Drop explicit sender attribute from messages

CHANGELOG.md

@@ -5,6 +5,24 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [0.14.0] - Unreleased
+
+### Changes
+
+- Breaking change: There is now only `post_message` to post events, which is non-async, `post_message_no_wait` was dropped. https://github.com/Textualize/textual/pull/1940
+- Breaking change: The Timer class now has just one method to stop it, `Timer.stop` which is non sync https://github.com/Textualize/textual/pull/1940
+- Breaking change: Messages don't require a `sender` in their constructor https://github.com/Textualize/textual/pull/1940
+- Many messages have grown a `control` property which returns the control they relate to. https://github.com/Textualize/textual/pull/1940
+
+
+### Added
+
+- Added `data_table` attribute to DataTable events https://github.com/Textualize/textual/pull/1940
+- Added `list_view` attribute to `ListView` events https://github.com/Textualize/textual/pull/1940
+- Added `radio_set` attribute to `RadioSet` events https://github.com/Textualize/textual/pull/1940
+- Added `switch` attribute to `Switch` events https://github.com/Textualize/textual/pull/1940
+- Breaking change: Added `toggle_button` attribute to RadioButton and Checkbox events, replaces `input` https://github.com/Textualize/textual/pull/1940
+
 ## [0.13.0] - 2023-03-02
 
 ### Added

docs/examples/events/custom01.py

@@ -10,9 +10,9 @@ class ColorButton(Static):
     class Selected(Message):
         """Color selected message."""
 
-        def __init__(self, sender: MessageTarget, color: Color) -> None:
+        def __init__(self, color: Color) -> None:
             self.color = color
-            super().__init__(sender)
+            super().__init__()
 
     def __init__(self, color: Color) -> None:
         self.color = color
@@ -24,9 +24,9 @@ def on_mount(self) -> None:
         self.styles.background = Color.parse("#ffffff33")
         self.styles.border = ("tall", self.color)
 
-    async def on_click(self) -> None:
+    def on_click(self) -> None:
         # The post_message method sends an event to be handled in the DOM
-        await self.post_message(self.Selected(self, self.color))
+        self.post_message(self.Selected(self.color))
 
     def render(self) -> str:
         return str(self.color)

docs/guide/events.md

@@ -107,16 +107,11 @@ The message class is defined within the widget class itself. This is not strictl
 - It reduces the amount of imports. If you import `ColorButton`, you have access to the message class via `ColorButton.Selected`.
 - It creates a namespace for the handler. So rather than `on_selected`, the handler name becomes `on_color_button_selected`. This makes it less likely that your chosen name will clash with another message.
 
+### Sending messages
 
-## Sending messages
-
-In the previous example we used [post_message()][textual.message_pump.MessagePump.post_message] to send an event to its parent. We could also have used [post_message_no_wait()][textual.message_pump.MessagePump.post_message_no_wait] for non async code. Sending messages in this way allows you to write custom widgets without needing to know in what context they will be used.
-
-There are other ways of sending (posting) messages, which you may need to use less frequently.
-
-- [post_message][textual.message_pump.MessagePump.post_message] To post a message to a particular widget.
-- [post_message_no_wait][textual.message_pump.MessagePump.post_message_no_wait] The non-async version of `post_message`.
+To send a message call the [post_message()][textual.message_pump.MessagePump.post_message] method. This will place a message on the widget's message queue and run any message handlers.
 
+It is common for widgets to send messages to themselves, and allow them to bubble. This is so a base class has an opportunity to handle the message. We do this in the example above, which means a subclass could add a `on_color_button_selected` if it wanted to handle the message itself.
 
 ## Preventing messages
 

src/textual/_animator.py

@@ -182,7 +182,6 @@ def __init__(self, app: App, frames_per_second: int = 60) -> None:
         self._timer = Timer(
             app,
             1 / frames_per_second,
-            app,
             name="Animator",
             callback=self,
             pause=True,
@@ -201,7 +200,7 @@ async def start(self) -> None:
     async def stop(self) -> None:
         """Stop the animator task."""
         try:
-            await self._timer.stop()
+            self._timer.stop()
         except asyncio.CancelledError:
             pass
         finally:

src/textual/_types.py

@@ -8,21 +8,18 @@
 
 
 class MessageTarget(Protocol):
-    async def post_message(self, message: "Message") -> bool:
+    async def _post_message(self, message: "Message") -> bool:
         ...
 
