2 files changed, 11 insertions, 9 deletions

diff --git a/src/UI/Window.cpp b/src/UI/Window.cpp
index 8bbc4f482..cf02c0f00 100644
--- a/src/UI/Window.cpp
+++ b/src/UI/Window.cpp
@@ -362,12 +362,12 @@ void cWindow::OwnerDestroyed()
 
 
 
-bool cWindow::ForEachPlayer(cItemCallback<cPlayer> & a_Callback)
+bool cWindow::ForEachPlayer(cPlayerListCallback a_Callback)
 {
 	cCSLock Lock(m_CS);
-	for (cPlayerList::iterator itr = m_OpenedBy.begin(), end = m_OpenedBy.end(); itr != end; ++itr)
+	for (auto & Player : m_OpenedBy)
 	{
-		if (a_Callback.Item(*itr))
+		if (a_Callback(*Player))
 		{
 			return false;
 		}
@@ -379,12 +379,12 @@ bool cWindow::ForEachPlayer(cItemCallback<cPlayer> & a_Callback)
 
 
 
-bool cWindow::ForEachClient(cItemCallback<cClientHandle> & a_Callback)
+bool cWindow::ForEachClient(cClientHandleCallback a_Callback)
 {
 	cCSLock Lock(m_CS);
-	for (cPlayerList::iterator itr = m_OpenedBy.begin(), end = m_OpenedBy.end(); itr != end; ++itr)
+	for (auto & Player : m_OpenedBy)
 	{
-		if (a_Callback.Item((*itr)->GetClientHandle()))
+		if (a_Callback(*Player->GetClientHandle()))
 		{
 			return false;
 		}
diff --git a/src/UI/Window.h b/src/UI/Window.h
index d7a29dc47..bdd489d32 100644
--- a/src/UI/Window.h
+++ b/src/UI/Window.h
@@ -9,6 +9,7 @@
 
 #pragma once
 
+#include "../FunctionRef.h"
 #include "../ItemGrid.h"
 
 
@@ -31,7 +32,8 @@ class cWorld;
 
 typedef std::list<cPlayer *> cPlayerList;
 typedef std::vector<cSlotArea *> cSlotAreas;
-
+using cPlayerListCallback   = cFunctionRef<bool(cPlayer       &)>;
+using cClientHandleCallback = cFunctionRef<bool(cClientHandle &)>;
 
 
 
@@ -151,10 +153,10 @@ public:
 	void OwnerDestroyed(void);
 
 	/** Calls the callback safely for each player that has this window open; returns true if all players have been enumerated */
-	bool ForEachPlayer(cItemCallback<cPlayer> & a_Callback);
+	bool ForEachPlayer(cPlayerListCallback a_Callback);
 
 	/** Calls the callback safely for each client that has this window open; returns true if all clients have been enumerated */
-	bool ForEachClient(cItemCallback<cClientHandle> & a_Callback);
+	bool ForEachClient(cClientHandleCallback a_Callback);
 
 	/** Called on shift-clicking to distribute the stack into other areas; Modifies a_ItemStack as it is distributed!
 	if a_ShouldApply is true, the changes are written into the slots;