Connect up the Qt bridge in the viewer

src/calibre/gui2/viewer2/ui.py

@@ -70,3 +70,4 @@ class EbookViewer(MainWindow):
                 det_msg=data['tb'], show=True)
             return
         set_book_path(data['base'])
+        self.web_view.start_book_load()

src/calibre/gui2/viewer2/web_view.py

@@ -122,14 +122,9 @@ def create_profile():
 
 class ViewerBridge(Bridge):
 
-    request_sync = from_js(object, object, object)
-    request_split = from_js(object, object)
     live_css_data = from_js(object)
 
-    go_to_sourceline_address = to_js()
-    go_to_anchor = to_js()
-    set_split_mode = to_js()
-    live_css = to_js()
+    start_book_load = to_js()
 
 
 class WebPage(QWebEnginePage):
@@ -169,6 +164,8 @@ class WebView(RestartingWebEngineView):
         w = QApplication.instance().desktop().availableGeometry(self).width()
         self._size_hint = QSize(int(w/3), int(w/2))
         self._page = WebPage(self)
+        self.bridge.bridge_ready.connect(self.on_bridge_ready)
+        self.pending_bridge_ready_actions = set()
         self.setPage(self._page)
         self.setAcceptDrops(False)
         self.clear()
@@ -189,3 +186,17 @@ class WebView(RestartingWebEngineView):
 
     def clear(self):
         self.setHtml('<p>&nbsp;', QUrl('{}://{}/'.format(FAKE_PROTOCOL, FAKE_HOST)))
+
+    @property
+    def bridge(self):
+        return self._page.bridge
+
+    def on_bridge_ready(self):
+        for func, args in self.pending_bridge_ready_actions:
+            getattr(self.bridge, func)(*args)
+
+    def start_book_load(self):
+        if self.bridge.ready:
+            self.bridge.start_book_load()
+        else:
+            self.pending_bridge_ready_actions.add(('start_book_load', ()))

src/calibre/gui2/webengine.py

@@ -73,6 +73,8 @@ class to_js_bound(QObject):
 
 class Bridge(QObject):
 
+    bridge_ready = pyqtSignal()
+
     def __init__(self, page):
         QObject.__init__(self, page)
         self._signals = json.dumps(tuple({k for k, v in self.__class__.__dict__.iteritems() if isinstance(v, pyqtSignal)}))
@@ -100,6 +102,7 @@ class Bridge(QObject):
             if isinstance(v, to_js):
                 setattr(self, k, to_js_bound(self, k))
         self.page.runJavaScript('python_comm._register_signals(' + self._signals + ')', QWebEngineScript.ApplicationWorld)
+        self.bridge_ready.emit()
 
     def _poll_for_messages(self):
         self.page.runJavaScript('python_comm._poll()', QWebEngineScript.ApplicationWorld, self._dispatch_messages)

src/pyj/viewer-main.pyj

@@ -5,6 +5,7 @@ from __python__ import bound_methods, hash_literals
 
 from elementmaker import E
 from read_book.globals import runtime, ui_operations
+from qt import from_python
 
 def container_div(id):
     return E.div(id=id, style='margin: 0; padding: 0; display: none')
@@ -28,13 +29,19 @@ def show_error(title, msg, details):
     pass  # TODO: Implement this
 
 
+@from_python
+def start_book_load():
+    print(111111111111111)
+
+
 if window is window.top:
     # main
-    document.body.appendChild(E.iframe(srcdoc="<p> "))
     ui_operations.get_file = get_file
     ui_operations.get_mathjax_files = get_mathjax_files
     ui_operations.update_url_state = update_url_state
     ui_operations.show_error = show_error
+    document.body.appendChild(E.div(id='loading'))
+    document.body.appendChild(E.div(id='view'))
 else:
     # iframe
     pass