js transformer enhanced and focus method added in wv-element

wv-element.rkt

@@ -2,6 +2,7 @@
 
 (require racket/class
          "racket-webview.rkt"
+         "private/js-transform.rkt"
          )
 
 (provide wv-element%)
@@ -87,6 +88,13 @@
     (define/public (attr/datetime attr)
       (webview-attr/datetime wv element-id attr))
 
+    (define/public (focus!)
+      (let ((s (js (let* ((el (send document getElementById (eval element-id))))
+                     (if (=== el null)
+                         (console.log (+ "Element " (eval element-id) " not found"))
+                         (send el focus))))))
+        (webview-run-js wv s)))
+
     (super-new)
     )
   )