LibGUI: Add basic rubber band selection in GItemView

2 files changed, 47 insertions, 0 deletions

diff --git a/Libraries/LibGUI/GItemView.cpp b/Libraries/LibGUI/GItemView.cpp
index 31c69d3299..364c72f579 100644
--- a/Libraries/LibGUI/GItemView.cpp
+++ b/Libraries/LibGUI/GItemView.cpp
@@ -91,6 +91,9 @@ void GItemView::mousedown_event(GMouseEvent& event)
         m_left_mousedown_position = event.position();
         if (item_index == -1) {
             selection().clear();
+            m_rubber_banding = true;
+            m_rubber_band_origin = event.position();
+            m_rubber_band_current = event.position();
         } else {
             auto index = model()->index(item_index, m_model_column);
             if (event.modifiers() & Mod_Ctrl)
@@ -103,11 +106,36 @@ void GItemView::mousedown_event(GMouseEvent& event)
     GAbstractView::mousedown_event(event);
 }
 
+void GItemView::mouseup_event(GMouseEvent& event)
+{
+    if (m_rubber_banding && event.button() == GMouseButton::Left) {
+        m_rubber_banding = false;
+        update();
+        return;
+    }
+    GAbstractView::mouseup_event(event);
+}
+
 void GItemView::mousemove_event(GMouseEvent& event)
 {
     if (!model())
         return GAbstractView::mousemove_event(event);
 
+    if (m_rubber_banding) {
+        if (m_rubber_band_current != event.position()) {
+            m_rubber_band_current = event.position();
+            auto rubber_band_rect = Rect::from_two_points(m_rubber_band_origin, m_rubber_band_current);
+            selection().clear();
+            for (int row_index = 0, row_count = model()->row_count(); row_index < row_count; ++row_index) {
+                auto item_rect = this->item_rect(row_index);
+                if (item_rect.intersects(rubber_band_rect))
+                    selection().add(model()->index(row_index, model_column()));
+            }
+            update();
+            return;
+        }
+    }
+
     if (event.buttons() & GMouseButton::Left && !selection().is_empty()) {
         auto diff = event.position() - m_left_mousedown_position;
         auto distance_travelled_squared = diff.x() * diff.x() + diff.y() * diff.y();
@@ -187,6 +215,19 @@ void GItemView::doubleclick_event(GMouseEvent& event)
     }
 }
 
+void GItemView::second_paint_event(GPaintEvent& event)
+{
+    if (!m_rubber_banding)
+        return;
+
+    GPainter painter(*this);
+    painter.add_clip_rect(event.rect());
+
+    auto rubber_band_rect = Rect::from_two_points(m_rubber_band_origin, m_rubber_band_current);
+    painter.fill_rect(rubber_band_rect, Color(244, 202, 158, 60));
+    painter.draw_rect(rubber_band_rect, Color(110, 34, 9));
+}
+
 void GItemView::paint_event(GPaintEvent& event)
 {
     Color widget_background_color = palette().color(background_role());
diff --git a/Libraries/LibGUI/GItemView.h b/Libraries/LibGUI/GItemView.h
index 7650775d06..7e8851acac 100644
--- a/Libraries/LibGUI/GItemView.h
+++ b/Libraries/LibGUI/GItemView.h
@@ -27,9 +27,11 @@ private:
 
     virtual void did_update_model() override;
     virtual void paint_event(GPaintEvent&) override;
+    virtual void second_paint_event(GPaintEvent&) override;
     virtual void resize_event(GResizeEvent&) override;
     virtual void mousedown_event(GMouseEvent&) override;
     virtual void mousemove_event(GMouseEvent&) override;
+    virtual void mouseup_event(GMouseEvent&) override;
     virtual void keydown_event(GKeyEvent&) override;
     virtual void doubleclick_event(GMouseEvent&) override;
     virtual void context_menu_event(GContextMenuEvent&) override;
@@ -47,4 +49,8 @@ private:
     Point m_left_mousedown_position;
 
     Size m_effective_item_size { 80, 80 };
+
+    bool m_rubber_banding { false };
+    Point m_rubber_band_origin;
+    Point m_rubber_band_current;
 };