<p>应用程序是在一个或多个前台线程上运行的可执行进程,每个前台线程还可以启动后台线程来执行并行操作或操作,而不会阻塞调用线程。应用程序将在所有前台线程结束后终止,因此,在您的情况下,至少需要一个前台线程,该线程是在调用<code>app.exec_()</code>语句时创建的。在GUI应用程序中,这是UI线程,您应该在其中创建并显示主窗口和任何其他UI小部件。当所有窗口小部件关闭时,Qt将自动终止您的应用程序进程</p>
<p>IMHO,您应该尽可能地遵循上面描述的正常流程,工作流可以如下所示:</p>
<blockquote>
<p>Start Application > Create main window > Start a background thread for each calculation > Send progress to UI thread > Show results in a window after each calculation is finished > Close all windows > End application</p>
</blockquote>
<p>另外,您应该使用<code>ThreadPool</code>来确保资源不会耗尽</p>
<p>下面是一个完整的示例:</p>
<pre><code>import sys
import time
import PyQt5
from PyQt5 import QtCore, QtWidgets
from PyQt5.QtCore import QRunnable, pyqtSignal, QObject
from PyQt5.QtWidgets import QApplication, QMainWindow, QWidget, QDialog
class CaptureDataTaskStatus(QObject):
progress = pyqtSignal(int, int) # This signal is used to report progress to the UI thread.
captureDataFinished = pyqtSignal(dict) # Assuming your result is a dict, this can be a class, a number, etc..
class CaptureDataTask(QRunnable):
def __init__(self, num_measurements):
super().__init__()
self.num_measurements = num_measurements
self.status = CaptureDataTaskStatus()
def run(self):
for i in range(0, self.num_measurements):
# Report progress
self.status.progress.emit(i + 1, self.num_measurements)
# Make your equipment measurement here
time.sleep(0.1) # Wait for some time to mimic a long action
# At the end you will have a result, for example
result = {'a': 1, 'b': 2, 'c': 3}
# Send it to the UI thread
self.status.captureDataFinished.emit(result)
class ResultWindow(QWidget):
def __init__(self, result):
super().__init__()
# Display your result using widgets...
self.result = result
# For this example I will just print the dict values to the console
print('a: {}'.format(result['a']))
print('b: {}'.format(result['b']))
print('c: {}'.format(result['c']))
class MainWindow(QMainWindow):
def __init__(self, *args, **kwargs):
super(MainWindow, self).__init__(*args, **kwargs)
self.result_windows = []
self.thread_pool = QtCore.QThreadPool().globalInstance()
# Change the following to suit your needs (I just put 1 here so you can see each task opening a window while the others are still running)
self.thread_pool.setMaxThreadCount(1)
# You could also start by clicking a button, menu, etc..
self.start_capturing_data()
def start_capturing_data(self):
# Here you start data capture tasks as needed (I just start 3 as an example)
for setting in range(0, 3):
capture_data_task = CaptureDataTask(300)
capture_data_task.status.progress.connect(self.capture_data_progress)
capture_data_task.status.captureDataFinished.connect(self.capture_data_finished)
self.thread_pool.globalInstance().start(capture_data_task)
def capture_data_progress(self, current, total):
# Update progress bar, label etc... for this example I will just print them to the console
print('Current: {}'.format(current))
print('Total: {}'.format(total))
def capture_data_finished(self, result):
result_window = ResultWindow(result)
self.result_windows.append(result_window)
result_window.show()
class App(QApplication):
"""Main application wrapper, loads and shows the main window"""
def __init__(self, sys_argv):
super().__init__(sys_argv)
self.main_window = MainWindow()
self.main_window.show()
if __name__ == '__main__':
app = App(sys.argv)
sys.exit(app.exec_())
</code></pre>