Use the NEW Timeout capability for timing... no more sleeps

Demo_Desktop_Widget_Timer.py

@@ -1,6 +1,5 @@
 #!/usr/bin/env python
 import sys
-import sys
 if sys.version_info[0] >= 3:
     import PySimpleGUI as sg
 else:
@@ -8,7 +7,15 @@ else:
 import time
 
 """
- Timer Desktop Widget Creates a floating timer that is always on top of other windows You move it by grabbing anywhere on the window Good example of how to do a non-blocking, polling program using PySimpleGUI Can be used to poll hardware when running on a Pi     NOTE - you will get a warning message printed when you exit using exit button.
+ Timer Desktop Widget Creates a floating timer that is always on top of other windows You move it by grabbing anywhere on the window Good example of how to do a non-blocking, polling program using SimpleGUI Can be used to poll hardware when running on a Pi
+ 
+ While the timer ticks are being generated by PySimpleGUI's "timeout" mechanism, the actual value
+  of the timer that is displayed comes from the system timer, time.time().  This guarantees an
+  accurate time value is displayed regardless of the accuracy of the PySimpleGUI timer tick. If
+  this design were not used, then the time value displayed would slowly drift by the amount of time
+  it takes to execute the PySimpleGUI read and update calls (not good!)     
+ 
+ NOTE - you will get a warning message printed when you exit using exit button.
  It will look something like: invalid command name \"1616802625480StopMove\"
 """
 
@@ -32,14 +39,14 @@ start_time = int(round(time.time() * 100))
 while (True):
     # --------- Read and update window --------
     if not paused:
-        event, values = window.ReadNonBlocking()
+        event, values = window.Read(timeout=10)
         current_time = int(round(time.time() * 100)) - start_time
     else:
         event, values = window.Read()
     if event == 'button':
         event = window.FindElement(event).GetText()
     # --------- Do Button Operations --------
-    if values is None or event == 'Exit':
+    if event is None or event == 'Exit':        # ALWAYS give a way out of program
         break
     if event is 'Reset':
         start_time = int(round(time.time() * 100))
@@ -60,9 +67,5 @@ while (True):
     window.FindElement('text').Update('{:02d}:{:02d}.{:02d}'.format((current_time // 100) // 60,
                                                                   (current_time // 100) % 60,
                                                                   current_time % 100))
-    time.sleep(.01)
 
 # --------- After loop --------
-
-# Broke out of main loop. Close the window.
-window.CloseNonBlocking()