[Qt-interest] Blocking signals from / to MVC components.

[Stephen Kelly]

MARTIN Pierre wrote:

> Ok guys, i think i have found a "not-too-dirty" solution, tell me if you
> something which can go wrong with this idea. Lets say my implementation of
> my QSqlTableModel derived class looks like this:
> 
> bool	setData		(QModelIndex const &i, QVariant const &v, int
> r=Qt::EditRole) { // First make sure that the column for which data is
> being set is the blob, and the signals are not blocked already.
> bool		block	= 
i.column()==MyModel::BinaryBlobNotShownInTablesAndViews &&
> !signalsBlocked() // Block if needed.
> if (block)				blockSignals	(true);
> // Set the data, get the success flag.
> bool		ok		= QSqlTableModel::setData(i, v, r);
> // Unblock signals if blocked by this method.
> if (block)				blockSignals	(false);
> return		ok;
> }
> 
> What do you think? i made a draft of it, and i don't loose selection
> anymore :)
> 
> Thank you guys,
> Pierre.

After unblocking the signals you should emit dataChanged. That's assuming 
the row doesn't get moved around by sorting in the query or anything when 
the data is updated.