hook up progress-bar, uri display

the road to callback hell is plagued with good intentions:
I am not unwilling to revisit this code if it gets any more gnarly

buffer.fnl

@@ -2,6 +2,7 @@
 (local { : view } (require :fennel))
 
 (fn new-buffer [name]
+  (var property-change-listener nil)
   (let [props {}
         widget (WebKit2.WebView {
                                  ;; :on_decide_policy
@@ -19,11 +20,16 @@
                                     (when (not (= pspec.name :parent))
                                       (let [val (. self pspec.name)]
                                         (tset props pspec.name val)
-                                        ;(listeners:notify pspec.name val)
+                                        (when property-change-listener
-                                        )))
+                                          (property-change-listener
+                                           pspec.name val)))
+                                        ))
                                  })]
     {:webview widget
      :name name
+     :subscribe-property-changes
+     (fn [self cb]
+       (set property-change-listener cb))
      :location #(widget:get_uri)
      :visit (fn [_ u] (widget:load_uri u))
      :properties props}))

command.fnl

@@ -183,6 +183,9 @@
               :widget box
               : prompt
               : frame
+              :set-inactive-text (fn [self text]
+                                   (when (not self.state.active)
+                                     (tset entry :text text)))
               :completions-widget completions
               }]
     (hbox:pack_start prompt false false 15)

frame.fnl

@@ -30,7 +30,14 @@
         contentwidget (Gtk.Box {
                                 :orientation Gtk.Orientation.VERTICAL
                                 })
-        ]
+        update-prop (fn [name value]
+                      (match name
+                        :estimated-load-progress
+                        (tset progress-bar :fraction value)
+                        :uri
+                        (commander:set-inactive-text value)
+                        n
+                        (comment (print "prop change" n value))))]
 
     (tset window :on_key_release_event
           (fn [window event]
@@ -58,6 +65,11 @@
                             (w:hide))
                           (tset self :buffer b)
                           (contentwidget:pack_start b.webview true true 0)
+                          (b:subscribe-property-changes
+                           (fn [name val]
+                             (if (= b self.buffer)
+                                 (update-prop name val)
+                                 (print "ignore props from background" b))))
                           (b.webview:show))
            }]
       (lume.extend self f)