python - PyQt 进度条直到 100% 才更新或出现

Question

编辑:PyQt4 进度条上有许多类似的帖子没有更新。他们都关注线程问题以及程序实际更新窗口的位置。虽然有用，但我的代码结构如此之大以至于回复不切实际。此处给出的公认答案简单明了且有效。

我在 Win 7 x64 机器上使用 Python 2.7 和 PyQT 4。

我正在尝试清除窗口中的一个小部件，一个“接受”按钮，查看代码，并将其替换为进度条。

即使我在进入处理循环之前关闭了“接受”按钮并添加了进度条。窗口仅在循环结束后更新，进度条直接跳到 100%。

我的代码，

from PyQt4 import QtCore, QtGui
import sys
import time

class CentralWidget(QtGui.QWidget):

    def __init__(self, parent=None):
        super(CentralWidget, self).__init__(parent)

        # set layouts
        self.layout = QtGui.QVBoxLayout(self)

        # Poly names
        self.pNames = QtGui.QLabel("Import file name", self)  
        self.polyNameInput = QtGui.QLineEdit(self) 

        # Polytype selection
        self.polyTypeName = QtGui.QLabel("Particle type", self)
        polyType = QtGui.QComboBox(self)
        polyType.addItem("")
        polyType.addItem("Random polyhedra")
        polyType.addItem("Spheres")
        polyType.addItem("Waterman polyhedra")
        polyType.activated[str].connect(self.onActivated)

        # Place widgets in layout        
        self.layout.addWidget(self.pNames)
        self.layout.addWidget(self.polyNameInput)
        self.layout.addWidget(self.polyTypeName)
        self.layout.addWidget(polyType)
        self.layout.addStretch()

    # Combobox choice
    def onActivated(self, text):

        if text=="Random polyhedra":
            self.randomPolyhedra(text)     
        if text=="Spheres":         # not implementaed yet
            self.polyTypeName.setText("Not implemented yet.")
            self.polyTypeName.adjustSize()      
        if text=="Waterman polyhedra": # not implementaed yet
            self.polyTypeName.setText("Not implemented yet.")
            self.polyTypeName.adjustSize()   

    # New options for random polyhedra choice    
    def randomPolyhedra(self, text):    

        self.polyNumberLbl = QtGui.QLabel("How many: ", self)            
        self.polyNumber = QtGui.QLineEdit(self) 
        self.acceptSeed = QtGui.QPushButton('Accept') # Accept button created
        self.acceptSeed.clicked.connect(lambda: self.ranPolyGen())
        self.layout.addWidget(self.polyNumberLbl)
        self.layout.addWidget(self.polyNumber)
        self.layout.addWidget(self.acceptSeed)      # Accept button in layout
        self.randFlag = True
        self.polyTypeName.setText(text)
        self.polyTypeName.adjustSize()

    # Act on option choices for random polyhedra 
    def ranPolyGen(self):

        polyCount = int(self.polyNumber.text())
        self.progressBar = QtGui.QProgressBar() # Progress bar created
        self.progressBar.setMinimum(1)
        self.progressBar.setMaximum(polyCount)
        self.acceptSeed.close()                 # Accept button closed
        self.layout.addWidget(self.progressBar) # Add progressbar to layout
        for poly in range(1, polyCount+1):
            time.sleep(1) # Calls to main polyhedral generating code go here
            print poly
            self.progressBar.setValue(poly)
        self.doneLbl = QtGui.QLabel("Done", self)
        self.layout.addWidget(self.doneLbl)

# Creates GUI
class Polyhedra(QtGui.QMainWindow):

    def __init__(self):

        super(Polyhedra, self).__init__()

        # Place central widget in layout
        self.central_widget = CentralWidget(self)
        self.setCentralWidget(self.central_widget)

        # Set up window        
        self.setGeometry(500, 500, 300, 300)
        self.setWindowTitle('Pyticle')
        self.show()

    # Combo box
    def onActivated(self, text):

        self.central_widget.onActivated(text)


def main():

    app = QtGui.QApplication(sys.argv)
    poly = Polyhedra()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

下面是循环执行期间和完成后的图片。

我不认为我已经了解 addWidget() 方法。我的印象是这会将另一个小部件添加到当前布局(此处为 vbox 布局)并且 .close() 方法在指示时删除了一个小部件。

我错过了什么？

Answer 1

您可以添加:

from PyQt4.QtGui import QApplication

然后在你的 for 循环中:

QApplication.processEvents() 

您的应用实际上变得无响应，您需要调用 processEvents() 来处理事件并重新绘制图形用户界面。我不太熟悉 pyqt，但我想另一种选择是使用线程。