[Solved] A way to save QTreeWidget to file

chamoda

Hello,

I'm trying to save QTreeWidget to file and load it another time. I wrote this code but it didnt work.

Save..

@ QList<QTreeWidgetItem *> myList;
for(int i = 0; i < treeWidget->topLevelItemCount(); i++)
{
myList << treeWidget->takeTopLevelItem(i);
}

    QDataStream outStream(&file);
    outStream.setVersion(QDataStream::Qt_4_7);
    outStream << myList;@

Load..

@QDataStream inStream(&file);
inStream.setVersion(QDataStream::Qt_4_7);
inStream >> myList; // error
treeWidget->addTopLevelItems(myList);@

Is there any simple function or way to do this?

thanks

jazzycamel

"This":http://doc.qt.digia.com/qt/datastreamformat.html page contains a list of all the Qt types/objects that are serializable, QTreeWidgetItem isn't one of them I'm afraid. AFAIK there is no built in way to directly stream a QTreeWidget to a file. I think you'll have to traverse the data structure and save it in a suitably structured file format (JSON or XML for example).

chamoda

thanks for your reply jazzycamel. Any example code to do it with XML?

TheBadger

I use a Qt Library called "Qtilities":http://www.qtilities.org/. It has its own way of "building trees":http://www.qtilities.org/docs/master/page_tree_structures.html with Observers

I has its own "observer widget":http://www.qtilities.org/docs/master/page_observer_widgets.html that can then be used to display this tree.

Using the built in functions, this tree can then saved to an XML or binary file. Perhaps you can also use this library as is or look at the code of how it is done.

There is a section in the docs on "saving and loading the tree to XML":http://www.qtilities.org/docs/master/page_tree_structures.html#tree_xml that will do all the work for you.

chamoda

Thanks Badger. I didn't know about Qtilities before.

also I found a way to do it with QStringList because my structure was simple..

Like this

@
QList<QStringList> myList;

        QDataStream inStream(&file);
        inStream.setVersion(QDataStream::Qt_4_7);
        inStream >> myList;
         for(int i = 0; i < myList.size(); i++)
        {
         QTreeWidgetItem *item = new QTreeWidgetItem(myList.at(i));
         treeWidget->addTopLevelItem(item);
        }

@

Thanks all for replying. Problem solved!