模式是没有这个信号的，但是我们可以自己创建一个 resized 信号，并在 resizeEvent 方法中 emit.

用 QtDesigner 设计个主窗口，拖了 Horizontal Layout（mainHLayout） 和窗体同一尺寸，三个 pushbutton，分割按钮的4个Horizontal Spacer。就是想改变窗体大小时，可以让按钮可以继续按比例分配空间。

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>800</width>
    <height>600</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <widget class="QWidget" name="horizontalLayoutWidget">
    <property name="geometry">
     <rect>
      <x>0</x>
      <y>0</y>
      <width>801</width>
      <height>571</height>
     </rect>
    </property>
    <layout class="QHBoxLayout" name="mainHLayout">
     <item>
      <spacer name="horizontalSpacer">
       <property name="orientation">
        <enum>Qt::Horizontal</enum>
       </property>
       <property name="sizeHint" stdset="0">
        <size>
         <width>40</width>
         <height>20</height>
        </size>
       </property>
      </spacer>
     </item>
     <item>
      <widget class="QPushButton" name="pushButton_3">
       <property name="text">
        <string>PushButton</string>
       </property>
      </widget>
     </item>
     <item>
      <spacer name="horizontalSpacer_2">
       <property name="orientation">
        <enum>Qt::Horizontal</enum>
       </property>
       <property name="sizeHint" stdset="0">
        <size>
         <width>40</width>
         <height>20</height>
        </size>
       </property>
      </spacer>
     </item>
     <item>
      <widget class="QPushButton" name="pushButton_2">
       <property name="text">
        <string>PushButton</string>
       </property>
      </widget>
     </item>
     <item>
      <spacer name="horizontalSpacer_3">
       <property name="orientation">
        <enum>Qt::Horizontal</enum>
       </property>
       <property name="sizeHint" stdset="0">
        <size>
         <width>40</width>
         <height>20</height>
        </size>
       </property>
      </spacer>
     </item>
     <item>
      <widget class="QPushButton" name="pushButton">
       <property name="text">
        <string>PushButton</string>
       </property>
      </widget>
     </item>
     <item>
      <spacer name="horizontalSpacer_4">
       <property name="orientation">
        <enum>Qt::Horizontal</enum>
       </property>
       <property name="sizeHint" stdset="0">
        <size>
         <width>40</width>
         <height>20</height>
        </size>
       </property>
      </spacer>
     </item>
    </layout>
   </widget>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>

pyuic5 resizeDemo.ui -o resizeDemo.py生成的 Py 文件：

from PyQt5 import QtCore, QtGui, QtWidgets

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.horizontalLayoutWidget = QtWidgets.QWidget(self.centralwidget)
        self.horizontalLayoutWidget.setGeometry(QtCore.QRect(0, 0, 801, 571))
        self.horizontalLayoutWidget.setObjectName("horizontalLayoutWidget")
        self.mainHLayout = QtWidgets.QHBoxLayout(self.horizontalLayoutWidget)
        self.mainHLayout.setContentsMargins(0, 0, 0, 0)
        self.mainHLayout.setObjectName("mainHLayout")
        spacerItem = QtWidgets.QSpacerItem(40, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.mainHLayout.addItem(spacerItem)
        self.pushButton_3 = QtWidgets.QPushButton(self.horizontalLayoutWidget)
        self.pushButton_3.setObjectName("pushButton_3")
        self.mainHLayout.addWidget(self.pushButton_3)
        spacerItem1 = QtWidgets.QSpacerItem(40, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.mainHLayout.addItem(spacerItem1)
        self.pushButton_2 = QtWidgets.QPushButton(self.horizontalLayoutWidget)
        self.pushButton_2.setObjectName("pushButton_2")
        self.mainHLayout.addWidget(self.pushButton_2)
        spacerItem2 = QtWidgets.QSpacerItem(40, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.mainHLayout.addItem(spacerItem2)
        self.pushButton = QtWidgets.QPushButton(self.horizontalLayoutWidget)
        self.pushButton.setObjectName("pushButton")
        self.mainHLayout.addWidget(self.pushButton)
        spacerItem3 = QtWidgets.QSpacerItem(40, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.mainHLayout.addItem(spacerItem3)
        MainWindow.setCentralWidget(self.centralwidget)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.pushButton_3.setText(_translate("MainWindow", "PushButton"))
        self.pushButton_2.setText(_translate("MainWindow", "PushButton"))
        self.pushButton.setText(_translate("MainWindow", "PushButton"))

新建一个入口文件，并引用 resizeDemo.py

from PyQt5 import QtWidgets, QtCore
from resizeDemo import Ui_MainWindow


class Window(QtWidgets.QMainWindow):

    resized = QtCore.pyqtSignal()

    def __init__(self, parent=None):
        super(Window, self).__init__(parent=parent)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)

        self.resized.connect(self.someFunction)

    def resizeEvent(self, event):
        self.resized.emit()

    def someFunction(self):
        windowWidth = self.frameGeometry().width()
        windowHeight = self.frameGeometry().height()
        print("Window width:%d" % windowWidth)
        print("Window height:%d" % windowHeight)
        print(".....")
        # self.ui.horizontalLayoutWidget.resize(windowWidth, windowHeight - 30)
        self.ui.mainHLayout.parent().resize(windowWidth, windowHeight - 30)


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    w = Window()
    w.show()
    sys.exit(app.exec_())

最后修改于 2017-09-12