From 629b350a71c10b7675a70226d0ead657258f5cb6 Mon Sep 17 00:00:00 2001
From: frosch <frosch@openttd.org>
Date: Thu, 12 Aug 2010 06:40:28 +0000
Subject: [PATCH] (svn r20451) -Codechange: Add helper function
 Window::GetScrollbar() to get the Scrollbar belonging to a scrollbar widget.

---
 src/window.cpp   | 33 +++++++++++++++++++++++++++++++++
 src/window_gui.h |  2 ++
 2 files changed, 35 insertions(+)

diff --git a/src/window.cpp b/src/window.cpp
index 3081bc2688..a002de09b3 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -130,6 +130,39 @@ void Scrollbar::SetCapacityFromWidget(Window *w, int widget, int padding)
 	}
 }
 
+/**
+ * Return the Scrollbar to a widget index.
+ * @param widnum Scrollbar widget index
+ * @return Scrollbar to the widget
+ */
+const Scrollbar *Window::GetScrollbar(uint widnum) const
+{
+	const NWidgetLeaf *wid = this->GetWidget<NWidgetLeaf>(widnum);
+	switch (wid->type) {
+		case WWT_HSCROLLBAR: return &this->hscroll;
+		case WWT_SCROLLBAR:  return &this->vscroll;
+		case WWT_SCROLL2BAR: return &this->vscroll2;
+		default: NOT_REACHED();
+	}
+}
+
+/**
+ * Return the Scrollbar to a widget index.
+ * @param widnum Scrollbar widget index
+ * @return Scrollbar to the widget
+ */
+Scrollbar *Window::GetScrollbar(uint widnum)
+{
+	NWidgetLeaf *wid = this->GetWidget<NWidgetLeaf>(widnum);
+	switch (wid->type) {
+		case WWT_HSCROLLBAR: return &this->hscroll;
+		case WWT_SCROLLBAR:  return &this->vscroll;
+		case WWT_SCROLL2BAR: return &this->vscroll2;
+		default: NOT_REACHED();
+	}
+}
+
+
 /**
  * Set the window that has the focus
  * @param w The window to set the focus on
diff --git a/src/window_gui.h b/src/window_gui.h
index 38a8759d7e..13f61d6289 100644
--- a/src/window_gui.h
+++ b/src/window_gui.h
@@ -407,6 +407,8 @@ public:
 	template <class NWID>
 	inline NWID *GetWidget(uint widnum);
 
+	const Scrollbar *GetScrollbar(uint widnum) const;
+	Scrollbar *GetScrollbar(uint widnum);
 
 	void InitNested(const WindowDesc *desc, WindowNumber number = 0);
 	void CreateNestedTree(const WindowDesc *desc, bool fill_nested = true);