CODEWITHSUNDEEP
qtpyqtpyqt5
Michael Herrmann
Michael Herrmann

Reputation: 5003

QTableView performance

I'm using a QTableView with PyQt5. As soon as I start to display a few thousand rows, the performance is abysmal. I tried the suggestions from this question but the Qt Graphics View framework and QTreeView are not viable options for me. Does anybody have other ideas for optimizing the performance of a QTableView?

Upvotes: 1

Views: 581

Answers (1)

danesjoe
danesjoe

Reputation: 36

You can mirror the effect of QTreeView's setUniformRowHeights by implementing sizeHintForRow:

class UniformRowHeights(QTableView):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self._row_height = None
    def sizeHintForRow(self, row):
        model = self.model()
        if row < 0 or row >= model.rowCount():
            # Mirror super implementation.
            return -1
        return self.get_row_height()
    def get_row_height(self):
        if self._row_height is None:
            self._row_height = max(self._get_cell_heights())
        return self._row_height
    def changeEvent(self, event):
        # This for instance happens when the style sheet changed. It may affect
        # the calculated row height. So invalidate:
        self._row_height = None
        super().changeEvent(event)
    def _get_cell_heights(self, row=0):
        self.ensurePolished()
        option = self.viewOptions()
        model = self.model()
        for column in range(model.columnCount()):
            index = model.index(row, column)
            delegate = self.itemDelegate(index)
            if delegate:
                yield delegate.sizeHint(option, index).height()

Upvotes: 2

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