diff --git a/action.go b/action.go
index 7db5371..df634e2 100644
--- a/action.go
+++ b/action.go
@@ -54,6 +54,7 @@ const (
 	GetText
 	SetText
 	AddText
+	Checked
 	Show
 	Hide
 	Enable
diff --git a/state.go b/state.go
index bb460b4..ca0a2af 100644
--- a/state.go
+++ b/state.go
@@ -20,6 +20,9 @@ type State struct {
 	// how to arrange widgets
 	Direction Orientation
 
+	// for widgets that have on/off things
+	Checked bool
+
 	//
 	// This is complicated. We must send a list of all the widgets
 	// in the binary tree to the toolkits because some toolkits