import sys
from PyQt5 import QtWidgets,QtCore,Qt
from PyQt5.QtWidgets import QApplication, QWidget

class TestWindow(QtWidgets.QWidget):
  def __init__(self):
    super(QtWidgets.QWidget,self).__init__()
    self._createInputWindow()
    self._setMainWindowOptions()

  def _setMainWindowOptions(self):
    self.setFixedSize(4000, 4000)

    self.setWindowFlags(
      QtCore.Qt.ToolTip # comment out this line, then QLineEdits work fine
      | QtCore.Qt.FramelessWindowHint
      | QtCore.Qt.WindowMaximizeButtonHint
      | QtCore.Qt.WindowMinimizeButtonHint
      | QtCore.Qt.WindowFullscreenButtonHint
      | QtCore.Qt.WindowMinMaxButtonsHint
      | QtCore.Qt.WindowCloseButtonHint
      | QtCore.Qt.BypassWindowManagerHint
      | QtCore.Qt.NoDropShadowWindowHint
      | QtCore.Qt.WindowStaysOnTopHint
      | QtCore.Qt.CustomizeWindowHint
      | QtCore.Qt.WindowTitleHint
      | QtCore.Qt.WindowSystemMenuHint
      | QtCore.Qt.WindowOverridesSystemGestures
      | QtCore.Qt.MacWindowToolBarButtonHint
      | QtCore.Qt.NoDropShadowWindowHint
    )
    self.showFullScreen()
    self.setWindowTitle('Test Guard')

  def _createInputWindow(self):
    self.inputWindow = QtWidgets.QWidget(self)
    # declare controls
    headerLabel = QtWidgets.QLabel("Test Guard", self.inputWindow)
    font = headerLabel.font()
    font.setPointSize(72)
    font.setBold(True)
    headerLabel.setFont(font)
    self.m_btnClose = QtWidgets.QPushButton('Close', self.inputWindow)
    self.m_leUserName = QtWidgets.QLineEdit(self.inputWindow)
    self.m_lePassword = QtWidgets.QLineEdit(self.inputWindow)
    self.m_btnSubmit = QtWidgets.QPushButton('Submit', self.inputWindow)
    self.m_lePassword.setEchoMode(QtWidgets.QLineEdit.Password)
    self.m_btnClose.clicked.connect(self.onBtnCloseClick)
    self.m_btnSubmit.clicked.connect(self.onBtnCloseClick)
    # create layout then place controls to the layout
    self.inputWindow.horizontalGroupBox = QtWidgets.QGroupBox(self.inputWindow)
    layout = QtWidgets.QGridLayout(self.inputWindow)
    layout.setColumnStretch(0, 1)
    layout.setColumnStretch(1, 2)
    layout.setColumnStretch(2, 3)
    layout.setColumnStretch(3, 2)
    layout.addWidget(headerLabel, 0, 0, 1, 4)
    layout.addWidget(self.m_btnClose, 1, 1)
    layout.addWidget(QtWidgets.QLabel("User Name:", self.inputWindow), 2, 1)
    layout.addWidget(self.m_leUserName, 2, 2)
    layout.addWidget(QtWidgets.QLabel("Password:", self.inputWindow), 3, 1)
    layout.addWidget(self.m_lePassword, 3, 2)
    layout.addWidget(self.m_btnSubmit, 5, 1)
    self.inputWindow.horizontalGroupBox.setLayout(layout)
    windowLayout = QtWidgets.QVBoxLayout(self.inputWindow)
    windowLayout.addWidget(self.inputWindow.horizontalGroupBox)
    self.inputWindow.setLayout(windowLayout)
    self.inputWindow.setGeometry(0, 0, 800, 400)
    self.inputWindow.move(self.rect().center())

  def onBtnCloseClick(self):
    QtWidgets.qApp.quit()

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