refactor: ui: Store Frame as a View attribute.

This commit stores the Fame widget of View as an attribute so that
it can be easily manipulated for various purposes like overlaying
widgets , adding padding, etc.

Tests added.

Author: Rohitth007

tests/ui/test_ui.py

@@ -82,15 +82,15 @@ def test_set_footer_text_default(self, view: View, mocker: MockerFixture) -> Non
 
         view.set_footer_text()
 
-        view._w.footer.set_text.assert_called_once_with(["some help text"])
+        view.frame.footer.set_text.assert_called_once_with(["some help text"])
         view.controller.update_screen.assert_called_once_with()
 
     def test_set_footer_text_specific_text(
         self, view: View, text: str = "blah"
     ) -> None:
         view.set_footer_text([text])
 
-        view._w.footer.set_text.assert_called_once_with([text])
+        view.frame.footer.set_text.assert_called_once_with([text])
         view.controller.update_screen.assert_called_once_with()
 
     def test_set_footer_text_with_duration(
@@ -105,7 +105,7 @@ def test_set_footer_text_with_duration(
 
         view.set_footer_text([custom_text], duration=duration)
 
-        view._w.footer.set_text.assert_has_calls(
+        view.frame.footer.set_text.assert_has_calls(
             [mocker.call([custom_text]), mocker.call(["some help text"])]
         )
         mock_sleep.assert_called_once_with(duration)
@@ -226,6 +226,7 @@ def just_set_message_view(self: Any) -> None:
         frame.assert_called_once_with(
             view.body, col(), focus_part="body", footer=footer_view()
         )
+        assert view.frame == frame()
         show_left_panel.assert_called_once_with(visible=True)
 
     @pytest.mark.parametrize("autohide", [True, False])

zulipterminal/ui.py

@@ -107,8 +107,8 @@ def set_footer_text(
             text = self.get_random_help()
         else:
             text = text_list
-        self._w.footer.set_text(text)
-        self._w.footer.set_attr_map({None: style})
+        self.frame.footer.set_text(text)
+        self.frame.footer.set_attr_map({None: style})
         self.controller.update_screen()
         if duration is not None:
             assert duration > 0
@@ -177,14 +177,14 @@ def main_window(self) -> Any:
             ]
         )
 
-        w = urwid.Frame(
+        self.frame = urwid.Frame(
             self.body, title_bar, focus_part="body", footer=self.footer_view()
         )
 
         # Show left panel on startup in autohide mode
         self.show_left_panel(visible=True)
 
-        return w
+        return self.frame
 
     def show_left_panel(self, *, visible: bool) -> None:
         if not self.controller.autohide: