空白 PyQt5 程序

Question

我正在尝试使用 PyQt5 创建一个简单的 GUI，但是每当我运行程序时。它显示的只是一个空白窗口。如何让按钮或 QLineEdit 等元素实际出现在窗口中？

任何指针都将不胜感激，因为我正在尝试创建一个可以接受用户输入（在本例中为徽章和票号）然后在将信息显示为输出之前查询数据库以获取管属性和数量的应用程序。

from PyQt5 import QtCore, QtWidgets

class Ui_MainWindow(object):

    def __init__(self):
        self.title = 'Tube Bender UI'
        self.description = QtWidgets.QLabel('New Order Available')
        self.badge = QtWidgets.QLineEdit()
        self.ticket = QtWidgets.QLineEdit()
        self.tubes = 0

    def setupUi(self, MainWindow):

        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 641)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(MainWindow.sizePolicy().hasHeightForWidth())
        MainWindow.setSizePolicy(sizePolicy)
        MainWindow.setMaximumSize(QtCore.QSize(800, 641))

        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setMinimumSize(QtCore.QSize(800, 641))
        self.centralwidget.setMaximumSize(QtCore.QSize(800, 641))
        self.centralwidget.setObjectName("centralwidget")
        self.horizontalLayoutWidget = QtWidgets.QWidget(self.centralwidget)
        self.horizontalLayoutWidget.setGeometry(QtCore.QRect(0, 320, 801, 641))

        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.horizontalLayoutWidget.sizePolicy().hasHeightForWidth())

    #tubes = 0

    def coil_id(self):
        QtWidgets.QLineEdit(self)
        return self.ticket

    def page_description(self):
        QtWidgets.QLineEdit(self)
        return self.description

    def page_title(self):
        QtWidgets.QLineEdit(self)
        return self.title

    def badge_id(self):
        QtWidgets.QLineEdit(self)
        return self.badge

    def tube_count(self):
        QtWidgets.QLineEdit(self)
        print(self.tubes)


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()
    MainPage = QtWidgets.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show())
    sys.exit(app.exec_()

Answer 1

看看这个小例子，尽量做到最简单。还有更多要学习的东西和更多好的实践，不仅仅是通过这样的一切，但无论如何，这里是：

import sys
from PyQt5.QtWidgets import QApplication
from PyQt5.QtWidgets import QHBoxLayout
from PyQt5.QtWidgets import QLabel
from PyQt5.QtWidgets import QLineEdit
from PyQt5.QtWidgets import QMainWindow
from PyQt5.QtWidgets import QVBoxLayout
from PyQt5.QtWidgets import QWidget


class MainWindow(QMainWindow):

    layout_main = None
    central_widget = None
    lbl_name = None
    lbl_value = None
    input_name = None
    input_value = None

    def __init__(self):
        super(MainWindow, self).__init__()
        self.init_ui()

    def init_ui(self):
        #variables
        self.layout_main = QVBoxLayout()
        self.layout_labels = QHBoxLayout()
        self.layout_inputs = QHBoxLayout()
        self.central_widget = QWidget()
        self.lbl_name = QLabel("name")
        self.lbl_name.setFixedSize(100,50)
        self.lbl_value = QLabel("Value")
        self.lbl_value.setFixedSize(100, 50)
        self.input_name = QLineEdit()
        self.input_name.setFixedSize(100, 50)
        self.input_value = QLineEdit()
        self.input_value.setFixedSize(100, 50)
        #style
        self.layout_main.setContentsMargins(10, 10, 10, 10)
        self.setMinimumSize(250,100)
        #adding objects
        self.layout_labels.addWidget(self.lbl_name)
        self.layout_labels.addWidget(self.lbl_value)
        self.layout_main.addLayout(self.layout_labels)
        self.layout_inputs.addWidget(self.input_name)
        self.layout_inputs.addWidget(self.input_value)
        self.layout_main.addLayout(self.layout_inputs)

        self.central_widget.setLayout(self.layout_main)
        self.setCentralWidget(self.central_widget)

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

你会看到，稍后你将不得不重写许多继承自 qt 类的类，并根据你的需要一一进行个性化。只是一个提示“）