Pixelator example for PySide2

[alom]

I'm trying to recreate the Pixelator example for PySide2
https://doc.qt.io/qtforpython/overviews/qtwidgets-itemviews-pixelator-example.html#pixelator-example

Unfortunately something is broken and I'm not getting errors nor and pixel painted. If some one can take a look at the code below and help out that would be very much appreciated.
Thanks

from PySide2 import QtGui, QtCore, QtWidgets


class ImageModel(QtCore.QAbstractTableModel):
    def __init__(self, parent=None):
        super(ImageModel, self).__init__(parent)
        self.model_image = QtGui.QImage('art_image.jpeg') # you will have to replace this

    def rowCount(self, *args, **kwargs):
        return self.model_image.height()

    def columnCount(self, *args, **kwargs):
        return self.model_image.width()

    def data(self, index, role):
        if not index.isValid() or role != QtCore.Qt.DisplayRole:
            return None
        return QtGui.qGray(self.model_image.pixel(index.column(), index.row()))

    def headerData(self, section, orientation, role):
        if role == QtCore.Qt.SizeHintRole:
            return QtCore.QSize(1,1)



class PixelDelegate(QtWidgets.QAbstractItemDelegate):
    def __init__(self, parent=None):
        super(PixelDelegate, self).__init__(parent)
        self.pixel_size = 12

    def paint(self, painter, option, index):
        #if option.state and QtWidgets.QStyle.State_Selected:
         #   painter.fillRect(option.rect, option.palette.highlight())

        size = min(option.rect.width(), option.rect.height())
        brightness = int(index.model().data(index, QtCore.Qt.DisplayRole))
        radius = (size/2.0) - (brightness/255.0 * size/2.0)
        if radius == 0.0:
            return

        painter.save()
        painter.setRenderHint(QtGui.QPainter.Antialiasing, True)
        painter.setPen(QtCore.Qt.NoPen)

        #if option.state and QtWidgets.QStyle.State_Selected:
          #  painter.setBrush(option.palette.highlightedText())
     
        painter.setBrush(QtGui.QBrush(QtCore.Qt.black))
        painter.drawEllipse(QtCore.QRectF(option.rect.x() + option.rect.width() / 2 - radius,
                                       option.rect.y() + option.rect.height() / 2 - radius,
                                       2 * radius, 2 * radius))
        painter.restore()

    def sizeHint(self, option, index):
        return QtCore.QSize(self.pixel_size, self.pixel_size)

    def setPixelSize(self, size):
        self.pixel_size = size


class MainWindow(QtWidgets.QMainWindow):
    def __init__(self):
        super(MainWindow, self).__init__()

        self.model = ImageModel(self)

        centralWidget = QtWidgets.QWidget()

        self.view = QtWidgets.QTableView()
        self.view.setShowGrid(False)
        self.view.horizontalHeader().hide()
        self.view.verticalHeader().hide()
        self.view.horizontalHeader().setMinimumSectionSize(1)
        self.view.verticalHeader().setMinimumSectionSize(1)
        self.view.horizontalHeader().setDefaultSectionSize(4)
        self.view.verticalHeader().setDefaultSectionSize(4)
        self.view.setModel(self.model)

        delegate = PixelDelegate(self)
        self.view.setItemDelegate(delegate)

        mainLayout = QtWidgets.QVBoxLayout()
        mainLayout.addWidget(self.view)
        centralWidget.setLayout(mainLayout)

        self.setCentralWidget(centralWidget)
        self.setWindowTitle("Pixelator")
        self.resize(self.model.columnCount(), self.model.rowCount())

    def updateView(self):
        self.view.resizeColumnsToContents()
        self.view.resizeRowsToContents()


if __name__ == '__main__':
    import sys

    app = QtWidgets.QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())

[JonB]

@alom
Probably completely irrelevant, I haven't looked at the example, but why is your painter.restore() in an else and not correctly paired with the painter.save()? And the drawEllipse() is also else-only? This is Python! Isn't the if else just supposed to be for picking the brush?

[alom]

Ah, Thanks! I had an incorrect indent with :

painter.drawEllipse(QtCore.QRectF(option.rect.x() + option.rect.width() / 2 - radius,
                                   option.rect.y() + option.rect.height() / 2 - radius,
                                   2 * radius, 2 * radius))
painter.restore()

Looks like i had to add code below to correctly set my cell size :

self.view.horizontalHeader().setDefaultSectionSize(4)
self.view.verticalHeader().setDefaultSectionSize(4)

Yeah, I was just trying to match what the example had,
I got rid of that unnecessary "else" ...also not why we need to manage the option.state and QtWidgets.QStyle.State_Selected ?
i remove that and was able to get the black and white image as expected.

Thanks so much!

[JonB]

@alom said in Pixelator example for PySide2:

I had an incorrect indent with :

Indeed! And being my non-favorite language of Python, that was the consequence of those few extra whitespaces :)