Question

我有一个简单的进度条，我想在循环中弹出，如下例所示。

我必须在应用程序之外实例化它，然后调整循环的值。为什么？我会认为在MainWindow中实例化一个新的进度条类是更理想的，但是没有显示出来。我认为它与app.exec有关。但是，如果我为进度条添加self.exec，它不会更新，那么实现它的正确方法是什么？

from PyQt5.Qt import *
import sys

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        self.centralwidget = QWidget(MainWindow)
        self.pushButton = QPushButton(self.centralwidget)
        self.pushButton.setText("CLICK ME")
        MainWindow.setCentralWidget(self.centralwidget)
        self.pushButton.clicked.connect(self.testloop)


    def testloop(self):
        n = 200
        print(progressbar.wasCanceled())
        progressbar.setMinimum(0)
        progressbar.setValue(0)
        progressbar.setMaximum(n)
        progressbar.show()

        for i in range(n):
            progressbar.setValue(i)
            if progressbar.wasCanceled(): # How can I un-cancel and reset the progress bar again?
                break


class ProgressBar(QProgressDialog):
    def __init__(self):
        super().__init__()
        self.setValue(0)
        self.setModal(True)

    def step(self, i):
        self.setValue(i)

if __name__ == "__main__":
    app = QApplication(sys.argv)
    mainwindow = QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(mainwindow)
    mainwindow.show()

    progressbar = ProgressBar() # Do I need to instantiate a progressbar here,
                                # or can I instantiate and kill it inside the app code?

    sys.exit(app.exec_())

Answer 1

简单实现循环的进度条：

from PyQt5.Qt import *
import sys
import time

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        self.centralwidget = QWidget(MainWindow)
        self.pushButton = QPushButton(self.centralwidget)
        self.pushButton.setText("CLICK ME")
        MainWindow.setCentralWidget(self.centralwidget)
        self.pushButton.clicked.connect(self.testloop)


    def testloop(self):
        n = 10

        progressbar = ProgressBar(n, title = "Copying files...")

        for i in range(n):
            time.sleep(0.01)
            progressbar.setValue(i)
            if progressbar.wasCanceled():
                break


class ProgressBar(QProgressDialog):
    def __init__(self, max, title):
        super().__init__()
        self.setMinimumDuration(0) # Sets how long the loop should last before progress bar is shown (in miliseconds)
        self.setWindowTitle(title)
        self.setModal(True)

        self.setValue(0)
        self.setMinimum(0)
        self.setMaximum(max)

        self.show()


if __name__ == "__main__":
    app = QApplication(sys.argv)
    mainwindow = QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(mainwindow)
    mainwindow.show()

    sys.exit(app.exec_())

带QProgressDialog的PyQt进度条无法重置

1 个答案: