Overdrivr · October 25, 2023 12:49 · Feb 7, 2016 · Feb 7, 2016
diff --git a/Plot.py b/Plot.py
@@ -43,11 +43,9 @@ def io(running,q):
         time.sleep(0.01)
     print("Done")
 
-## Start Qt event loop unless running in interactive mode or using pyside.
 if __name__ == '__main__':
-    manager = Manager()
     q = Queue()
-
+    # Event for stopping the IO thread
     run = threading.Event()
     run.set()
 
@@ -58,7 +56,7 @@ def io(running,q):
     # Start display process
     p = Process(target=display, args=('bob',q))
     p.start()
-    input("Type any key to quit.")
+    input("See ? Main process immediately free ! Type any key to quit.")
     run.clear()
     print("Waiting for scheduler thread to join...")
     t.join()

diff --git a/Plot.py b/Plot.py
@@ -0,0 +1,67 @@
+# -*- coding: utf-8 -*-
+from pyqtgraph.Qt import QtGui, QtCore
+import numpy as np
+import pyqtgraph as pg
+from multiprocessing import Process, Manager, Queue
+import sched, time, threading
+
+# This function is responsible for displaying the data
+# it is run in its own process to liberate main process
+def display(name,q):
+    app2 = QtGui.QApplication([])
+
+    win2 = pg.GraphicsWindow(title="Basic plotting examples")
+    win2.resize(1000,600)
+    win2.setWindowTitle('pyqtgraph example: Plotting')
+    p2 = win2.addPlot(title="Updating plot")
+    curve = p2.plot(pen='y')
+
+    x_np = []
+    y_np = []
+
+    def updateInProc(curve,q,x,y):
+        item = q.get()
+        x.append(item[0])
+        y.append(item[1])
+        curve.setData(x,y)
+
+    timer = QtCore.QTimer()
+    timer.timeout.connect(lambda: updateInProc(curve,q,x_np,y_np))
+    timer.start(50)
+
+    QtGui.QApplication.instance().exec_()
+
+# This is function is responsible for reading some data (IO, serial port, etc)
+# and forwarding it to the display
+# it is run in a thread
+def io(running,q):
+    t = 0
+    while running.is_set():
+        s = np.sin(2 * np.pi * t)
+        t += 0.01
+        q.put([t,s])
+        time.sleep(0.01)
+    print("Done")
+
+## Start Qt event loop unless running in interactive mode or using pyside.
+if __name__ == '__main__':
+    manager = Manager()
+    q = Queue()
+
+    run = threading.Event()
+    run.set()
+
+    # Run io function in a thread
+    t = threading.Thread(target=io, args=(run,q))
+    t.start()
+
+    # Start display process
+    p = Process(target=display, args=('bob',q))
+    p.start()
+    input("Type any key to quit.")
+    run.clear()
+    print("Waiting for scheduler thread to join...")
+    t.join()
+    print("Waiting for graph window process to join...")
+    p.join()
+    print("Process joined successfully. C YA !")