python--pyQt5 pyside6 中 下拉列表框(QComboBox)

self.Settings_UI.pushButton_7.clicked.connect(self.getItem)  
def getItem(self):
    items = ('OTU0', 'OTU1', 'OTU2')
    # 返回两个值，第一个item代表用户选择的值，ok代表用户是否按下了取消
    item, ok = QInputDialog.getItem(self, '请选择', '', items)
    if ok and item:
        self.Settings_UI.lineEdit.setText(item)
QInputDialog.getItem：选择选项的下拉列表
 QInputDialog.getText：获取输入的文本内容
 QInputDialog.getInt：获取输入数字的计时器
import sys
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5.QtGui import *
class QInputDialogDemo(QWidget):
    def __init__(self):
        super(QInputDialogDemo, self).__init__()
        self.initUI()
    def initUI(self):
        self.setWindowTitle("输入对话框")
        layout = QFormLayout()
        self.button1 = QPushButton("获取列表中的选项")
        self.button1.clicked.connect(self.getItem)
        self.lineEdit1 = QLineEdit()
        layout.addRow(self.button1, self.lineEdit1)
        self.button2 = QPushButton("获取字符串")
        self.button2.clicked.connect(self.getText)
        self.lineEdit2 = QLineEdit()
        layout.addRow(self.button2, self.lineEdit2)
        self.button3 = QPushButton("获取整数")
        self.button3.clicked.connect(self.getInt)
        self.lineEdit3 = QLineEdit()
        layout.addRow(self.button3, self.lineEdit3)
        self.setLayout(layout)
    def getItem(self):
        items = ('C', 'C++', 'Ruby', 'Python', 'Java')
        # 返回两个值，第一个item代表用户选择的值，ok代表用户是否按下了取消
        item, ok = QInputDialog.getItem(self, "请选择编程语言", "语言列表", items)
        if ok and item:
            self.lineEdit1.setText(item)
    def getText(self):
        text, ok = QInputDialog.getText(self, "文本输入框", "输入姓名")
        if ok and text:
            self.lineEdit2.setText(text)
    def getInt(self):
        num, ok  = QInputDialog.getInt(self, "整数输入框", "输入数字")
        if ok and num:
            self.lineEdit3.setText(str(num))
if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = QInputDialogDemo()
    main.show()
    sys.exit(app.exec_())
import sys
from PySide6.QtWidgets import QApplication, QMainWindow, QLineEdit
class MainWindow(QMainWindow):
    def __init__(self):
        super(MainWindow, self).__init__()
        self.setWindowTitle("My App")
        widget = QLineEdit()
        '''设置输入内容最大长度'''
        widget.setMaxLength(10)
        '''设置文本框提示'''
        widget.setPlaceholderText("Enter your text")
        '''设置为只读模式'''
        # widget.setReadOnly(True)
        widget.returnPressed.connect(self.return_pressed)
        widget.selectionChanged.connect(self.selection_changed)  # 只要改变了，这个信号就会被触发
        widget.textChanged.connect(self.text_changed)  # 当修改文本内容时，这个信号就会被触发
        widget.textEdited.connect(self.text_edited)  # 当编辑文本结束时，这个信号就会被触发
        self.setCentralWidget(widget)
    def return_pressed(self):
        print("按了Enter键！")
        self.centralWidget().setText("BOOM!")
    def selection_changed(self):
        print("选中了文本！")
        print(self.centralWidget().selectedText())
    def text_changed(self, s):
        print("文本改变了！")
        print(s)
    def text_edited(self, s):
        print("文本被编辑了！")
        print(s)
if __name__ == '__main__':
    app = QApplication(sys.argv)  # 初始化
    win = MainWindow()  # 初始化界面并展示
    win.show()
    app.exec()