How can you set header labels for QTableView columns?

Question

I’m working on a Python GUI application with PyQt5 which has a QTableView for showing data.

Here is the code:

import sys

from PyQt5 import QtWidgets, QtCore
from PyQt5.QtCore import Qt


class DataModel(QtCore.QAbstractTableModel):
    def __init__(self):
        super().__init__()
        self.data = []

    def data(self, index, role):
        if role == Qt.DisplayRole:
            return self.data[index.row()][index.column()]

    def rowCount(self, index):
        return len(self.data)

    def columnCount(self, index):
        return len(self.data[0])


class MainWindow(UI.UserInterface):
    def __init__(self):
        super().__init__()
        self.model = DataModel()
        self.load()
        self.TableView.setModel(self.model)
        self.TableView.resizeColumnsToContents()
        self.TableView.horizontalHeader().setStretchLastSection(True)

    def load(self):
        try:
            self.model.data = [(1, '2020-01-10 00:00:00', 'KANIA', 'HENRYK', 4219)]
        except Exception:
            pass


if __name__ == "__main__":
    app = QtWidgets.QApplication(sys.argv)
    window = MainWindow()
    window.show()
    app.exec_()

The class UI.UserInterface is in separate module. It has the QWidgets of the interface and layout QWidgets. One of them is QTableView.

I can't seem to find a way to set the header labels for the QTableView.

I looked for different solutions (some of them below) but none of them worked:

https://doc.qt.io/qt-5/sql-presenting.html (this one is written in C++. I don't quite understand it)

Answer 1

You must implement headerData():

class DataModel(QtCore.QAbstractTableModel):
    # ...
    def headerData(self, section, orientation, role=QtCore.Qt.DisplayRole):
        if orientation == QtCore.Qt.Horizontal and role == QtCore.Qt.DisplayRole:
            return 'Column {}'.format(section + 1)
        return super().headerData(section, orientation, role)

Obviously you can set your own labels even with a simple list containing the labels you want to show.

Note that you should be very careful with naming new attributes to subclasses as they might already exist.
Most importantly, you should not overwrite self.data.

Answer 2

Override headerData method of QTableAbstractModel to set Columns and Rows name

def headerData(self, section: int, orientation: PySide6.QtCore.Qt.Orientation, role: int = ...):
    #for setting columns name
    if orientation == Qt.Horizontal and role == Qt.DisplayRole:
        return f"Column {section + 1}"
    #for setting rows name
    if orientation == Qt.Vertical and role == Qt.DisplayRole:
        return f"Row {section + 1}"

Working code:

import sys
import requests

import PySide6
from PySide6.QtWidgets import QTableView, QWidget, QApplication, QGridLayout, QHeaderView
from PySide6.QtCore import Qt, QAbstractTableModel
from PySide6.QtGui import QColor, QIcon, QPixmap

from datetime import datetime


class MagicIcon():
    def __init__(self, link):
        self.link = link
        self.icon = QIcon()
        try:
            response = requests.get(self.link)
            pixmap = QPixmap()
            pixmap.loadFromData(response.content)
            self.icon = QIcon(pixmap)
        except:
            pass


class TableModel(QAbstractTableModel):

    def headerData(self, section: int, orientation: PySide6.QtCore.Qt.Orientation, role: int = ...):
        if orientation == Qt.Horizontal and role == Qt.DisplayRole:
            # return f"Column {section + 1}"
            return self.columns[section]
        if orientation == Qt.Vertical and role == Qt.DisplayRole:
            return f"{section + 1}"

