndex &index) const override;
     void currentChanged(const QModelIndex &current, const QModelIndex &previous) override;
@@ -48,6 +58,9 @@ private:
 
     DelegateButton buttonAt(const QPoint &pos, const QModelIndex &index) const;
 
+    QColor m_hoverColor;
+    QColor m_selectedColor;
+
     TabTreeDelegate *m_delegate;
     DelegateButton m_pressedButton = NoButton;
     QPersistentModelIndex m_pressedIndex;