LibGUI: Implement calculated_min_size() for ListView

Userland/Libraries/LibGUI/ListView.cpp

@@ -44,7 +44,7 @@ void ListView::update_content_size()
         auto text = model()->index(row, m_model_column).data();
         content_width = max(content_width, font().width(text.to_string()) + horizontal_padding() * 2);
     }
-
+    m_max_item_width = content_width;
     content_width = max(content_width, widget_inner_rect().width());
 
     int content_height = item_count() * item_height();
@@ -268,4 +268,15 @@ void ListView::scroll_into_view(ModelIndex const& index, bool scroll_horizontall
     AbstractScrollableWidget::scroll_into_view(content_rect(index.row()), scroll_horizontally, scroll_vertically);
 }
 
+Optional<UISize> ListView::calculated_min_size() const
+{
+    auto min_width = horizontal_scrollbar().effective_min_size().width().as_int() + vertical_scrollbar().width() + frame_thickness() * 2;
+    auto min_height = vertical_scrollbar().effective_min_size().height().as_int() + horizontal_scrollbar().height() + frame_thickness() * 2;
+    auto content_exceeds_minimums = content_width() > min_width && content_height() > min_height;
+    auto scrollbars_are_visible = horizontal_scrollbar().is_visible() && vertical_scrollbar().is_visible();
+    if (content_exceeds_minimums || scrollbars_are_visible)
+        return AbstractScrollableWidget::calculated_min_size();
+    return { { m_max_item_width + frame_thickness() * 2, content_height() + frame_thickness() * 2 } };
+}
+
 }

Userland/Libraries/LibGUI/ListView.h

@@ -56,12 +56,15 @@ private:
     virtual void mousemove_event(MouseEvent&) override;
     virtual void layout_relevant_change_occured() override;
 
+    virtual Optional<UISize> calculated_min_size() const override;
+
     Gfx::IntRect content_rect(int row) const;
     void update_content_size();
 
     int m_horizontal_padding { 2 };
     int m_vertical_padding { 2 };
     int m_model_column { 0 };
+    int m_max_item_width { 0 };
     bool m_alternating_row_colors { true };
     bool m_hover_highlighting { false };
 };