LibGUI: Grow spacers after doing layout

Before this, the spacers were handled as just another child widget, and
as such could take away space from real widgets when growing.
This also fixes the problem of effectively 0 sized spacers, that doubled
the spacing between the widgets they were placed between.

1 files changed, 20 insertions, 7 deletions

diff --git a/Userland/Libraries/LibGUI/BoxLayout.cpp b/Userland/Libraries/LibGUI/BoxLayout.cpp
index 49ec9f2cd0..0416ef887a 100644
--- a/Userland/Libraries/LibGUI/BoxLayout.cpp
+++ b/Userland/Libraries/LibGUI/BoxLayout.cpp
@@ -151,6 +151,7 @@ void BoxLayout::run(Widget& widget)
     };
 
     Vector<Item, 32> items;
+    int spacer_count = 0;
     int opportunistic_growth_item_count = 0;
     int opportunistic_growth_items_base_size_total = 0;
 
@@ -158,6 +159,7 @@ void BoxLayout::run(Widget& widget)
         auto& entry = m_entries[i];
         if (entry.type == Entry::Type::Spacer) {
             items.append(Item { nullptr, { SpecialDimension::Shrink }, { SpecialDimension::Grow }, { SpecialDimension::Grow } });
+            spacer_count++;
             continue;
         }
         if (!entry.widget)
@@ -188,9 +190,9 @@ void BoxLayout::run(Widget& widget)
 
     Gfx::IntRect content_rect = widget.content_rect();
     int uncommitted_size = content_rect.size().primary_size_for_orientation(orientation())
-        - spacing() * (items.size() - 1)
+        - spacing() * (items.size() - 1 - spacer_count)
         - margins().primary_total_for_orientation(orientation());
-    int unfinished_regular_items = items.size() - opportunistic_growth_item_count;
+    int unfinished_regular_items = items.size() - spacer_count - opportunistic_growth_item_count;
     int max_amongst_the_min_sizes = 0;
     int max_amongst_the_min_sizes_of_opportunistically_growing_items = 0;
     int regular_items_to_layout = 0;
@@ -347,6 +349,12 @@ void BoxLayout::run(Widget& widget)
         }
     }
 
+    // Determine size of the spacers, according to the still uncommitted size
+    int spacer_width = 0;
+    if (spacer_count > 0 && uncommitted_size > 0) {
+        spacer_width = uncommitted_size / spacer_count;
+    }
+
     // Pass 6: Place the widgets.
     int current_x = margins().left() + content_rect.x();
     int current_y = margins().top() + content_rect.y();
@@ -380,12 +388,17 @@ void BoxLayout::run(Widget& widget)
                 rect.center_horizontally_within(widget_rect_with_margins_subtracted);
 
             item.widget->set_relative_rect(rect);
-        }
 
-        if (orientation() == Gfx::Orientation::Horizontal)
-            current_x += rect.width() + spacing();
-        else
-            current_y += rect.height() + spacing();
+            if (orientation() == Gfx::Orientation::Horizontal)
+                current_x += rect.width() + spacing();
+            else
+                current_y += rect.height() + spacing();
+        } else {
+            if (orientation() == Gfx::Orientation::Horizontal)
+                current_x += spacer_width;
+            else
+                current_y += spacer_width;
+        }
     }
 }