如何在不创建填充按钮的情况下填充 QHBoxLayout 以对齐多个 QGroupBox？

Question

我得到了这个布局：

但我想将第一个文本框与第二个文本框对齐，如下所示：

但不必创建一个无用的按钮来填充空间。

这是我想出的最小示例代码：

import sys

from PyQt5 import QtGui
from PyQt5 import QtWidgets

from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *

def main():
    app = QtWidgets.QApplication(sys.argv)
    programWindow = ProgramWindow()

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


class ProgramWindow(QtWidgets.QMainWindow):

    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.setup_main_window()

        self.first_input_text()
        self.second_input_text()

        self.set_window_layout()

    def setup_main_window(self):
        self.resize( 800, 600 )
        self.centralwidget = QWidget()
        self.setCentralWidget( self.centralwidget )

    def first_input_text(self):
        self.textEditWidget1 = QPlainTextEdit( self )
        self.startSimulationButton1 = QPushButton( "Start Simulation" )
        self.startSimulationButtonDumb = QPushButton( "Start Simulation fillingg" )

        verticalInnerLayout = QVBoxLayout()
        verticalInnerLayout.addWidget( self.startSimulationButton1 )
        verticalInnerLayout.addWidget( self.startSimulationButtonDumb )

        horizontalInnerLayout = QHBoxLayout()
        horizontalInnerLayout.addLayout( verticalInnerLayout )
        horizontalInnerLayout.addWidget( self.textEditWidget1 )

        self.groupBox1 = QGroupBox( "First Group" )
        self.groupBox1.setLayout( horizontalInnerLayout )

    def second_input_text(self):
        self.textEditWidget2 = QPlainTextEdit( self )
        self.startSimulationButton2 = QPushButton( "Start Simulation bigger" )

        verticalInnerLayout = QVBoxLayout()
        verticalInnerLayout.addWidget( self.startSimulationButton2 )

        horizontalInnerLayout = QHBoxLayout()
        horizontalInnerLayout.addLayout( verticalInnerLayout )
        horizontalInnerLayout.addWidget( self.textEditWidget2 )

        self.groupBox2 = QGroupBox( "Second Group" )
        self.groupBox2.setLayout( horizontalInnerLayout )

    def set_window_layout(self):
        main_vertical_layout = QVBoxLayout( self.centralwidget )
        main_vertical_layout.addWidget( self.groupBox1 )
        main_vertical_layout.addWidget( self.groupBox2 )


if __name__ == "__main__":
    main()

Answer 1

QWidget.setMinimumWidth(minw) 此属性保存小部件的最小宽度（以像素为单位）。

试试看：

import sys

from PyQt5 import QtGui
from PyQt5 import QtWidgets

from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *

def main():
    app = QtWidgets.QApplication(sys.argv)
    programWindow = ProgramWindow()

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


class ProgramWindow(QtWidgets.QMainWindow):

    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.setup_main_window()

        self.first_input_text()
        self.second_input_text()

        self.set_window_layout()

    def setup_main_window(self):
        self.resize( 800, 600 )
        self.centralwidget = QWidget()
        self.setCentralWidget( self.centralwidget )

    def first_input_text(self):
        self.textEditWidget1 = QPlainTextEdit( self )
        self.startSimulationButton1 = QPushButton( "Start Simulation" )
        self.startSimulationButton1.setMinimumWidth(150) #+
        #self.startSimulationButtonDumb = QPushButton( "Start Simulation fillingg" )

        verticalInnerLayout = QVBoxLayout()
        verticalInnerLayout.addWidget( self.startSimulationButton1 )
        #verticalInnerLayout.addWidget( self.startSimulationButtonDumb )

        horizontalInnerLayout = QHBoxLayout()
        horizontalInnerLayout.addLayout( verticalInnerLayout )
        horizontalInnerLayout.addWidget( self.textEditWidget1 )

        self.groupBox1 = QGroupBox( "First Group" )
        self.groupBox1.setLayout( horizontalInnerLayout )

    def second_input_text(self):
        self.textEditWidget2 = QPlainTextEdit( self )
        self.startSimulationButton2 = QPushButton( "Start Simulation bigger" )
        self.startSimulationButton2.setMinimumWidth(150) # +

