Replace dynamic uses of on_trait_change with observe part 2

enable/abstract_window.py

@@ -204,8 +204,8 @@ def __init__(self, **traits):
 
     def _component_changed(self, old, new):
         if old is not None:
-            old.on_trait_change(
-                self.component_bounds_changed, "bounds", remove=True
+            old.observe(
+                self.component_bounds_updated, "bounds", remove=True
             )
             old.window = None
 
@@ -218,28 +218,28 @@ def _component_changed(self, old, new):
         # If possible, size the new component according to the size of the
         # toolkit control
         size = self._get_control_size()
-        if (size is not None) and hasattr(self.component, "bounds"):
-            new.on_trait_change(self.component_bounds_changed, "bounds")
-            pix_scale = self.base_pixel_scale
-            if getattr(self.component, "fit_window", False):
-                self.component.outer_position = [0, 0]
-                self.component.outer_bounds = [
-                    size[0] / pix_scale, size[1] / pix_scale
-                ]
-            elif hasattr(self.component, "resizable"):
-                if "h" in self.component.resizable:
-                    self.component.outer_x = 0
-                    self.component.outer_width = size[0] / pix_scale
-                if "v" in self.component.resizable:
-                    self.component.outer_y = 0
-                    self.component.outer_height = size[1] / pix_scale
+        if new is not None:
+            new.observe(self.component_bounds_updated, "bounds")
+            if size is not None:
+                pix_scale = self.base_pixel_scale
+                if getattr(self.component, "fit_window", False):
+                    self.component.outer_position = [0, 0]
+                    self.component.outer_bounds = [
+                        size[0] / pix_scale, size[1] / pix_scale
+                    ]
+                elif hasattr(self.component, "resizable"):
+                    if "h" in self.component.resizable:
+                        self.component.outer_x = 0
+                        self.component.outer_width = size[0] / pix_scale
+                    if "v" in self.component.resizable:
+                        self.component.outer_y = 0
+                        self.component.outer_height = size[1] / pix_scale
         self._update_region = None
         self.redraw()
 
-    def component_bounds_changed(self, bounds):
+    def component_bounds_updated(self, event):
         """
-        Dynamic trait listener that handles our component changing its size;
-        bounds is a length-2 list of [width, height].
+        Dynamic trait listener that handles our component changing its size.
         """
         self.invalidate_draw()
         pass

enable/drawing/drawing_canvas.py

@@ -159,18 +159,14 @@ def add_button(self, *buttons):
 
     def _canvas_changed(self, old, new):
         if old:
-            old.on_trait_change(
-                self._canvas_bounds_changed, "bounds", remove=True
-            )
-            old.on_trait_change(
-                self._canvas_bounds_changed, "bounds_items", remove=True
+            old.observe(
+                self._canvas_bounds_updated, "bounds.items", remove=True
             )
 
         if new:
-            new.on_trait_change(self._canvas_bounds_changed, "bounds")
-            new.on_trait_change(self._canvas_bounds_changed, "bounds_items")
+            new.observe(self._canvas_bounds_updated, "bounds.items")
 
-    def _canvas_bounds_changed(self):
+    def _canvas_bounds_updated(self, event):
         self.width = self.canvas.width
         self.y = self.canvas.height - self.height
 

enable/examples/demo/enable/compass_example.py

@@ -18,11 +18,11 @@ def _create_component(self):
         container = OverlayContainer()
         container.add(compass)
 
-        compass.on_trait_change(self._arrow_printer, "clicked")
+        compass.observe(self._arrow_printer, "clicked")
         self.compass = compass
         return container
 
-    def _arrow_printer(self):
+    def _arrow_printer(self, event):
         print("Clicked:", self.compass.clicked)
 
 

enable/examples/demo/enable/scrollbar_demo.py

@@ -31,7 +31,7 @@ def _create_component(self):
             range=(0, 100.0, 10.0, 1.0),
             enabled=True,
         )
-        vscroll.on_trait_change(self._update_vscroll, "scroll_position")
+        vscroll.observe(self._update_vscroll, "scroll_position")
 
         hscroll = NativeScrollBar(
             orientation="horizontal",
@@ -40,31 +40,30 @@ def _create_component(self):
             range=(0, 100.0, 10.0, 1.0),
             enabled=True,
         )
-        hscroll.on_trait_change(self._update_hscroll, "scroll_position")
+        hscroll.observe(self._update_hscroll, "scroll_position")
 
         container = Container(
             bounds=[200, 200], border_visible=True, padding=15
         )
         container.add(label, hscroll, vscroll)
-        container.on_trait_change(self._update_layout, "bounds")
-        container.on_trait_change(self._update_layout, "bounds_items")
+        container.observe(self._update_layout, "bounds.items")
 
         self.label = label
         self.hscroll = hscroll
         self.vscroll = vscroll
         return container
 
-    def _update_hscroll(self):
+    def _update_hscroll(self, event):
         text = self.label.text.split("\n")
         text[0] = "h: " + str(self.hscroll.scroll_position)
         self.label.text = "\n".join(text)
 
-    def _update_vscroll(self):
+    def _update_vscroll(self, event):
         text = self.label.text.split("\n")
         text[1] = "v: " + str(self.vscroll.scroll_position)
         self.label.text = "\n".join(text)
 
