1 files changed, 80 insertions, 0 deletions
diff --git a/libs/installer_bsplugins/src/GUI/ViewMarkingScrollBar.cpp b/libs/installer_bsplugins/src/GUI/ViewMarkingScrollBar.cpp
new file mode 100644
index 0000000..94da308
--- /dev/null
+++ b/libs/installer_bsplugins/src/GUI/ViewMarkingScrollBar.cpp
@@ -0,0 +1,80 @@
+#include "ViewMarkingScrollBar.h"
+
+#include <QPainter>
+#include <QStyle>
+#include <QStyleOptionSlider>
+
+namespace GUI
+{
+
+static QModelIndexList visibleIndexImpl(QTreeView* view, int column,
+                                        const QModelIndex& parent)
+{
+  if (parent.isValid() && !view->isExpanded(parent)) {
+    return {};
+  }
+
+  const auto* const model = view->model();
+  QModelIndexList index;
+  for (int i = 0; i < model->rowCount(parent); ++i) {
+    index.append(model->index(i, column, parent));
+    index.append(visibleIndexImpl(view, column, index.back()));
+  }
+  return index;
+}
+
+static QModelIndexList visibleIndex(QTreeView* view, int column)
+{
+  return visibleIndexImpl(view, column, QModelIndex());
+}
+
+ViewMarkingScrollBar::ViewMarkingScrollBar(QTreeView* view, int role)
+    : QScrollBar(view), m_View{view}, m_Role{role}
+{
+  // not implemented for horizontal sliders
+  Q_ASSERT(this->orientation() == Qt::Vertical);
+}
+
+QColor ViewMarkingScrollBar::color(const QModelIndex& index) const
+{
+  const auto data = index.data(m_Role);
+  if (data.canConvert<QColor>()) {
+    return data.value<QColor>();
+  }
+  return QColor();
+}
+
+void ViewMarkingScrollBar::paintEvent(QPaintEvent* event)
+{
+  if (m_View->model() == nullptr) {
+    return;
+  }
+  QScrollBar::paintEvent(event);
+
+  QStyleOptionSlider styleOption;
+  initStyleOption(&styleOption);
+
+  QPainter painter(this);
+
+  QRect handleRect = style()->subControlRect(QStyle::CC_ScrollBar, &styleOption,
+                                             QStyle::SC_ScrollBarSlider, this);
+  QRect innerRect  = style()->subControlRect(QStyle::CC_ScrollBar, &styleOption,
+                                             QStyle::SC_ScrollBarGroove, this);
+
+  auto indices = visibleIndex(m_View, 0);
+
+  painter.translate(innerRect.topLeft() + QPoint(0, 3));
+  const qreal scale =
+      static_cast<qreal>(innerRect.height() - 3) / static_cast<qreal>(indices.size());
+
+  for (int i = 0; i < indices.size(); ++i) {
+    const QColor color = this->color(indices[i]);
+    if (color.isValid()) {
+      painter.setPen(color);
+      painter.setBrush(color);
+      painter.drawRect(QRect(2, i * scale - 2, handleRect.width() - 5, 3));
+    }
+  }
+}
+
+}  // namespace GUI