14 QAbstractTableModel example

QAbstractTableModel example

This QAbstractTableModel example shows how you can define a custom Qt model to display tabular data.

The data is a table of famous scientists. In Python, it can be written as follows:

headers = ["Scientist name", "Birthdate", "Contribution"]
rows =    [("Newton", "1643-01-04", "Classical mechanics"),
           ("Einstein", "1879-03-14", "Relativity"),
           ("Darwin", "1809-02-12", "Evolution")]

To make Qt display these data in a table, we need to answer the following questions:

1. How many rows are there?
2. How many columns?
3. What's the value of each cell?
4. What are the (column) headers?

We do this by subclassing QAbstractTableModel. This lets us answer each of the above questions by implementing a corresponding method:

class TableModel(QAbstractTableModel):
    def rowCount(self, parent):
        # How many rows are there?
        return len(rows)
    def columnCount(self, parent):
        # How many columns?
        return len(headers)
    def data(self, index, role):
        if role != Qt.DisplayRole:
            return QVariant()
        # What's the value of the cell at the given index?
        return rows[index.row()][index.column()]
    def headerData(self, section, orientation, role:
        if role != Qt.DisplayRole or orientation != Qt.Horizontal:
            return QVariant()
        # What's the header for the given column?
        return headers[section]

Once we have this model, we can instantiate it, connect it to a QTableView and show it in a window:

model = TableModel()
view = QTableView()
view.setModel(model)
view.show()

The full code is in main.py. For instructions how to run it, please see the instructions in the README of this repository.