Add a minimum cross axis size to BoxLayout.

This CL allows clients to specify a minimum cross axis size when using
a BoxLayout.

BUG=406983

Review URL: https://codereview.chromium.org/494273003

Cr-Commit-Position: refs/heads/master@{#292299}

ui/views/layout/box_layout.cc

@@ -22,6 +22,7 @@ BoxLayout::BoxLayout(BoxLayout::Orientation orientation,
       main_axis_alignment_(MAIN_AXIS_ALIGNMENT_START),
       cross_axis_alignment_(CROSS_AXIS_ALIGNMENT_STRETCH),
       default_flex_(0),
+      minimum_cross_axis_size_(0),
       host_(NULL) {
 }
 
@@ -162,6 +163,7 @@ gfx::Size BoxLayout::GetPreferredSize(const View* host) const {
 
       width = std::max(width, child->GetPreferredSize().width());
     }
+    width = std::max(width, minimum_cross_axis_size_);
   }
 
   return GetPreferredSizeForChildWidth(host, width);
@@ -278,6 +280,8 @@ gfx::Size BoxLayout::GetPreferredSizeForChildWidth(const View* host,
       child_area_bounds.Union(child_bounds);
       position += size.width() + between_child_spacing_;
     }
+    child_area_bounds.set_height(
+        std::max(child_area_bounds.height(), minimum_cross_axis_size_));
   } else {
     int height = 0;
     for (int i = 0; i < host->child_count(); ++i) {

ui/views/layout/box_layout.h

@@ -77,6 +77,10 @@ class VIEWS_EXPORT BoxLayout : public LayoutManager {
     inside_border_insets_ = insets;
   }
 
+  void set_minimum_cross_axis_size(int size) {
+    minimum_cross_axis_size_ = size;
+  }
+
   // Sets the flex weight for the given |view|. Using the preferred size as
   // the basis, free space along the main axis is distributed to views in the
   // ratio of their flex weights. Similarly, if the views will overflow the
@@ -159,6 +163,9 @@ class VIEWS_EXPORT BoxLayout : public LayoutManager {
   // The flex weight for views if none is set. Defaults to 0.
   int default_flex_;
 
+  // The minimum cross axis size for the layout.
+  int minimum_cross_axis_size_;
+
   // The view that this BoxLayout is managing the layout for.
   views::View* host_;
 

ui/views/layout/box_layout_unittest.cc

@@ -590,4 +590,24 @@ TEST_F(BoxLayoutTest, FlexShrinkVerticalWithRemainder) {
   }
 }
 
+TEST_F(BoxLayoutTest, MinimumCrossAxisVertical) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kVertical, 0, 0, 0);
+  host_->SetLayoutManager(layout);
+  View* v1 = new StaticSizedView(gfx::Size(20, 10));
+  host_->AddChildView(v1);
+  layout->set_minimum_cross_axis_size(30);
+
+  EXPECT_EQ(gfx::Size(30, 10), layout->GetPreferredSize(host_.get()));
+}
+
+TEST_F(BoxLayoutTest, MinimumCrossAxisHorizontal) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 0, 0, 0);
+  host_->SetLayoutManager(layout);
+  View* v1 = new StaticSizedView(gfx::Size(20, 10));
+  host_->AddChildView(v1);
+  layout->set_minimum_cross_axis_size(30);
+
+  EXPECT_EQ(gfx::Size(20, 30), layout->GetPreferredSize(host_.get()));
+}
+
 }  // namespace views