-    def _update_layout(self):
+    def _update_layout(self, event):
         self.vscroll._widget_moved = True
         self.hscroll._widget_moved = True
 

enable/examples/demo/enable/slider_example.py

@@ -29,11 +29,11 @@ def _create_component(self):
         container = OverlayContainer()
         container.add(slider)
 
-        slider.on_trait_change(self.val_changed, "value")
+        slider.observe(self.val_changed, "value")
         self.slider = slider
         return container
 
-    def val_changed(self):
+    def val_changed(self, event):
         print(self.slider.value)
 
 

enable/examples/demo/enable/tools/button_tool.py

@@ -29,7 +29,8 @@ class SelectableBox(Box):
 
     selected_color = ColorTrait("green")
 
-    def select(self, selected):
+    def select(self, event):
+        selected = event.new
         self.selected = selected
 
     def _selected_changed(self):
@@ -68,7 +69,7 @@ class MyFrame(DemoFrame):
 
     """
 
-    def button_clicked(self):
+    def button_clicked(self, event):
         print("clicked")
 
     # -------------------------------------------------------------------------
@@ -86,8 +87,8 @@ def _create_component(self):
         push_button_box.tools.append(push_button_tool)
 
         # print when box clicked, change color when button down
-        push_button_tool.on_trait_change(self.button_clicked, "clicked")
-        push_button_tool.on_trait_change(push_button_box.select, "down")
+        push_button_tool.observe(self.button_clicked, "clicked")
+        push_button_tool.observe(push_button_box.select, "down")
 
         # another box for a toggle button
         toggle_box = SelectableBox(
@@ -102,7 +103,7 @@ def _create_component(self):
         toggle_box.tools.append(toggle_button_tool)
 
         # change color when checked down
-        toggle_button_tool.on_trait_change(toggle_box.select, "checked")
+        toggle_button_tool.observe(toggle_box.select, "checked")
 
         container = Container(bounds=[600, 600])
         container.add(push_button_box)

enable/tests/test_abstract_window.py

@@ -0,0 +1,41 @@
+# (C) Copyright 2005-2021 Enthought, Inc., Austin, TX
+# All rights reserved.
+#
+# This software is provided without warranty under the terms of the BSD
+# license included in LICENSE.txt and may be redistributed only under
+# the conditions described in the aforementioned license. The license
+# is also available online at http://www.enthought.com/licenses/BSD.txt
+#
+# Thanks for using Enthought open source!
+import unittest
+from unittest import mock
+
+from enable.abstract_window import AbstractWindow
+from enable.component import Component
+
+
+class TestAbstractWindow(unittest.TestCase):
+
+    @mock.patch.object(AbstractWindow, "component_bounds_updated")
+    def test_component_bounds_updated(self, mock_method):
+        """ Make sure trait listener for changing component bounds gets set up.
+        """
+
+        class TestWindow(AbstractWindow):
+            # needed to avoid a NotImplementedError, not under test
+            def _redraw(self):
+                pass
+
+            def _get_control_size(self):
+                # this happens in the wild 
+                return None
+
+        thing = Component()
+
+        TestWindow(
+            parent=None,
+            component=thing,
+        )
+        thing.bounds = [13.0, 13.0]
+
+        self.assertTrue(mock_method.called)

enable/text_field.py

@@ -460,13 +460,16 @@ def _refresh_viewed_line(self, line):
     def _acquire_focus(self, window):
         self._draw_cursor = True
         window.focus_owner = self
-        window.on_trait_change(self._focus_owner_changed, "focus_owner")
+        window.observe(self._window_focus_owner_updated, "focus_owner")
         self.request_redraw()
 
-    def _focus_owner_changed(self, obj, name, old, new):
+    def _window_focus_owner_updated(self, event):
+        obj = event.object
+        old = event.old
+        new = event.new
         if old == self and new != self:
-            obj.on_trait_change(
-                self._focus_owner_changed, "focus_owner", remove=True
+            obj.observe(
+                self._window_focus_owner_updated, "focus_owner", remove=True
             )
         self._draw_cursor = False
         self.request_redraw()

enable/trait_defs/ui/wx/enable_rgba_color_editor.py

@@ -150,8 +150,8 @@ def init(self, parent):
         self.control = window.control
         self._picker = picker
         self.control.SetSize((picker.min_width, picker.min_height))
-        picker.on_trait_change(self.popup_editor, "clicked", dispatch="ui")
-        picker.on_trait_change(self.update_object, "color", dispatch="ui")
+        picker.observe(self.popup_editor, "clicked", dispatch="ui")
+        picker.observe(self.update_object, "color", dispatch="ui")
 
     # -------------------------------------------------------------------------
     #  Invokes the pop-up editor for an object trait:

enable/trait_defs/ui/wx/rgba_color_editor.py

@@ -184,7 +184,7 @@ def init(self, parent):
         self._swatch = window.component
         self.control = window.control
         self.control.SetSize((110, 20))
-        window.component.on_trait_change(
+        window.component.observe(
             self.popup_editor, "left_up", dispatch="ui"
         )