PyQt类继承 [英] PyQt class inheritance

问题描述

我很难理解Python/PyQt的类继承.我有一个MainWindow和一个弹出QWidget.在弹出窗口中打开QWidget后，我想与MainWindow的self.label1进行交互，但是我不知道该怎么做.我只知道相反的一种方法，可以从MainWindow内的弹出窗口访问所有小部件，反之亦然.

I am having troubles to understand class inheritance with Python/PyQt. I have a MainWindow and a Popup QWidget. I want to interact with the self.label1 of the MainWindow after the QWidget was opened in a pop up window but I don't know how to do it. I know only the other way around, to reach all widgets from the popup Window inside MainWindow but not vice versa.

这里是一个示例，在新窗口中打开MyPopup后，MainWindow的self.label1应该会得到另一个文本:

Here is an example, self.label1 of MainWindow should get another text after MyPopup opens in a new window:

import sys
from PyQt4.Qt import *

class MyPopup(QWidget):
    def __init__(self):
        QWidget.__init__(self)

        # I want to change the lable1 of MainWindow
        self.cw.label1.setText('hello')


class MainWindow(QMainWindow):
    def __init__(self, *args):
        QMainWindow.__init__(self, *args)
        self.cw = QWidget(self)
        self.setCentralWidget(self.cw)
        self.btn1 = QPushButton("Click me", self.cw)
        self.btn1.setGeometry(QRect(50, 50, 100, 30))
        self.label1 = QLabel("No Commands running", self.cw)
        self.connect(self.btn1, SIGNAL("clicked()"), self.doit)
        self.w = None

    def doit(self):
        self.w = MyPopup()
        self.w.setGeometry(QRect(100, 100, 400, 200))
        self.w.show()

if __name__ == "__main__":
    app = QApplication(sys.argv)
    myapp = MainWindow()
    myapp.show()
    sys.exit(app.exec_())

推荐答案

您需要将主窗口作为参数传递给MyPopup的构造函数，请尝试以下操作:

You need to pass the main window as a parameter to the constructor of MyPopup, try this:

import sys
from PyQt4.Qt import *

class MyPopup(QWidget):
    def __init__(self, mainWindow):
        QWidget.__init__(self)

        # use the mainWindow passed as parameter
        mainWindow.label1.setText('hello')


class MainWindow(QMainWindow):
    def __init__(self, *args):
        QMainWindow.__init__(self, *args)
        self.cw = QWidget(self)
        self.setCentralWidget(self.cw)
        self.btn1 = QPushButton("Click me", self.cw)
        self.btn1.setGeometry(QRect(50, 50, 100, 30))
        self.label1 = QLabel("No Commands running", self.cw)
        self.connect(self.btn1, SIGNAL("clicked()"), self.doit)
        self.w = None

    def doit(self):
        self.w = MyPopup(self) #when creating the popup pass in the main window
        self.w.setGeometry(QRect(100, 100, 400, 200))
        self.w.show()

if __name__ == "__main__":
    app = QApplication(sys.argv)
    myapp = MainWindow()
    myapp.show()
    sys.exit(app.exec_())

这篇关于PyQt类继承的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！