import sys
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5.QtGui import *

"""
下面示例揭示了，当关键字绑定的控件出现的时候，快捷键才管用，
绑定的控件没有出现的时候快捷键无效
"""


class Demo1(QMainWindow):
    def __init__(self):
        super().__init__()
        form_layout = QFormLayout()
        self.text_edit = QTextEdit()
        shortcut_show_msg = QShortcut(QKeySequence(Qt.CTRL + Qt.Key_M), self.text_edit)
        shortcut_show_msg.activated.connect(lambda: print('你好'))
        button = QPushButton("显示/隐藏")
        button.clicked.connect(self.show_or_hide)
        form_layout.addRow("文本行", self.text_edit)
        form_layout.addWidget(QTextEdit())
        form_layout.addWidget(button)
        widget = QWidget()
        widget.setLayout(form_layout)
        self.setCentralWidget(widget)

    def show_or_hide(self):
        if self.text_edit.isVisible():
            self.text_edit.setVisible(False)
        else:
            self.text_edit.setVisible(True)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = Demo1()
    window.show()
    sys.exit(app.exec_())