Ignore old view generation errors

hexrdgui/async_worker.py

@@ -50,12 +50,13 @@ class AsyncWorker(QRunnable):
     '''
 
     def __init__(self, fn, *args, **kwargs):
-        super(AsyncWorker, self).__init__()
+        super().__init__()
         # Store constructor arguments (re-used for processing)
         self.fn = fn
         self.args = args
         self.kwargs = kwargs
         self.signals = AsyncWorkerSignals()
+        self.print_error_traceback = True
 
         # If the function signature accepts an 'update_progress'
         # function, set it to emit the progress signal.
@@ -72,7 +73,9 @@ def run(self):
         try:
             result = self.fn(*self.args, **self.kwargs)
         except:
-            traceback.print_exc()
+            if self.print_error_traceback:
+                traceback.print_exc()
+
             exctype, value = sys.exc_info()[:2]
             self.signals.error.emit((exctype, value, traceback.format_exc()))
         else:

hexrdgui/image_canvas.py

@@ -1,6 +1,7 @@
 import copy
 import math
 import logging
+import sys
 
 from PySide6.QtCore import QThreadPool, QTimer, Signal, Qt
 from PySide6.QtWidgets import QFileDialog, QMessageBox
@@ -72,6 +73,7 @@ def __init__(self, parent=None, image_names=None):
         self.blit_manager = BlitManager(self)
         self.raw_view_images_dict = {}
         self._mask_boundary_artists = []
+        self._latest_compute_view_worker = None
 
         # Track the current mode so that we can more lazily clear on change.
         self.mode = None
@@ -973,13 +975,21 @@ def show_cartesian(self):
 
         # Run the view generation in a background thread
         worker = AsyncWorker(cartesian_viewer)
+        worker.print_error_traceback = False
+        worker.signals._image_mode = self.mode
         self.thread_pool.start(worker)
+        self._latest_compute_view_worker = worker
 
         # Get the results and close the progress dialog when finished
         worker.signals.result.connect(self.finish_show_cartesian)
         worker.signals.error.connect(self.async_worker_error)
 
     def finish_show_cartesian(self, iviewer):
+        if self.sender() is not self._latest_compute_view_worker.signals:
+            # A new calculation must have been started while this was running.
+            # Forget this one...
+            return
+
         if self.mode != ViewType.cartesian:
             # Image mode was switched during generation. Ignore this.
             return
@@ -1040,13 +1050,20 @@ def show_polar(self):
 
         # Run the view generation in a background thread
         worker = AsyncWorker(polar_viewer)
+        worker.print_error_traceback = False
+        worker.signals._image_mode = self.mode
         self.thread_pool.start(worker)
+        self._latest_compute_view_worker = worker
 
         # Get the results and close the progress dialog when finished
         worker.signals.result.connect(self.finish_show_polar)
         worker.signals.error.connect(self.async_worker_error)
 
     def finish_show_polar(self, iviewer):
+        if self.sender() is not self._latest_compute_view_worker.signals:
+            # A new calculation must have been started while this was running.
+            # Forget this one...
+            return
 
         if self.mode != ViewType.polar:
             # Image mode was switched during generation. Ignore this.
@@ -1219,13 +1236,21 @@ def show_stereo(self):
 
         # Run the view generation in a background thread
         worker = AsyncWorker(stereo_viewer)
+        worker.print_error_traceback = False
+        worker.signals._image_mode = self.mode
         self.thread_pool.start(worker)
+        self._latest_compute_view_worker = worker
 
         # Get the results and close the progress dialog when finished
         worker.signals.result.connect(self.finish_show_stereo)
         worker.signals.error.connect(self.async_worker_error)
 
     def finish_show_stereo(self, iviewer):
+        if self.sender() is not self._latest_compute_view_worker.signals:
+            # A new calculation must have been started while this was running.
+            # Forget this one...
+            return
+
         if self.mode != ViewType.stereo:
             # Image mode was switched during generation. Ignore this.
             return
@@ -1390,6 +1415,19 @@ def polar_masks_changed(self):
         HexrdConfig().polar_masks_reapplied.emit(img)
 
     def async_worker_error(self, error):
+        if self.sender() is not self._latest_compute_view_worker.signals:
+            # A new calculation must have been started while this was running.
+            # This error doesn't matter anymore...
+            return
+
+        if self.sender()._image_mode != self.mode:
+            # We changed modes while this was running, and it doesn't matter
+            # anymore...
+            return
+
+        # We disabled traceback printing in the async worker, so print it
+        # now.
+        print(error[2], file=sys.stderr)
         QMessageBox.critical(self, 'HEXRD', str(error[1]))
         msg = f'{str(self.mode)} view error!'
         HexrdConfig().emit_update_status_bar(msg)