-    async def _post_priority_message(self, message: "Message") -> bool:
-        ...
-
-    def post_message_no_wait(self, message: "Message") -> bool:
+    def post_message(self, message: "Message") -> bool:
         ...
 
 
 class EventTarget(Protocol):
-    async def post_message(self, message: "Message") -> bool:
+    async def _post_message(self, message: "Message") -> bool:
         ...
 
-    def post_message_no_wait(self, message: "Message") -> bool:
+    def post_message(self, message: "Message") -> bool:
         ...
 
 

src/textual/_xterm_parser.py

@@ -26,10 +26,7 @@
 class XTermParser(Parser[events.Event]):
     _re_sgr_mouse = re.compile(r"\x1b\[<(\d+);(\d+);(\d+)([Mm])")
 
-    def __init__(
-        self, sender: MessageTarget, more_data: Callable[[], bool], debug: bool = False
-    ) -> None:
-        self.sender = sender
+    def __init__(self, more_data: Callable[[], bool], debug: bool = False) -> None:
         self.more_data = more_data
         self.last_x = 0
         self.last_y = 0
@@ -47,7 +44,7 @@ def feed(self, data: str) -> Iterable[events.Event]:
         self.debug_log(f"FEED {data!r}")
         return super().feed(data)
 
-    def parse_mouse_code(self, code: str, sender: MessageTarget) -> events.Event | None:
+    def parse_mouse_code(self, code: str) -> events.Event | None:
         sgr_match = self._re_sgr_mouse.match(code)
         if sgr_match:
             _buttons, _x, _y, state = sgr_match.groups()
@@ -74,7 +71,6 @@ def parse_mouse_code(self, code: str, sender: MessageTarget) -> events.Event | N
                 button = (buttons + 1) & 3
 
             event = event_class(
-                sender,
                 x,
                 y,
                 delta_x,
@@ -103,7 +99,7 @@ def reissue_sequence_as_keys(reissue_sequence: str) -> None:
                 key_events = sequence_to_key_events(character)
                 for event in key_events:
                     if event.key == "escape":
-                        event = events.Key(event.sender, "circumflex_accent", "^")
+                        event = events.Key("circumflex_accent", "^")
                     on_token(event)
 
         while not self.is_eof:
@@ -116,9 +112,7 @@ def reissue_sequence_as_keys(reissue_sequence: str) -> None:
                 # the full escape code was.
                 pasted_text = "".join(paste_buffer[:-1])
                 # Note the removal of NUL characters: https://github.com/Textualize/textual/issues/1661
-                on_token(
-                    events.Paste(self.sender, text=pasted_text.replace("\x00", ""))
-                )
+                on_token(events.Paste(pasted_text.replace("\x00", "")))
                 paste_buffer.clear()
 
             character = ESC if use_prior_escape else (yield read1())
@@ -145,12 +139,12 @@ def reissue_sequence_as_keys(reissue_sequence: str) -> None:
                     peek_buffer = yield self.peek_buffer()
                     if not peek_buffer:
                         # An escape arrived without any following characters
-                        on_token(events.Key(self.sender, "escape", "\x1b"))
+                        on_token(events.Key("escape", "\x1b"))
                         continue
                     if peek_buffer and peek_buffer[0] == ESC:
                         # There is an escape in the buffer, so ESC ESC has arrived
                         yield read1()
-                        on_token(events.Key(self.sender, "escape", "\x1b"))
+                        on_token(events.Key("escape", "\x1b"))
                         # If there is no further data, it is not part of a sequence,
                         # So we don't need to go in to the loop
                         if len(peek_buffer) == 1 and not more_data():
@@ -208,7 +202,7 @@ def reissue_sequence_as_keys(reissue_sequence: str) -> None:
                         mouse_match = _re_mouse_event.match(sequence)
                         if mouse_match is not None:
                             mouse_code = mouse_match.group(0)
-                            event = self.parse_mouse_code(mouse_code, self.sender)
+                            event = self.parse_mouse_code(mouse_code)
                             if event:
                                 on_token(event)
                             break
@@ -221,11 +215,7 @@ def reissue_sequence_as_keys(reissue_sequence: str) -> None:
                                 mode_report_match["mode_id"] == "2026"
                                 and int(mode_report_match["setting_parameter"]) > 0
                             ):
-                                on_token(
-                                    messages.TerminalSupportsSynchronizedOutput(
-                                        self.sender
-                                    )
-                                )
+                                on_token(messages.TerminalSupportsSynchronizedOutput())
                             break
             else:
                 if not bracketed_paste:
@@ -247,9 +237,7 @@ def _sequence_to_key_events(
         keys = ANSI_SEQUENCES_KEYS.get(sequence)
         if keys is not None:
             for key in keys:
-                yield events.Key(
-                    self.sender, key.value, sequence if len(sequence) == 1 else None
-                )
+                yield events.Key(key.value, sequence if len(sequence) == 1 else None)
         elif len(sequence) == 1:
             try:
                 if not sequence.isalnum():
@@ -262,6 +250,6 @@ def _sequence_to_key_events(
                 else:
                     name = sequence
                 name = KEY_NAME_REPLACEMENTS.get(name, name)
-                yield events.Key(self.sender, name, sequence)
+                yield events.Key(name, sequence)
             except:
-                yield events.Key(self.sender, sequence, sequence)
+                yield events.Key(sequence, sequence)