        verticalInnerLayout = QVBoxLayout()
        verticalInnerLayout.addWidget( self.startSimulationButton2 )

        horizontalInnerLayout = QHBoxLayout()
        horizontalInnerLayout.addLayout( verticalInnerLayout )
        horizontalInnerLayout.addWidget( self.textEditWidget2 )

        self.groupBox2 = QGroupBox( "Second Group" )
        self.groupBox2.setLayout( horizontalInnerLayout )

    def set_window_layout(self):
        main_vertical_layout = QVBoxLayout( self.centralwidget )
        main_vertical_layout.addWidget( self.groupBox1 )
        main_vertical_layout.addWidget( self.groupBox2 )


if __name__ == "__main__":
    main()

Answer 2

我做到了：

使用此代码：

import sys

from PyQt5 import QtGui
from PyQt5 import QtWidgets

from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *


def main():
    app = QtWidgets.QApplication(sys.argv)
    programWindow = ProgramWindow()

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


class ProgramWindow(QtWidgets.QMainWindow):

    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.setup_main_window()
        self.first_input_text()
        self.second_input_text()
        self.set_window_layout()

    def setup_main_window(self):
        self.largestFirstCollumn = 0
        self.resize( 800, 600 )

        self.centralwidget = QWidget()
        self.setCentralWidget( self.centralwidget )

    def first_input_text(self):
        self.textEditWidget1 = QPlainTextEdit( self )
        self.startSimulationButton1 = QPushButton( "Start Simulation" )

        self.firstVerticalInnerLayout = QVBoxLayout()
        self.firstVerticalInnerLayout.addWidget( self.startSimulationButton1 )

        self.firstHorizontalInnerLayout = QHBoxLayout()
        self.firstHorizontalInnerLayout.addLayout( self.firstVerticalInnerLayout )
        self.firstHorizontalInnerLayout.addWidget( self.textEditWidget1 )

        self.groupBox1 = QGroupBox( "First Group" )
        self.groupBox1.setLayout( self.firstHorizontalInnerLayout )
        self.get_minimum_width( self.firstVerticalInnerLayout )

    def second_input_text(self):
        self.textEditWidget2 = QPlainTextEdit( self )
        self.startSimulationButton2 = QPushButton( "Start Simulation bigger" )

        self.secondVerticalInnerLayout = QVBoxLayout()
        self.secondVerticalInnerLayout.addWidget( self.startSimulationButton2 )

        self.secondHorizontalInnerLayout = QHBoxLayout()
        self.secondHorizontalInnerLayout.addLayout( self.secondVerticalInnerLayout )
        self.secondHorizontalInnerLayout.addWidget( self.textEditWidget2 )

        self.groupBox2 = QGroupBox( "Second Group" )
        self.groupBox2.setLayout( self.secondHorizontalInnerLayout )
        self.get_minimum_width( self.secondVerticalInnerLayout )

    def get_minimum_width(self, target_layout):
        # https://stackoverflow.com/questions/4963220/how-to-preview-sizes-of-widgets-in-layout-before-a-show
        # How to preview sizes of widgets in layout before a show()?
        target_layout.update()
        target_layout.activate()

        geometry = target_layout.geometry()
        print("%sx%s" % ( geometry.width(), geometry.height() ) )

        if geometry.width() > self.largestFirstCollumn:
            self.largestFirstCollumn = geometry.width()

    def set_minimum_width(self, left_layout, right_layout):
        right_layout.update()
        right_layout.activate()

        geometry = right_layout.geometry()
        print( "%sx%s - %s, %s" % ( geometry.width(), geometry.height(), self.largestFirstCollumn, geometry.width() ) )
        left_layout.setSpacing( 10 + self.largestFirstCollumn - geometry.width() )

    def set_window_layout(self):
        main_vertical_layout = QVBoxLayout( self.centralwidget )
        main_vertical_layout.addWidget( self.groupBox1 )
        main_vertical_layout.addWidget( self.groupBox2 )

        self.set_minimum_width( self.firstHorizontalInnerLayout, self.firstVerticalInnerLayout)
        self.set_minimum_width( self.secondHorizontalInnerLayout, self.secondVerticalInnerLayout)


if __name__ == "__main__":
    main()

---

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