Why does QTableWidgetItem setflags() trigger itemChanged() signal?

[Aaron Kim]

void Dialog::setRowDisable(QTableWidget* table, int row){
    for(int column = 0; column < table->columnCount(); ++column){
        auto item = table->item(row, column);
        item->setFlags(item->flags() & ~Qt::ItemIsEditable);
    }
}

This simple code makes me suffer from segmentation fault derived from infinite loop.

I can not understand this situation because setting flag does not affect the data of QTableWidgetItem.
Is it intended? If so, how can I prevent it from triggering the event?

[mrjj]

Hi
Because you do change the item. :)
Anyway, try
setting

void Dialog::setRowDisable(QTableWidget* table, int row){
   table->blockSignals(true);
    for(int column = 0; column < table->columnCount(); ++column){
        auto item = table->item(row, column);
        item->setFlags(item->flags() & ~Qt::ItemIsEditable);
    }
   table->blockSignals(false);
}

If that works as you want , have a look at
https://doc.qt.io/qt-5/qsignalblocker.html

Its a better way of doing the same.

[Aaron Kim]

@mrjj Oh, there is a blockSignal function in Qt. I was struggling with implementing it myself ;) Thanks!

[mrjj]

@Aaron-Kim
yep :)
qsignalblocker is a special scope handling class that ensure u dont miss
a blockSignals(false); if code in between can bail out due to error.