Add {Get,Set}ItemVisible() accessors and setters.

headers/os/interface/SplitView.h

@@ -48,6 +48,9 @@ public:
 			void				SetCollapsible(int32 first, int32 last,
 									bool collapsible);
 
+			bool				GetItemVisible(int32 index) const;
+			void				SetItemVisible(int32 index, bool visible);
+
 //			void				AddChild(BView* child);
 			void				AddChild(BView* child, BView* sibling = NULL);
 			bool				AddChild(BView* child, float weight);

src/kits/interface/SplitLayout.cpp

@@ -465,6 +465,11 @@ BSplitLayout::SetItemWeight(BLayoutItem* item, float weight)
 bool
 BSplitLayout::GetCollapsible(int32 index) const
 {
+	if (index < 0)
+		index = 0;
+	if (index > CountItems())
+		index = CountItems() - 1;
+
 	return _ItemLayoutInfo(ItemAt(index))->isCollapsible;
 }
 
@@ -496,6 +501,32 @@ BSplitLayout::SetCollapsible(int32 first, int32 last, bool collapsible)
 }
 
 
+bool
+BSplitLayout::GetItemVisible(int32 index) const
+{
+	if (index < 0)
+		index = 0;
+	if (index > CountItems())
+		index = CountItems() - 1;
+
+	return _ItemLayoutInfo(ItemAt(index))->isVisible;
+}
+
+
+void
+BSplitLayout::SetItemVisible(int32 index, bool visible)
+{
+	if (index < 0)
+		index = 0;
+	if (index > CountItems())
+		index = CountItems() - 1;
+
+	ItemAt(index)->SetVisible(visible);
+
+	InvalidateLayout(true);
+}
+
+
 BSize
 BSplitLayout::BaseMinSize()
 {

src/kits/interface/SplitLayout.h

@@ -67,6 +67,9 @@ public:
 			void				SetCollapsible(int32 first, int32 last,
 									bool collapsible);
 
+			bool				GetItemVisible(int32 index) const;
+			void				SetItemVisible(int32 index, bool visible);
+
 	virtual	BSize				BaseMinSize();
 	virtual	BSize				BaseMaxSize();
 	virtual	BSize				BasePreferredSize();

src/kits/interface/SplitView.cpp

@@ -180,6 +180,20 @@ BSplitView::SetCollapsible(int32 first, int32 last, bool collapsible)
 }
 
 
+bool
+BSplitView::GetItemVisible(int32 index) const
+{
+	return fSplitLayout->GetItemVisible(index);
+}
+
+
+void
+BSplitView::SetItemVisible(int32 index, bool visible)
+{
+	fSplitLayout->SetItemVisible(index, visible);
+}
+
+
 void
 BSplitView::AddChild(BView* child, BView* sibling)
 {