custom QAbstractTableModel class updating QTableView

[anda_skoa]

When opening the dialog I've connected the dataChanged() signal to a slot which shows a debug message in the console. the connect() call returns true in debug.

And you are not emitting it in any method that you are executing.

How is a signal supposed to happen if its emit is not on a code path that is being executed?

The commented lines (reloading the model) didn't make any difference.

Of course that didn't make any difference, there is not a single emit dataChanged() in your load method.
The load method resets the model, if you want to trigger on that connect to modelReset().

The button just increments a number when it's clicked and writes it to the file:

No call on the model, so how would the model emit a signal?

Cheers,
_