    def __init__(self, _data):
        self.columns = ["Account", "Investment", "KYC", "Investment Date"]
        # super().__init__(self)
        super(TableModel, self).__init__()
        self._data = _data
        self.calendarLink = "https://img.icons8.com/fluency/48/000000/windows-calendar.png"
        self.dollarLink = "https://img.icons8.com/external-vitaliy-gorbachev-lineal-color-vitaly-gorbachev/40/000000/external-dollar-currency-vitaliy-gorbachev-lineal-color-vitaly-gorbachev-1.png"
        self.analysis = "https://img.icons8.com/external-flatarticons-blue-flatarticons/65/000000/external-analysis-digital-marketing-flatarticons-blue-flatarticons-1.png"
        self.bug = "https://img.icons8.com/offices/30/000000/bug.png"
        self.account = "https://img.icons8.com/plumpy/24/000000/edit-administrator.png"
        self.approvedLink = "https://img.icons8.com/external-bearicons-flat-bearicons/40/000000/external-approved-approved-and-rejected-bearicons-flat-bearicons-9.png"
        self.rejectedLink = "https://img.icons8.com/external-bearicons-flat-bearicons/40/000000/external-rejected-approved-and-rejected-bearicons-flat-bearicons-11.png"
        self.naLink = "https://img.icons8.com/color/48/000000/not-applicable.png"

        self.calendarIcon = MagicIcon(self.calendarLink).icon
        self.accountIcon = MagicIcon(self.account).icon
        self.dollarIcon = MagicIcon(self.dollarLink).icon
        self.approvedIcon = MagicIcon(self.approvedLink).icon
        self.rejectedIcon = MagicIcon(self.rejectedLink).icon
        self.naIcon = MagicIcon(self.naLink).icon

    def data(self, index, role):
        if role == Qt.DisplayRole:
            value = self._data[index.row()][index.column()]
            if isinstance(value, datetime):
                return value.strftime("%Y-%m-%d")
            if isinstance(value, float):
                return f"{value:.2f}"
            return value
        if role == Qt.TextAlignmentRole:
            return Qt.AlignHCenter + Qt.AlignVCenter

        if role == Qt.BackgroundRole:
            return QColor("#adcdff") if index.row() % 2 == 0 else QColor("#d8ffc2")

        if role == Qt.DecorationRole:
            value = self._data[index.row()][index.column()]
            
            if value is None:
                return self.naIcon
            if isinstance(value, datetime):
                return self.calendarIcon
            if index.column() == 0:
                return self.accountIcon
            if index.column() == 1:
                return self.dollarIcon
            if index.column() == 2:
                if value == True:
                    return self.approvedIcon
                elif value == False:
                    return self.rejectedIcon
                return self.naIcon

    def rowCount(self, index):
        return len(self._data)

    def columnCount(self, index):
        return len(self._data[0])


class MainWindow(QWidget):
    def __init__(self):
        # super().__init__()
        super(MainWindow, self).__init__()
        self.resizeEvent = self.onResize
        self.table = QTableView()
        
        self.setWindowIcon(MagicIcon(
            "https://img.icons8.com/external-flatarticons-blue-flatarticons/65/000000/external-analysis-digital-marketing-flatarticons-blue-flatarticons-1.png"
        ).icon)

        self.table.horizontalHeader().setSectionResizeMode(QHeaderView.Stretch)
        # self.table.setSizeAdjustPolicy(QHeaderView.AdjustIgnored)
        # self.table.verticalHeader().setSectionResizeMode(QHeaderView.Stretch)
        data = [
            ["Andrew Mike", 15.255, True, datetime(2022, 1, 5)],
            ["Eliza Petterson", 353.555, False, datetime(2020, 1, 5)],
            ["Joseph Samuel", 123, None, datetime(2020, 1, 15)],
            ["Nita Singh", 266, True, datetime(2022, 2, 7)],
            ["Rahul Chakrabarti", 102, True, datetime(2019, 10, 15)],
        ]
        self.model = TableModel(data)
        self.table.setModel(self.model)
        self.header = self.table.horizontalHeader()
        # self.header.setSectionResizeMode(0, QHeaderView.Stretch)
        # self.header.setSectionResizeMode(1, QHeaderView.)
        # self.header.setSectionResizeMode(2, QHeaderView.ResizeToContents)
        self.layout = QGridLayout()
        self.layout.addWidget(self.table, 0, 0)
        self.setLayout(self.layout)

    def onResize(self, event):
        # print('old', event.oldSize(), 'new', event.size())
        # super(MainWindow, self).resizeEvent(event)
        pass


if __name__ == "__main__":
    app = QApplication(sys.argv)
    wid = MainWindow()
    wid.show()
    sys.exit(app.exec())