EchoMode的显示效果

import sys
from PyQt5.QtWidgets import QApplication, QLineEdit, QWidget, QFormLayout

class lineEditDemo(QWidget):
    def __init__(self):
        super().__init__()
        self.setWindowTitle('QLineEdit 例子')

        flo = QFormLayout()
        pNormalLineEdit = QLineEdit()
        pNoEchoLineEdit = QLineEdit()
        pPasswordLineEdit = QLineEdit()
        pPasswordEchoOnEditLineEdit = QLineEdit()

        flo.addRow("Normal", pNormalLineEdit)
        flo.addRow("NoEcho", pNoEchoLineEdit)
        flo.addRow("Password", pPasswordLineEdit)
        flo.addRow("PasswordEchoOnEdit", pPasswordEchoOnEditLineEdit)

        pNormalLineEdit.setPlaceholderText("Normal")
        pNoEchoLineEdit.setPlaceholderText("NoEcho")
        pPasswordLineEdit.setPlaceholderText("Password")
        pPasswordEchoOnEditLineEdit.setPlaceholderText("PasswordEchoOnEdit")

        # 设置显示效果
        pNormalLineEdit.setEchoMode(QLineEdit.Normal)
        pNoEchoLineEdit.setEchoMode(QLineEdit.NoEcho)
        pPasswordLineEdit.setEchoMode(QLineEdit.Password)
        pPasswordEchoOnEditLineEdit.setEchoMode(QLineEdit.PasswordEchoOnEdit)

        self.setLayout(flo)

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