src/textual/app.py

@@ -525,7 +525,7 @@ def exit(
         """
         self._exit = True
         self._return_value = result
-        self.post_message_no_wait(messages.ExitApp(sender=self))
+        self.post_message(messages.ExitApp())
         if message:
             self._exit_renderables.append(message)
 
@@ -878,7 +878,7 @@ async def _press_keys(self, keys: Iterable[str]) -> None:
                 except KeyError:
                     char = key if len(key) == 1 else None
                 print(f"press {key!r} (char={char!r})")
-                key_event = events.Key(app, key, char)
+                key_event = events.Key(key, char)
                 driver.send_event(key_event)
                 await wait_for_idle(0)
 
@@ -1272,7 +1272,7 @@ def _replace_screen(self, screen: Screen) -> Screen:
             The screen that was replaced.
 
         """
-        screen.post_message_no_wait(events.ScreenSuspend(self))
+        screen.post_message(events.ScreenSuspend())
         self.log.system(f"{screen} SUSPENDED")
         if not self.is_screen_installed(screen) and screen not in self._screen_stack:
             screen.remove()
@@ -1288,7 +1288,7 @@ def push_screen(self, screen: Screen | str) -> AwaitMount:
         """
         next_screen, await_mount = self._get_screen(screen)
         self._screen_stack.append(next_screen)
-        self.screen.post_message_no_wait(events.ScreenResume(self))
+        self.screen.post_message(events.ScreenResume())
         self.log.system(f"{self.screen} is current (PUSHED)")
         return await_mount
 
@@ -1303,7 +1303,7 @@ def switch_screen(self, screen: Screen | str) -> AwaitMount:
             self._replace_screen(self._screen_stack.pop())
             next_screen, await_mount = self._get_screen(screen)
             self._screen_stack.append(next_screen)
-            self.screen.post_message_no_wait(events.ScreenResume(self))
+            self.screen.post_message(events.ScreenResume())
             self.log.system(f"{self.screen} is current (SWITCHED)")
             return await_mount
         return AwaitMount(self.screen, [])
@@ -1382,7 +1382,7 @@ def pop_screen(self) -> Screen:
             )
         previous_screen = self._replace_screen(screen_stack.pop())
         self.screen._screen_resized(self.size)
-        self.screen.post_message_no_wait(events.ScreenResume(self))
+        self.screen.post_message(events.ScreenResume())
         self.log.system(f"{self.screen} is active")
         return previous_screen
 
@@ -1395,7 +1395,7 @@ def set_focus(self, widget: Widget | None, scroll_visible: bool = True) -> None:
         """
         self.screen.set_focus(widget, scroll_visible)
 
-    async def _set_mouse_over(self, widget: Widget | None) -> None:
+    def _set_mouse_over(self, widget: Widget | None) -> None:
         """Called when the mouse is over another widget.
 
