Hiding rows in QTableView seems to be slow

stoeltze

Hi,

I am using QTableView for handling a table with up to 600,000 rows. Displaying the table and sorting it works well.
However, in my interactive environment, I need to rapidly hide/show rows depending on the row index. For a smaller
number of rows (~3000) this works perfectly fast but for 600,000 rows it is terribly slow. As a solution, I tried:
@
qtableview->setUpdatesEnabled(false);
<showRow(...)/hide row(...)>
qtableview->setUpdatesEnabled(true);
@
However, this didn't help.

Any other idea is deeply appreciated.

Best Regards,
Steffen

Edit: Please use @ tags to highlight code; Andre

Eddy

Have a look at Qsortfilterproxymodel.

stoeltze

Thank you very much for the quick reply. I had a look at Qsortfilterproxymodel. I understand now how to use regular expressions to filter rows with respect to the contents of (a) specific field(s). However, I want to filter the rows with respect to their index which is not stored in any field. It just exists implicitly. For example, hide rows 1-5, 10-100, and 500-2000 and show the rest. Could you please provide a hint on how to use Qsortfilterproxymodel for that purpose.

Thank you very much.
Steffen

loladiro

Have a look at "filterAcceptsRow()":http://doc.qt.nokia.com/4.7/qsortfilterproxymodel.html#filterAcceptsRow

Eddy

Your index is just a column in your table ,you should be able to filter on using filteracceptsrow.

stoeltze

Thanks for the helpful suggestions. I guess, I derive my own class from Qsortfilterproxymodel. Then, I overwrite the method filteracceptsrow. In my method, I check whether "int source_row" shall be shown or hidden based on a boolean array (size = number of rows) I already have and I return true or false, respectively. Once the boolean array in my interactive application changes, I have to call invalidateFilter() on my QSortFilterProxyModel. Am I right?

Steffen

loladiro

Yes, you are.

stoeltze

The procedure I described above works very well. Thanks a lot to Eddy and loladiro. Just one thing I would like to add is that instead of calling "invalidateFilter()" on the custom QSortFilterProxyModel, one should call "invalidate()" which is considerably faster. I don't know why...

Steffen