14/18: gurses: Cache the windows of buttons.

[John Darrington]

jmd pushed a commit to branch wip-installer
in repository guix.

commit 89148e7694e8542a0d11e67f2fe4bcb96437e8a5
Author: John Darrington <address@hidden>
Date:   Wed Feb 1 16:20:48 2017 +0100

    gurses: Cache the windows of buttons.
    
    * gurses/buttons.scm (<buttons>): New field: bwindows.
---
 gurses/buttons.scm |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gurses/buttons.scm b/gurses/buttons.scm
index 5afef38..a91b01f 100644
--- a/gurses/buttons.scm
+++ b/gurses/buttons.scm
@@ -35,15 +35,16 @@
   #:use-module (srfi srfi-9))
 
 (define-record-type <buttons>
-  (make-buttons' items selected active-color)
+  (make-buttons' items bwindows selected active-color)
   buttons?
   (items         buttons-items  buttons-set-items!) ;; FIXME this need not be 
here
+  (bwindows      buttons-bwindows buttons-set-bwindows!)
   (selected      buttons-selected buttons-set-selected!)
   (array         buttons-array  buttons-set-array!)
   (active-color  buttons-active-color))
 
 (define (make-buttons items color)
-  (make-buttons' items  -1 color))
+  (make-buttons' items '()  -1 color))
 
 (define (buttons-n-buttons buttons)
   (array-length (buttons-array buttons)))
@@ -147,6 +148,7 @@
                      (w (derwin win 3 width 0
                                 (round (- (* (1+ i) (/ (getmaxx win) (1+ n)))
                                           (/ width 2))) #:panel #f)))
+                (buttons-set-bwindows! buttons (cons w (buttons-bwindows 
buttons)))
                 (box w   0 0)
                 (addchstr w label #:y 1 #:x 1)
                 (loop (cdr bl) (1+ i) (acons mark (list w key) alist)))))))))