代码之家 › 专栏 › 技术社区 › Spencer

PyQt4:使用QTimer不断更新进度条

qprogressbar qtimer signals-slots pyqt4 python

2

Spencer · 技术社区 · 7 年前

我有一个简单的对话框,其中有三个进度条,我想不断更新(显示系统资源使用情况)。通过阅读文档, QTimer 启动函数的正确方法是 x

这是我的代码:

import sys
from PyQt4 import QtGui, QtCore
import psutil

class Tiny_System_Monitor(QtGui.QWidget):
    def __init__(self):
        super(Tiny_System_Monitor, self).__init__()
        self.initUI()

    def initUI(self):
        mainLayout = QtGui.QHBoxLayout()

        self.cpu_progressBar = QtGui.QProgressBar()
        self.cpu_progressBar.setTextVisible(False)
        self.cpu_progressBar.setOrientation(QtCore.Qt.Vertical)
        mainLayout.addWidget(self.cpu_progressBar)

        self.vm_progressBar = QtGui.QProgressBar()
        self.vm_progressBar.setOrientation(QtCore.Qt.Vertical)
        mainLayout.addWidget(self.vm_progressBar)

        self.swap_progressBar = QtGui.QProgressBar()
        self.swap_progressBar.setOrientation(QtCore.Qt.Vertical)
        mainLayout.addWidget(self.swap_progressBar)

        self.setLayout(mainLayout)

        timer = QtCore.QTimer()
        timer.timeout.connect(self.updateMeters)
        timer.start(1000)

    def updateMeters(self):
        cpuPercent = psutil.cpu_percent()
        vmPercent = getattr(psutil.virtual_memory(), "percent")
        swapPercent = getattr(psutil.swap_memory(), "percent")

        self.cpu_progressBar.setValue(cpuPercent)
        self.vm_progressBar.setValue(vmPercent)
        self.swap_progressBar.setValue(swapPercent)
        print "updated meters"

def main():
    app = QtGui.QApplication(sys.argv)
    ex = Tiny_System_Monitor()

    ex.show()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

1 回复 | 直到 7 年前

1

3

ekhumoro 7 年前

您必须保留对计时器对象的引用,否则它将立即被垃圾收集 initUI 返回:

class Tiny_System_Monitor(QtGui.QWidget):
    ...
    def initUI(self):
        ...    
        self.timer = QtCore.QTimer()
        self.timer.timeout.connect(self.updateMeters)
        self.timer.start(1000)