python - 如何动态添加/删除元素中的元素？

Question

这是我的代码。我试图使其在您更改下拉框时，它将动态显示更多或更少的 QLineEdits 用于输入。这只是最新的测试迭代

import sys
from PyQt5.QtWidgets import (QWidget, QPushButton, QLineEdit,
    QInputDialog, QApplication, QComboBox, QFrame)

import numpy as np


class GUI(QWidget):

    def __init__(self):
        super().__init__()

        self.initgui()

    def initgui(self):
        #
        # Set up GUI 
        #
        self.setGeometry(100, 100, 400, 400)
        self.move(300, 300)
        combobox = QComboBox(self)
        for i in range(1, 10, 1):
            combobox.addItem(str(i + 1))
        combobox.activated[str].connect(self.comboboxchanged)
        self.setWindowTitle("Testing Easy Setup")
        self.show()

    def comboboxchanged(self, text):
        frame = QWidget(self)
        frame.hide()
        for num in range(0, int(text), 1):
            QLineEdit(frame).move(60, num * 19)
        frame.show()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    gui = GUI()
    sys.exit(app.exec_())

Answer 1

问题是，当您将父级传递给小部件时，它会被放置在相对于父级的 0, 0 位置，在您的情况下 QFrame 位于 QComboBox 因为两者都位于 0, 0 位置。正确的做法是使用布局。另一方面，您必须在为其添加新小部件之前消除小部件，我们创建了一个消除这些项目的函数。

import sys
from PyQt5.QtWidgets import *

def clearLayout(lay):
    while lay.count() > 0:
        item = lay.takeAt(0)
        widget = item.widget()
        if widget:
            widget.deleteLater()
        del item


class GUI(QWidget):
    def __init__(self):
        super().__init__()
        self.initgui()

    def initgui(self):
        lay = QHBoxLayout(self)
        vlay1 = QVBoxLayout()
        combobox = QComboBox(self)
        combobox.addItems([str(i) for i in range(2, 11)])
        vlay1.addWidget(combobox)
        vlay1.addItem(QSpacerItem(20, 245, QSizePolicy.Minimum, QSizePolicy.Expanding))

        self.vlay2 = QVBoxLayout()
        lay.addLayout(vlay1)
        lay.addLayout(self.vlay2)
        self.comboboxchanged(combobox.currentText())
        combobox.activated[str].connect(self.comboboxchanged)
        self.setWindowTitle("Testing Easy Setup")
        self.show()

    def comboboxchanged(self, text):
        clearLayout(self.vlay2)
        for num in range(0, int(text)):
            self.vlay2.addWidget(QLineEdit(self))
        self.vlay2.addItem(QSpacerItem(20, 245, QSizePolicy.Minimum, QSizePolicy.Expanding))

if __name__ == '__main__':
    app = QApplication(sys.argv)
    gui = GUI()
    sys.exit(app.exec_())