pyqt/model-views/tableview_demo.py

import sys
from datetime import datetime

from PyQt5.QtCore import QAbstractTableModel, Qt
from PyQt5.QtGui import QColor
from PyQt5.QtWidgets import QTableView, QMainWindow, QApplication

COLORS = [
    '#053061', '#2166ac', '#4393c3', '#92c5de', '#d1e5f0', '#f7f7f7',
    '#fddbc7', '#f4a582', '#d6604d', '#b2182b', '#67001f'
]


class TableModel(QAbstractTableModel):

    def __init__(self, data):
        super(TableModel, self).__init__()
        self._data = data

    def data(self, index, role):
        if role == Qt.DecorationRole:
            value = self._data[index.row()][index.column()]
            if isinstance(value, int) or isinstance(value, float):
                value = int(value)

                value = max(-5, value)  # value < -5 becomes -5
                value = min(5, value)  # value > 5 becomes 5
                value = value + 5  # -5 becomes 0, 5 becomes 10

                return QColor(COLORS[value])
        if role == Qt.ForegroundRole:
            value = self._data[index.row()][index.column()]
            if (isinstance(value, int)
                    or isinstance(value, float)) and value < 0:
                return QColor(Qt.red)

        if role == Qt.TextAlignmentRole:
            value = self._data[index.row()][index.column()]
            if isinstance(value, int) or isinstance(value, float):
                # Align right, vertical middle.
                return Qt.AlignVCenter + Qt.AlignRight

        if role == Qt.DisplayRole:
            # See below for the nested-list data structure.
            # .row() indexes into the outer list,
            # .column() indexes into the sub-list
            value = self._data[index.row()][index.column()]

            if isinstance(value, datetime):
                # Here, we use the date's string representation.
                return value.strftime('%Y-%m-%d')
            if isinstance(value, str):
                # Here, we use the date
                return '"%s"' % value
            if isinstance(value, float):
                # Here, we use the date
                return "%.2f" % value
            return value

    def rowCount(self, index):
        # The length of the outer list.
        return len(self._data)

    def columnCount(self, index):
        # The following takes the first sub-list, and returns
        # the length (only works if all rows are an equal length)
        return len(self._data[0])


class MainWindow(QMainWindow):

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

        self.table = QTableView()

        data = [
            [4, 9, 2],
            [1, -1, 'hello'],
            [3.141592653589793, 2.718281828459045, 'world'],
            [3, 3, datetime(2025, 2, 18)],
            [7, 1, -5],
        ]

        self.model = TableModel(data)
        self.table.setModel(self.model)

        self.setCentralWidget(self.table)


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