def usage(self):
"""Show usage of the program.
"""
msg = QMessageBox(self.parent)
msg.setWindowTitle("Usage")
#msg.setTitle("Usage of this GUI")
text = QLabel(MessageText.usage_text)
msg.setIcon(QMessageBox.Information)
scroll = QScrollArea(msg)
scroll.setWidgetResizable(True)
grid = msg.findChild(QGridLayout)
text.setWordWrap(True)
scroll.setWidget(text)
scroll.setMinimumSize(800, 400)
scroll.setStyleSheet("""
border: 1.5px solid black;
padding: 15px;
""")
grid.addWidget(scroll, 0, 1)
msg.exec_()
