From 95295e1f6198ba6b7ade053ece91fbb58a5493b4 Mon Sep 17 00:00:00 2001
From: Martin Zietz <zietz@ksat-stuttgart.de>
Date: Wed, 10 Feb 2021 11:46:23 +0100
Subject: [PATCH] workaround for thread end problem on program close

---
 User_Interface.py | 2 +-
 csv_threading.py  | 8 +++++---
 main.py           | 5 ++++-
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/User_Interface.py b/User_Interface.py
index 7226c5a..5e7c224 100644
--- a/User_Interface.py
+++ b/User_Interface.py
@@ -626,7 +626,7 @@ class ExecuteCSVMode(Frame):
         self.stop_button["state"] = "normal"
         self.reinit_button["state"] = "disabled"
 
-        # g.threadLock = threading.Lock()  # create thread locking object, used to ensure all devices switch at once later
+        g.threadLock = threading.Lock()  # create thread locking object, used to ensure all devices switch at once later
         # create separate thread to run sequence execution in:
         self.csv_thread = csv.ExecCSVThread("CSV_Thread", self.sequence_array, self, self.controller)
         self.csv_thread.start()  # start thread
diff --git a/csv_threading.py b/csv_threading.py
index b43556c..ad80021 100644
--- a/csv_threading.py
+++ b/csv_threading.py
@@ -56,15 +56,17 @@ class ExecCSVThread(Thread):
 
             t = time.time() - t_zero  # get relative time
             if t >= array[i, 0]:  # time for this row has come
-                # g.threadLock.acquire(0)
+                g.threadLock.acquire()  # execute the next few lines before going back to the main thread
+
                 field_vec = array[i, 1:4]  # extract desired field vector
-                ui.ui_print("%f s: t = %0.2f s, target field vector = "
+                ui.ui_print("%f s: t = %0.2f s, target field vector = "  # ToDo: better printing
                             % (time.time() - t_zero, array[i, 0]), field_vec * 1e6, "\u03BCT")
                 func.set_field(field_vec)  # send field vector to test stand
                 ui.ui_print(time.time() - t_zero)
                 controller.StatusDisplay.update_labels()  # update status display after change
                 i = i + 1  # next row
-                # g.threadLock.release()
+
+                g.threadLock.release()  # allow going back to main thread now
 
             elif t >= array[i, 0] - delay - 0.02:  # next change time is close, not enough time to sleep
                 pass
diff --git a/main.py b/main.py
index 22b374e..14f02e0 100644
--- a/main.py
+++ b/main.py
@@ -1,6 +1,7 @@
 from os.path import exists
 import traceback
 from tkinter import messagebox
+import time
 
 import cage_func as func
 from User_Interface import HelmholtzGUI
@@ -15,7 +16,9 @@ def program_end():
     if g.app is not None:
         if g.app.pages[ui.ExecuteCSVMode].csv_thread is not None:  # end possible csv execution thread
             g.app.pages[ui.ExecuteCSVMode].csv_thread.stop()  # stop thread
-            g.app.pages[ui.ExecuteCSVMode].csv_thread.join()  # wait for thread to finish
+            # g.app.pages[ui.ExecuteCSVMode].csv_thread.join()  # wait for thread to finish
+            # ToDo: figure out why this doesn't work with join()
+            time.sleep(0.2)  # give the thread time to finish, workaround to avoid join()
     # g.app = None  # reset to None so nothing tries to print in the UI output
     func.shut_down_all()  # shut down devices
     if g.app is not None: