✨ Add an example for Textualize/textual#3472

work_from_work.py

@@ -0,0 +1,47 @@
+"""Example for https://github.com/Textualize/textual/issues/3472"""
+
+from time import sleep
+
+from textual import on, work
+from textual.app import App, ComposeResult
+from textual.widgets import Button, Log
+from textual.worker import get_current_worker
+
+class WorkerInWorkerApp(App[None]):
+
+    def compose(self) -> ComposeResult:
+        yield Button("Start")
+        yield Log()
+
+    @work(thread=True)
+    def outer(self) -> None:
+        worker = get_current_worker()
+        for n in range(50):
+            if worker.is_cancelled:
+                break
+            if n == 10:
+                self.call_from_thread(self.inner)
+            self.call_from_thread(
+                self.query_one(Log).write_line,
+                f"Outer {n}"
+            )
+            sleep(0.25)
+
+    @work(thread=True)
+    def inner(self) -> None:
+        worker = get_current_worker()
+        for n in range(50):
+            if worker.is_cancelled:
+                break
+            self.call_from_thread(
+                self.query_one(Log).write_line,
+                f"Inner {n}"
+            )
+            sleep(0.25)
+
+    @on(Button.Pressed)
+    def start(self) -> None:
+        self.outer()
+
+if __name__ == "__main__":
+    WorkerInWorkerApp().run()