Show the current selection in the overlay scrollbar.

Change-Id: Ie92b7ae170938eac71ede751d9067e1d47293092
Reviewed-on: https://code.wireshark.org/review/9750
Reviewed-by: Gerald Combs <gerald@wireshark.org>

ui/qt/overlay_scroll_bar.cpp

@@ -32,7 +32,8 @@
 OverlayScrollBar::OverlayScrollBar(Qt::Orientation orientation, QWidget *parent) :
     QScrollBar(orientation, parent = 0),
     near_overlay_(QImage()),
-    far_overlay_(QImage())
+    far_overlay_(QImage()),
+    selected_pos_(-1)
 {}
 
 QSize OverlayScrollBar::sizeHint() const
@@ -40,9 +41,10 @@ QSize OverlayScrollBar::sizeHint() const
     return QSize(QScrollBar::sizeHint().width() + (far_overlay_.width() * 2), QScrollBar::sizeHint().height());
 }
 
-void OverlayScrollBar::setNearOverlayImage(QImage &overlay_image)
+void OverlayScrollBar::setNearOverlayImage(QImage &overlay_image, int selected_pos)
 {
     near_overlay_ = overlay_image;
+    selected_pos_ = selected_pos;
     update();
 }
 
@@ -89,6 +91,17 @@ void OverlayScrollBar::paintEvent(QPaintEvent *event)
             far_dest.moveLeft(gr_size.width() - fo_width);
             go_painter.drawImage(far_dest, far_overlay_.mirrored(true, false));
         }
+
+        // Selected packet indicator
+        if (selected_pos_ >= 0 && selected_pos_ < near_overlay_.height()) {
+            int no_pos = near_dest.height() * selected_pos_ / near_overlay_.height();
+            go_painter.save();
+            go_painter.setBrush(palette().highlight().color());
+            go_painter.drawRect(0, no_pos, near_dest.width(), devicePixelRatio());
+            go_painter.restore();
+        }
+
+        // Outline
         QRect near_outline(near_dest);
         near_outline.adjust(0, 0, -1, -1);
         go_painter.save();
@@ -98,21 +111,6 @@ void OverlayScrollBar::paintEvent(QPaintEvent *event)
         go_painter.drawRect(near_outline);
         go_painter.restore();
 
-#if 0
-        // Fade in from the left and right.
-        go_painter.save();
-        go_painter.setCompositionMode(QPainter::CompositionMode_DestinationIn);
-        QLinearGradient fade(0, 0, groove_overlay.width(), 0);
-        fade.setColorAt(0, Qt::transparent);
-        fade.setColorAt(0.2, Qt::white);
-        fade.setColorAt(0.8, Qt::white);
-        fade.setColorAt(1, Qt::transparent);
-
-        go_painter.setBrush(fade);
-        go_painter.drawRect(groove_overlay.rect());
-        go_painter.restore();
-#endif
-
         // Punch a hole for the slider.
         QStyleOptionSlider opt;
         initStyleOption(&opt);

ui/qt/overlay_scroll_bar.h

@@ -33,8 +33,18 @@ public:
 
     virtual QSize sizeHint() const;
 
-    // Images are assumed to be 1 pixel wide and grooveRect.height() high.
-    void setNearOverlayImage(QImage &overlay_image);
+    /** Set the "near" overlay image.
+     * @param overlay_image An image containing a 1:1 mapping of nearby
+     *        packet colors to raster lines.
+     * @param selected_pos The position of the selected packet within the
+     *        image. -1 means no packet is selected.
+     */
+    void setNearOverlayImage(QImage &overlay_image, int selected_pos = -1);
+
+    /** Set the "far" overlay image.
+     * @param overlay_image An image showing the position of marked, ignored,
+     *        and reference time packets over the entire packet list.
+     */
     void setFarOverlayImage(QImage &overlay_image);
     QRect grooveRect();
 
@@ -44,6 +54,7 @@ protected:
 private:
     QImage near_overlay_;
     QImage far_overlay_;
+    int selected_pos_;
 };
 
 #endif // __OVERLAY_SCROLL_BAR_H__

ui/qt/packet_list.cpp

@@ -1312,6 +1312,7 @@ void PacketList::drawNearOverlay()
 #endif
     int o_height = overlay_sb_->height() * dp_ratio * height_multiplier_;
     int o_rows = qMin(packet_list_model_->rowCount(), o_height);
+    int selected_pos = -1;
 
     if (recent.packet_list_colorize && o_rows > 0) {
         QImage overlay(1, o_height, QImage::Format_ARGB32_Premultiplied);
@@ -1363,7 +1364,18 @@ void PacketList::drawNearOverlay()
             cur_line = next_line;
         }
 
-        overlay_sb_->setNearOverlayImage(overlay);
+        if (selectionModel()->hasSelection()) {
+            int sel_row = selectionModel()->currentIndex().row();
+            if (sel_row < start) {
+                selected_pos = 0;
+            } else if (sel_row >= end) {
+                selected_pos = overlay.height() - 1;
+            } else {
+                selected_pos = sel_row * overlay.height() / packet_list_model_->rowCount();
+            }
+        }
+
+        overlay_sb_->setNearOverlayImage(overlay, selected_pos);
     } else {
         QImage overlay;
         overlay_sb_->setNearOverlayImage(overlay);