1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
from PySide6.QtCore import (Qt, QEvent, QObject, QTimer, Signal, Slot)
from PySide6.QtGui import (QColor, QFont, QPalette)
from PySide6.QtWidgets import (QApplication, QGridLayout, QLabel, QMainWindow, QVBoxLayout, QWidget)
import asyncio
import signal
import sys
from random import randint
class MainWindow(QMainWindow):
set_num = Signal(int, QColor)
def __init__(self, rows, cols):
super().__init__()
self.rows = rows
self.cols = cols
widget_central = QWidget()
self.setCentralWidget(widget_central)
layout_outer = QVBoxLayout(widget_central)
self.widget_outer_text = QLabel()
font = QFont()
font.setPointSize(14)
self.widget_outer_text.setFont(font)
layout_outer.addWidget(self.widget_outer_text, alignment=Qt.AlignmentFlag.AlignCenter)
widget_inner_grid = QWidget()
layout_outer.addWidget(widget_inner_grid, alignment=Qt.AlignmentFlag.AlignCenter)
self.layout_inner_grid = QGridLayout(widget_inner_grid)
k = 1
for i in range(self.rows):
for j in range(self.cols):
box = QLabel(f"{k}")
self.layout_inner_grid.addWidget(box, i, j, Qt.AlignmentFlag.AlignCenter)
k += 1
self.set_num.connect(self.set_num_handler)
@Slot(int, QColor)
def set_num_handler(self, i, color):
row = int((i - 1) / self.cols)
col = (i - 1) - (row * self.cols)
widget = self.layout_inner_grid.itemAtPosition(row, col).widget()
font = QFont()
font.setWeight(QFont.Bold)
palette = QPalette()
palette.setColor(QPalette.WindowText, color)
widget.setFont(font)
widget.setPalette(palette)
class Eratosthenes(QObject):
done_signal = Signal()
""" This Sieve of Eratosthenes runs on a configurable tick (default
0.1 seconds). At each tick, a new subroutine will be created
that will check multiples of the next prime number. Each of
these subroutines also operates on the same tick. """
def __init__(self, num, window, tick=0.1):
super().__init__()
self.num = num
self.sieve = [True] * self.num
self.base = 0
self.window = window
self.tick = tick
self.coroutines = []
self.done = False
self.loop = None
def get_tick(self):
return self.loop.time() + self.tick
async def start(self):
self.loop = asyncio.get_event_loop()
asyncio.create_task(self.update_text())
while self.base <= self.num / 2:
await asyncio.sleep(self.tick)
for i in range(self.base + 1, self.num):
if self.sieve[i]:
self.base = i
break
asyncio.create_task(self.mark_number(self.base + 1))
while sum(self.coroutines) > 0:
await asyncio.sleep(self.tick)
self.done = True
async def mark_number(self, base):
id = len(self.coroutines)
self.coroutines.append(1)
color = QColor(randint(64, 192), randint(64, 192), randint(64, 192))
for i in range(2 * base, self.num + 1, base):
if self.sieve[i - 1]:
self.sieve[i - 1] = False
self.window.set_num.emit(i, color)
await asyncio.sleep(self.tick)
self.coroutines[id] = 0
async def update_text(self):
while not self.done:
await asyncio.sleep(self.tick)
if int(self.loop.time() + self.tick) % 2:
text = "⚙️ ...Calculating prime numbers... ⚙️"
else:
text = "👩💻 ...Hacking the universe... 👩💻"
self.window.widget_outer_text.setText(text)
self.window.widget_outer_text.setText(
"🥳 Congratulations! You found all the prime numbers and solved mathematics. 🥳"
)
# This signals to the guest run when there are no more asyncio tasks
# left so its event loop can finish.
self.done_signal.emit()
class AsyncHelper(QObject):
class ReenterQtObject(QObject):
""" This is a QObject to which an event will be posted, allowing
asyncio to resume when the event is handled. event.fn() is
the next entry point of the asyncio event loop. """
def event(self, event):
if event.type() == QEvent.Type.User + 1:
event.fn()
return True
return False
class ReenterQtEvent(QEvent):
""" This is the QEvent that will be handled by the ReenterQtObject.
self.fn is the next entry point of the asyncio event loop. """
def __init__(self, fn):
super().__init__(QEvent.Type(QEvent.Type.User + 1))
self.fn = fn
def __init__(self, worker, entry):
super().__init__()
self.reenter_qt = self.ReenterQtObject()
self.entry = entry
self.loop = asyncio.new_event_loop()
self.done = False
self.worker = worker
if hasattr(self.worker, "start_signal") and isinstance(self.worker.start_signal, Signal):
self.worker.start_signal.connect(self.on_worker_started)
if hasattr(self.worker, "done_signal") and isinstance(self.worker.done_signal, Signal):
self.worker.done_signal.connect(self.on_worker_done)
@Slot()
def on_worker_started(self):
""" To use asyncio and Qt together, one must run the asyncio
event loop as a "guest" inside the Qt "host" event loop. """
if not self.entry:
raise Exception("No entry point for the asyncio event loop was set.")
asyncio.set_event_loop(self.loop)
self.loop.create_task(self.entry())
self.loop.call_soon(self.next_guest_run_schedule)
self.done = False # Set this explicitly as we might want to restart the guest run.
self.loop.run_forever()
@Slot()
def on_worker_done(self):
""" When all our current asyncio tasks are finished, we must end
the "guest run" lest we enter a quasi idle loop of switching
back and forth between the asyncio and Qt loops. We can
launch a new guest run by calling launch_guest_run() again. """
self.done = True
def continue_loop(self):
""" This function is called by an event posted to the Qt event
loop to continue the asyncio event loop. """
if not self.done:
self.loop.call_soon(self.next_guest_run_schedule)
self.loop.run_forever()
def next_guest_run_schedule(self):
""" This function serves to pause and re-schedule the guest
(asyncio) event loop inside the host (Qt) event loop. It is
registered in asyncio as a callback to be called at the next
iteration of the event loop. When this function runs, it
first stops the asyncio event loop, then by posting an event
on the Qt event loop, it both relinquishes to Qt's event
loop and also schedules the asyncio event loop to run again.
Upon handling this event, a function will be called that
resumes the asyncio event loop. """
self.loop.stop()
QApplication.postEvent(self.reenter_qt, self.ReenterQtEvent(self.continue_loop))
if __name__ == "__main__":
rows = 40
cols = 40
num = rows * cols
app = QApplication(sys.argv)
main_window = MainWindow(rows, cols)
eratosthenes = Eratosthenes(num, main_window)
async_helper = AsyncHelper(eratosthenes, eratosthenes.start)
# This establishes the entry point for the asyncio guest run. It
# varies depending on how and when its event loop is to be
# triggered, e.g., from the beginning (as here) or rather at a
# specific moment like a button press.
QTimer.singleShot(0, async_helper.on_worker_started)
main_window.show()
signal.signal(signal.SIGINT, signal.SIG_DFL)
app.exec()
|
