Can't get pyqtgraph chart to update - python-3.x

Question

I'm trying to import tick data from MT5 and display it on a candlestick chart in pyqtgraph but the graph only displays the first two candles which are preloaded to meet minimum data requirements to prevent an exception.
Beyond the original two candles the chart does not update with new values.
import pyqtgraph as pg
import numpy as np
from PyQt5 import QtWidgets, QtCore, QtGui
from pyqtgraph import PlotWidget, plot, QtCore, QtGui
import sys
import os
from random import randint
import time
import threading
import os
import queue
import random
import copy
import MetaTrader5 as mt5
from datetime import datetime
#------------------------------------------------------------------------------
'''chart items'''
class CandlestickItem(pg.GraphicsObject):
_boundingRect = QtCore.QRectF()
# ...
def __init__(self):
pg.GraphicsObject.__init__(self)
self.flagHasData = False
def set_data(self, data):
self.data = data
self.flagHasData = True
self.generatePicture()
self.informViewBoundsChanged()
def generatePicture(self):
self.picture = QtGui.QPicture()
path = QtGui.QPainterPath()
p = QtGui.QPainter(self.picture)
p.setPen(pg.mkPen('w'))
w = (self.data[1][0] - self.data[0][0]) / 3.
for (t, open, close) in self.data:
# line = QtCore.QLineF(t, min, t, max)
# path.moveTo(line.p1())
# path.lineTo(line.p2())
# p.drawLine(line)
rect = QtCore.QRectF(t-w, open, w*2, close-open)
path.addRect(rect)
if open > close:
p.setBrush(pg.mkBrush('r'))
else:
p.setBrush(pg.mkBrush('g'))
p.drawRect(rect)
p.end()
self._boundingRect = path.boundingRect()
def paint(self, p, *args):
if self.flagHasData:
p.drawPicture(0, 0, self.picture)
def boundingRect(self):
return self._boundingRect
#------------------------------------------------------------------------------
# establish connection to the MetaTrader 5 terminal
if not mt5.initialize():
print("initialize() failed, error code =",mt5.last_error())
quit()
# attempt to enable the display of the GBPUSD in MarketWatch
selected=mt5.symbol_select("EURUSD",True)
if not selected:
print("Failed to select EURUSD")
mt5.shutdown()
quit()
#------------------------------------------------------------------------------
class tick:
last_tick = 0
current_tick = 0
current_tick_number = 1
def __init__(self):
self.tick_array = np.zeros((100000,3), dtype = float)
self.pass_data = False
def _time(self, tick_index_number):
return self.tick_array[self.tick_index(tick_index_number),0]
def _open(self, tick_index_number):
# print(tick_index_number)
return self.tick_array[self.tick_index(tick_index_number),1]
def _close(self, tick_index_number):
return self.tick_array[self.tick_index(tick_index_number),2]
def _min(self, tick_index_number):
return self.tick_array[self.tick_index(tick_index_number),3]
def _max(self, tick_index_number):
return self.tick_array[self.tick_index(tick_index_number),4]
#return a negative index of n
def tick_index(self, n = 0):
return self.current_tick_number - n
#gets EURUSD current tick values
def get_tick(self):
return mt5.symbol_info_tick("EURUSD")
#add self.time/bid/ask to get_tick instead
#------------------------------------------------------------------------------
#updates tick array
def update_tick(self):
while True:
#get current tick value
current_tick = self.get_tick()
#if current tick is unique, add that value to last_tick and continue
if self.last_tick != current_tick:
self.last_tick = current_tick
#update the array with the new tick values
self.tick_array[self.current_tick_number,0], self.tick_array[self.current_tick_number,1], self.tick_array[self.current_tick_number,2] = datetime.fromtimestamp(current_tick[5] / 1000.0).strftime("%m%d%Y%I%M%S"), self.tick_array[self.current_tick_number-1, 2] , current_tick[1]
self.current_tick_number += 1
q.put(self.tick_array[:self.current_tick_number])
def tick_datafeed(self):
return self.tick_array[:self.current_tick_number]
tick = tick()
#------------------------------------------------------------------------------
''' launch threads that work the chart'''
class Threads:
def __init__(self):
pass
def thread_launch_update_tick(self):
t1 = threading.Thread(target = tick.update_tick, args = ())
t1.start()
def thread_launch_get_data_from_update(self):
t2 = threading.Thread(target = get_data_from_update, args = ())
t2.start()
def get_data_from_update():
while True:
i = q.get()
item.set_data(i)
print(tick.tick_array[:tick.current_tick_number])
q.task_done()
#------------------------------------------------------------------------------
app = QtWidgets.QApplication([])
item = CandlestickItem()
item.set_data(tick.tick_array[:tick.current_tick_number + 1])
plt = pg.plot()
plt.addItem(item)
plt.setWindowTitle('pyqtgraph example: customGraphicsItem')
q = queue.Queue()
threads = Threads()
threads.thread_launch_get_data_from_update()
threads.thread_launch_update_tick()
#------------------------------------------------------------------------------
if __name__ == '__main__':
# window = Window()
import sys
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtWidgets.QApplication.instance().exec_()
The resulting array data looks like this
which is comprised of the [date in unix, last tick, current tick] aka time/open/close
[[0.00000000e+00 0.00000000e+00 0.00000000e+00]
[7.26202211e+12 0.00000000e+00 1.01348000e+00]
[7.26202211e+12 1.01348000e+00 1.01349000e+00]
[7.26202211e+12 1.01349000e+00 1.01348000e+00]
[7.26202211e+12 1.01348000e+00 1.01347000e+00]
[7.26202211e+12 1.01347000e+00 1.01348000e+00]
[7.26202211e+12 1.01348000e+00 1.01347000e+00]
[7.26202211e+12 1.01347000e+00 1.01348000e+00]
[7.26202211e+12 1.01348000e+00 1.01347000e+00]
[7.26202211e+12 1.01347000e+00 1.01346000e+00]
[7.26202211e+12 1.01346000e+00 1.01347000e+00]
[7.26202211e+12 1.01347000e+00 1.01346000e+00]]
Can anyone point out my flaw?
The get_data_from_update() function should update the chart but it simply doesn't work for reasons that are beyond me.