Hide mouse help after presentation is ungrafted

TODO.FACTOR.txt

@@ -29,7 +29,6 @@
     space
 - we have trouble drawing rectangles
 - UI dataflow visualizer
-- status help persists after clicking on a link
 - tool help
 - browser: show currently selected vocab & words
 - doc sweep

library/ui/gadgets/presentations.factor

@@ -36,6 +36,9 @@ C: presentation ( button object commands -- button )
 : hide-mouse-help ( presentation -- )
     find-world [ world-status f swap set-model* ] when* ;
 
+M: presentation ungraft* ( presentation -- )
+    dup hide-mouse-help delegate ungraft* ;
+
 presentation H{
     { T{ button-up f f 1 } [ [ 1 invoke-presentation ] if-clicked ] }
     { T{ button-up f f 2 } [ [ 2 invoke-presentation ] if-clicked ] }

library/ui/gestures.factor

@@ -64,6 +64,7 @@ TUPLE: key-up mods sym ;
 ! are in the co-ordinate system of the world which contains
 ! the gadget in question.
 SYMBOL: hand-gadget
+SYMBOL: hand-world
 SYMBOL: hand-loc
 { 0 0 } hand-loc set-global
 
@@ -146,6 +147,7 @@ V{ } clone hand-buttons set-global
     hand-gadget get-global parents <reversed> ;
 
 : move-hand ( loc world -- )
+    dup hand-world set-global
     under-hand >r over hand-loc set-global
     pick-up hand-gadget set-global
     under-hand r> hand-gestures ;

library/ui/ui.factor

@@ -28,7 +28,7 @@ SYMBOL: windows
 
 : update-hand ( gadget -- )
     find-world [
-        dup hand-gadget get-global find-world eq?
+        dup hand-world get-global eq?
         [ hand-loc get-global swap move-hand ] [ drop ] if
     ] when* ;