From f777b0dd05e6af4e72be202456f6c017ac0475db Mon Sep 17 00:00:00 2001
From: Patrick Stephen <patrick.d.stephen@gmail.com>
Date: Sat, 9 Oct 2021 11:03:24 -0500
Subject: [PATCH] event: split SetCallerMap into its own interface for
 backwards compatibility

---
 event/handler.go | 3 +++
 sceneLoop.go     | 4 +++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/event/handler.go b/event/handler.go
index 8c650edb..89624e7e 100644
--- a/event/handler.go
+++ b/event/handler.go
@@ -38,7 +38,10 @@ type Handler interface {
 	UnbindAll(Event)
 	UnbindAllAndRebind(Event, []Bindable, CID, []string)
 	UnbindBindable(UnbindOption)
+}
 
+// A CallerMapper has an internal caller map that can be set.
+type CallerMapper interface {
 	SetCallerMap(*CallerMap)
 }
 
diff --git a/sceneLoop.go b/sceneLoop.go
index 15f62a34..e4a31e8c 100644
--- a/sceneLoop.go
+++ b/sceneLoop.go
@@ -130,7 +130,9 @@ func (w *Window) sceneLoop(first string, trackingInputs bool) {
 		} else {
 			w.CallerMap = event.NewCallerMap()
 		}
-		w.eventHandler.SetCallerMap(w.CallerMap)
+		if cmr, ok := w.eventHandler.(event.CallerMapper); ok {
+			cmr.SetCallerMap(w.CallerMap)
+		}
 		w.DrawStack.Clear()
 		w.DrawStack.PreDraw()