Fix error from new textualize from dismiss() in call_after_refresh.

datashuttle/tui/screens/modal_dialogs.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Optional
+from typing import TYPE_CHECKING, Callable, Optional
 
 if TYPE_CHECKING:
     from pathlib import Path
@@ -72,9 +72,10 @@ class FinishTransferScreen(ModalScreen):
     taking user input ('OK' or 'Cancel').
     """
 
-    def __init__(self, message: str) -> None:
+    def __init__(self, message: str, transfer_func: Callable) -> None:
         super().__init__()
 
+        self.transfer_func = transfer_func
         self.message = message
 
     def compose(self) -> ComposeResult:
@@ -90,15 +91,15 @@ def compose(self) -> ComposeResult:
 
     def on_button_pressed(self, event: Button.Pressed) -> None:
         if event.button.id == "confirm_ok_button":
-            # Update the display to 'transferring' before TUI freezes
-            # during data transfer.
+            # Update the display to 'transferring' before
+            # TUI freezes during data transfer.
             self.query_one("#confirm_button_container").visible = False
             self.query_one("#confirm_message_label").update("Transferring...")
             self.query_one("#confirm_message_label").call_after_refresh(
-                lambda: self.dismiss(True)
+                lambda: self.transfer_func(True)
             )
         else:
-            self.dismiss(False)
+            self.transfer_func(False)
 
 
 class SelectDirectoryTreeScreen(ModalScreen):

datashuttle/tui/tabs/transfer.py

@@ -85,6 +85,7 @@ def __init__(
         self.show_legend = self.mainwindow.load_global_settings()[
             "show_transfer_tree_status"
         ]
+        self.finish_transfer_screen: Optional[FinishTransferScreen] = None
 
     # Setup
     # ----------------------------------------------------------------------------------
@@ -277,8 +278,22 @@ def on_button_pressed(self, event: Button.Pressed) -> None:
         to confirm that the user wishes to transfer their data
         (in the direction selected). If "Yes" is selected,
         `self.transfer_data` (see below) is run.
-        """
 
+        Notes
+        -----
+        The way that Textualize works makes it difficult (impossible?)
+        to render a screen but keep the main loop with another screen.
+        What we want to do is 1) select 'OK' to start transfer
+        2) show 'Transferring...' 3) transfer data 4) tear down 'transferring'
+        screen 5) show confirmation screen. This is not simple if we want to
+        manage the actual transfer in this screen, which makes a lot of
+        sense as all options are held here The alternative is to pass all settings
+        to a `Transferring` modal dialog which seems even more convoluted. So,
+        `FinishTransferScreen` calls back to `self.transfer_data`. If 'OK' was
+        selected, the message is changed to 'Transferring'. Then, `self.transfer_data`
+        handles data transfer, teardown of the `FinishTransferScreen`
+        and display of the confirmation screen.
+        """
         if event.button.id == "transfer_transfer_button":
             if not self.query_one("#transfer_switch").value:
                 direction = "upload"
@@ -294,9 +309,15 @@ def on_button_pressed(self, event: Button.Pressed) -> None:
                 " central filesystem.\n\nAre you sure you wish to proceed?\n",
             )
 
-            self.mainwindow.push_screen(
-                FinishTransferScreen(message), self.transfer_data
+            # This is very convoluted. See docstring for details.
+            assert (
+                self.finish_transfer_screen is None
+            ), "`finish_transfer_screen` should de cleaned up in `transfer_data`."
+
+            self.finish_transfer_screen = FinishTransferScreen(
+                message, self.transfer_data
             )
+            self.mainwindow.push_screen(self.finish_transfer_screen)
 
     def on_custom_directory_tree_directory_tree_special_key_press(
         self, event: CustomDirectoryTree.DirectoryTreeSpecialKeyPress
@@ -337,6 +358,12 @@ def transfer_data(self, transfer_bool: bool) -> None:
             transfer by clicking "Yes".
 
         """
+        # Teardown the screen first, whatever `transfer_bool` is.
+        # It will not be updated until the transfer is complete.
+        assert self.finish_transfer_screen is not None
+        self.finish_transfer_screen.dismiss()
+        self.finish_transfer_screen = None
+
         if transfer_bool:
             upload = not self.query_one("#transfer_switch").value
 

tests/tests_tui/test_tui_settings.py

@@ -77,7 +77,7 @@ async def test_show_transfer_tree_status(self, setup_project_paths):
             with pytest.raises(BaseException) as e:
                 transfer_tab.query_one("#transfer_legend")
 
-            assert "No nodes match <DOMQuery query" in str(e)
+            assert "No nodes match" in str(e)
             await pilot.pause()
 
             # Go to the settings page and turn on transfer tree styling.