PyQt draw inside QScrollArea in a QDialog

Question

I am drawing in PyQt5 inside a QDialog box but need to add the ability to scroll as I add to the objects drawn. It seems like the best option maybe to add a QScrollArea widget and draw inside that but I haven't been able to find anything telling me how to do so. I was able to find this question that seems to be on topic, but is for C++ and I don't understand it.

Qt - draw inside QScrollArea in a QDialog

Would someone be able to translate what this means into Python or explain what would be necessary to draw inside a QScrollArea widget or add scroll bars to a QDialog?

Answer 1

Each class has a single responsibility, in this case there must be 2 widgets: the widget where it is drawn and the widget that has the QScrollArea:

from PyQt5 import QtCore, QtGui, QtWidgets

class DrawWidget(QtWidgets.QWidget):
    def __init__(self, *args, **kwargs):
        super(DrawWidget, self).__init__(*args, **kwargs)
        self.setFixedSize(640, 480)

    def paintEvent(self, event):
        painter = QtGui.QPainter(self)
        painter.setRenderHint(QtGui.QPainter.Antialiasing)
        painter.setBrush(QtGui.QBrush(QtCore.Qt.darkMagenta))
        painter.setPen(QtCore.Qt.NoPen)
        path = QtGui.QPainterPath()
        path.addText(QtCore.QPoint(10, 100), QtGui.QFont("Times", 40, QtGui.QFont.Bold), "Stack Overflow and Qt")
        painter.drawPath(path)

class Dialog(QtWidgets.QDialog):
    def __init__(self, parent=None):
        super(Dialog, self).__init__(parent)
        scroll_area = QtWidgets.QScrollArea(widgetResizable=True)
        draw_widget = DrawWidget()
        scroll_area.setWidget(draw_widget)
        lay = QtWidgets.QVBoxLayout(self)
        lay.addWidget(scroll_area)

if __name__ == '__main__':
    import sys
    app = QtWidgets.QApplication(sys.argv)
    w = Dialog()
    w.resize(320, 240)
    w.show()
    sys.exit(app.exec_())