为什么我的第二个 window 有不同的布局？

Question

我正在使用 PyQt5 创建多个 windows。这些 windows 应该能够在不弹出新 windows 的情况下更改视图。但是，当使用完全相同的布局和按钮向主 window 添加另一个 window 时，window 布局会有所不同。

我想要的是使用与 Main window 完全相同的布局选项。我的代码可以在下面找到：

from PyQt5 import QtWidgets, QtCore, QtGui
from PyQt5.QtCore import Qt
import sys

class mainWindow(QtWidgets.QMainWindow):
    def __init__(self):
        super().__init__()
        # MAIN WINDOW SETTINGS
        self.central_widget = QtWidgets.QStackedWidget()
        self.setGeometry(400, 150, 1200, 700)
        self.setWindowTitle('Main window')
        
        # COMPOSE MAIN WINDOW
        self.settings = {'grid': {'row': [5,0,0,0,1], 'column': [1,3,1,1]}}
        self.grid = QtWidgets.QGridLayout()
        self.grid.setVerticalSpacing(20)
        for row, stretch in enumerate(self.settings['grid']['row']):
            self.grid.setRowStretch(row, stretch)
        for column, stretch in enumerate(self.settings['grid']['column']):
            self.grid.setColumnStretch(column, stretch)
            
        self.b1 = QtWidgets.QPushButton("Button 1")
        self.b1.clicked.connect(lambda: self.b1_handler('second window'))
        self.b2 = QtWidgets.QPushButton("Button 2")
        self.b2.clicked.connect(self.b2_handler)
        self.b3 = QtWidgets.QPushButton("Button 3")
        self.b3.clicked.connect(self.b3_handler)
        self.b4 = QtWidgets.QPushButton("Button 4")
        self.b4.clicked.connect(self.b4_handler)
        self.b5 = QtWidgets.QPushButton("Button 5")
        self.b5.clicked.connect(self.b5_handler)       
        
        self.grid.addWidget(self.b1, 1, 1)
        self.grid.addWidget(self.b2, 1, 2)
        self.grid.addWidget(self.b3, 2, 1)
        self.grid.addWidget(self.b4, 3, 1)
        self.grid.addWidget(self.b5, 4, 3)
        
        self.main_window = QtWidgets.QWidget()
        self.main_window.setLayout(self.grid)
        
        # TEST WINDOW
        self.second_window = Second_window(self)
        
        # FINISH MAIN WINDOW AND SHOW INITIAL SCREEN
        self.central_widget.addWidget(self.main_window)
        self.central_widget.addWidget(self.second_window)
        self.setCentralWidget(self.central_widget)
        self.current_window = self.main_window
    def b1_handler(self, to_window):
        if to_window == 'second window':
            self.current_window.hide()
            self.second_window.show()
            self.current_window = self.second_window
        elif to_window == 'main window':
            self.current_window.hide()
            self.main_window.show()
            self.current_window = self.main_window
            
    def b2_handler(self):
        pass
    def b3_handler(self):
        pass
    def b4_handler(self):
        pass
    def b5_handler(self):
        pass

class Second_window(QtWidgets.QWidget):
    def __init__(self, parent):
        super().__init__()
        self.parent = parent
        # Create grid
        self.settings = {'grid': {'row': [5,0,0,0,1], 'column': [1,3,1,1]}}
        self.grid = QtWidgets.QGridLayout()        
        self.grid.setVerticalSpacing(20)
        for row, stretch in enumerate(self.settings['grid']['row']):
            self.grid.setRowStretch(row, stretch)
        for column, stretch in enumerate(self.settings['grid']['column']):
            self.grid.setColumnStretch(column, stretch)
        
        # CREATE WIDGETS ON PAGE
        self.b1 = QtWidgets.QPushButton("Button 1")
        self.b1.clicked.connect(self.b1_handler)
        self.b2 = QtWidgets.QPushButton("Button 2")
        self.b2.clicked.connect(self.b2_handler)
        self.b3 = QtWidgets.QPushButton("Button 3")
        self.b3.clicked.connect(self.b3_handler)
        self.b4 = QtWidgets.QPushButton("Button 4")
        self.b4.clicked.connect(self.b4_handler)
        self.b5 = QtWidgets.QPushButton("Button 5")
        self.b5.clicked.connect(self.b5_handler)
        
        self.grid.addWidget(self.b1, 1, 1)
        self.grid.addWidget(self.b2, 1, 2)
        self.grid.addWidget(self.b3, 2, 1)
        self.grid.addWidget(self.b4, 3, 1)
        self.grid.addWidget(self.b5, 4 ,3)
        
        # SET LAYOUT
        self.setLayout(self.grid)
    def b1_handler(self):
        pass 
    def b2_handler(self):
        pass
    def b3_handler(self):
        pass
    def b4_handler(self):
        pass
    def b5_handler(self):
        self.parent.b1_handler('main window')

def main():
    app = QtWidgets.QApplication(sys.argv)
    App = mainWindow()
    App.show()
    # sys.exit(app.exec_())
    currentExitCode = app.exec_()

if __name__ == '__main__':
    main()

使用这段代码，我的 windows 看起来像这样：

主要window:

第二个window:

从主要 window，我使用按钮 1 导航到第二个 window。从第二个 window，我使用按钮 5 导航回主 window。我有什么地方没看懂吗？

Answer 1

强制显示添加到 QStackedWidget 的小部件不是显示它们的正确方法，因为堆叠布局不会收到有关更改的通知，也无法正确中继调整大小事件。

要在小部件之间切换，您必须使用 class 提供的功能，如 QStackedWidget 的主要文档中所述：

The index of the widget that is shown on screen is given by currentIndex() and can be changed using setCurrentIndex(). In a similar manner, the currently shown widget can be retrieved using the currentWidget() function, and altered using the setCurrentWidget() function.

更改为：

    def b1_handler(self, to_window):
        if to_window == 'second window':
            self.central_widget.setCurrentWidget(self.second_window)
        elif to_window == 'main window':
            self.central_widget.setCurrentWidget(self.main_window)

您也不需要对当前页面的引用，因为 currentWidget() 已经动态提供了。

为什么我的第二个 window 有不同的布局？

Why does my second window have a different layout?

python

window

pyqt5