Basic PyQt Signal Slot Example with PyQT5

gistfile1.txt

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

class MainWindow(QMainWindow):
    onNameEntered = pyqtSignal(str)

    def __init__(self):
        super(MainWindow, self).__init__()
        self.inner = QWidget(self)
        self.inner.setLayout(QVBoxLayout(self))
        self.line_edit = QLineEdit(self)
        self.text_plot = TextPlot(self)
        self.lbl_has_been_clicked = QLabel("Has not been clicked, yet", self)

        self.inner.layout().addWidget(self.line_edit)
        self.inner.layout().addWidget(self.text_plot)
        self.inner.layout().addWidget(self.lbl_has_been_clicked)

        self.setCentralWidget(self.inner)

        # Connecting the Signals and Slots
        self.line_edit.editingFinished.connect(self.parse_name)
        self.onNameEntered.connect(self.text_plot.update_plot)

        # You can also use partial to set the parameter when connecting slots
        self.text_plot.hasBeenClicked.connect(partial(self.on_plot_clicked, "has been clicked"))

        self.show()

    @pyqtSlot()
    def parse_name(self):
        name = self.line_edit.text()
        name = "Input: " + name

        #Emit the Signal to the TextPlot
        self.onNameEntered.emit(name)

    @pyqtSlot(str)
    def on_plot_clicked(self, text):
        self.lbl_has_been_clicked.setText(text)

class TextPlot(QGraphicsView):
    hasBeenClicked = pyqtSignal()

    def __init__(self, parent):
        super(TextPlot, self).__init__(parent)
        self.setScene(QGraphicsScene(self))

    @pyqtSlot(str)
    def update_plot(self, text):
        self.scene().clear()
        for i in range(10):
            itm = self.scene().addText(text)
            itm.setDefaultTextColor(QColor(200,100,100,200))
            itm.setPos(10, i * 20)

    def mousePressEvent(self, event: QMouseEvent):
        self.hasBeenClicked.emit()


# The QT Exception Hook
def my_exception_hook(exctype, value, traceback):
    # Print the error and traceback
    print((exctype, value, traceback))
    # Call the normal Exception hook after
    sys._excepthook(exctype, value, traceback)
    sys.exit(1)

if __name__ == '__main__':
    sys._excepthook = sys.excepthook
    sys.excepthook = my_exception_hook
    app = QApplication(sys.argv)
    main = MainWindow()
    sys.exit(app.exec_())