         Args:
@@ -1404,16 +1404,16 @@ async def _set_mouse_over(self, widget: Widget | None) -> None:
         if widget is None:
             if self.mouse_over is not None:
                 try:
-                    await self.mouse_over.post_message(events.Leave(self))
+                    self.mouse_over.post_message(events.Leave())
                 finally:
                     self.mouse_over = None
         else:
             if self.mouse_over is not widget:
                 try:
                     if self.mouse_over is not None:
-                        await self.mouse_over._forward_event(events.Leave(self))
+                        self.mouse_over._forward_event(events.Leave())
                     if widget is not None:
-                        await widget._forward_event(events.Enter(self))
+                        widget._forward_event(events.Enter())
                 finally:
                     self.mouse_over = widget
 
@@ -1426,12 +1426,10 @@ def capture_mouse(self, widget: Widget | None) -> None:
         if widget == self.mouse_captured:
             return
         if self.mouse_captured is not None:
-            self.mouse_captured.post_message_no_wait(
-                events.MouseRelease(self, self.mouse_position)
-            )
+            self.mouse_captured.post_message(events.MouseRelease(self.mouse_position))
         self.mouse_captured = widget
         if widget is not None:
-            widget.post_message_no_wait(events.MouseCapture(self, self.mouse_position))
+            widget.post_message(events.MouseCapture(self.mouse_position))
 
     def panic(self, *renderables: RenderableType) -> None:
         """Exits the app then displays a message.
@@ -1544,8 +1542,8 @@ async def invoke_ready_callback() -> None:
             with self.batch_update():
                 try:
                     try:
-                        await self._dispatch_message(events.Compose(sender=self))
-                        await self._dispatch_message(events.Mount(sender=self))
+                        await self._dispatch_message(events.Compose())
+                        await self._dispatch_message(events.Mount())
                     finally:
                         self._mounted_event.set()
 
@@ -1575,11 +1573,11 @@ async def invoke_ready_callback() -> None:
                     await self.animator.stop()
                 finally:
                     for timer in list(self._timers):
-                        await timer.stop()
+                        timer.stop()
 
         self._running = True
         try:
-            load_event = events.Load(sender=self)
+            load_event = events.Load()
             await self._dispatch_message(load_event)
 
             driver: Driver
@@ -1825,7 +1823,7 @@ async def _shutdown(self) -> None:
         await self._close_all()
         await self._close_messages()
 
-        await self._dispatch_message(events.Unmount(sender=self))
+        await self._dispatch_message(events.Unmount())
 
         self._print_error_renderables()
         if self.devtools is not None and self.devtools.is_connected:
@@ -1953,19 +1951,19 @@ async def on_event(self, event: events.Event) -> None:
             if isinstance(event, events.MouseEvent):
                 # Record current mouse position on App
                 self.mouse_position = Offset(event.x, event.y)
-                await self.screen._forward_event(event)
+                self.screen._forward_event(event)
             elif isinstance(event, events.Key):
                 if not await self.check_bindings(event.key, priority=True):
                     forward_target = self.focused or self.screen
-                    await forward_target._forward_event(event)
+                    forward_target._forward_event(event)
             else:
-                await self.screen._forward_event(event)
+                self.screen._forward_event(event)
 
         elif isinstance(event, events.Paste) and not event.is_forwarded:
             if self.focused is not None:
-                await self.focused._forward_event(event)
+                self.focused._forward_event(event)
             else:
-                await self.screen._forward_event(event)
+                self.screen._forward_event(event)
         else:
             await super().on_event(event)
 
@@ -2092,7 +2090,7 @@ async def _on_shutdown_request(self, event: events.ShutdownRequest) -> None:
 
     async def _on_resize(self, event: events.Resize) -> None:
         event.stop()
-        await self.screen.post_message(event)
+        self.screen.post_message(event)
 
     def _detach_from_dom(self, widgets: list[Widget]) -> list[Widget]:
         """Detach a list of widgets from the DOM.

src/textual/dom.py

@@ -163,7 +163,7 @@ def auto_refresh(self) -> float | None:
     @auto_refresh.setter
     def auto_refresh(self, interval: float | None) -> None:
         if self._auto_refresh_timer is not None:
-            self._auto_refresh_timer.stop_no_wait()
+            self._auto_refresh_timer.stop()
             self._auto_refresh_timer = None
         if interval is not None:
             self._auto_refresh_timer = self.set_interval(