Update QTableView after hiding columns

goetz

Why not use a proxy model (based on "QSortFilterProxyModel":http://doc.qt.nokia.com/stable/qsortfilterproxymodel.html) like in this "wiki article":http://developer.qt.nokia.com/wiki/Filter_Columns_in_a_QFileSystemModel

And don't forget to let the model emit signals (columnAdde/Remove etc.) afterwards to have the view catch up the changes.

giesbert

you needn't emit signals if you just filter out rows. There are callback for hiding rows/columns in QSortFilterProxyModel: "filterAcceptsColumn":http://doc.qt.nokia.com/latest/qsortfilterproxymodel.html#filterAcceptsColumn and "filterAcceptsRow":http://doc.qt.nokia.com/latest/qsortfilterproxymodel.html#filterAcceptsRow

Also see the "example in the description of QSortFilterProxyModel":http://doc.qt.nokia.com/latest/qsortfilterproxymodel.html#filtering

goetz

Yep. But if the filter rules change after the view has finished displaying items, you must inform the view of the change. Fortunately the Trolls have provided us with slot "invalidateFilter() ":http://doc.qt.nokia.com/latest/qsortfilterproxymodel.html#invalidateFilter for this :-)

js_dev

Thanks so far.

I will have a look at the proxy model next week and will also try to unhide the hidden columns before I hide them again.

js_dev

Ok, if I do this

// unhide all hidden columns
int rows = myDataTableModel()->rowCount();
for(int i=0; i<rows; i++)
{
 ui.mySimDataTableView->setColumnHidden(i, false);
}

before

ui.mySimDataTableView->setModel(myDataTableModel);

everythink is fine.

Thank you :-)

giesbert

[quote author="js_dev" date="1296216104"]Thanks so far.

I will have a look at the proxy model next week and will also try to unhide the hidden columns before I hide them again.[/quote]

If you use the proxy model approach, the setColumnHidden of the view is not needed anymore.

giesbert

Ok, if I do this
// unhide all hidden columns
int rows = myDataTableModel()->rowCount();
for(int i=0; i<rows; i++)
{
ui.mySimDataTableView->setColumnHidden(i, false);
}
before

ui.mySimDataTableView->setModel(myDataTableModel);

everythink is fine.

Thank you :-)[/quote]

What is a bit strange:

you iterate over rowCount and call setColumnHidden
This does not fit!

js_dev

Oh man - I mixed up rows and columns again :-(
Sorry for the confuision.

It must look like this:

// unhide all hidden columns
int cols = myDataTableModel()->columnCount();
for(int i=0; i<cols; i++)
{
 ui.mySimDataTableView->setColumnHidden(i, false);
}

ui.mySimDataTableView->setModel(myDataTableModel());

js_dev

I found another (maybe easier) way to unhide all the previously hidden columns.

If I resize the columns to content after hiding the columns I can get rid of the loop I posted above and the table view shows all the columns I want to see.

Do it like this:

if (stuff.exec(s))
{
 while(stuff.next())
 {
  hide = stuff.value(1).toInt() == 0;
  index = myDataTableModel();->fieldIndex(stuff.value(0).toString());
  if(index >= 0)
  {
   ui.mySimDataTableView->setColumnHidden(index, hide);
  }
 }
}
// This will resize the columns to content and also unhide all previously hidden columns
ui.mySimDataTableView->resizeColumnsToContents();

giesbert

As this is not a described behavior, you should take care that it might change in future...