Filter Columns in a QFileSystemModel

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How to Filter Columns in a QFileSystemModel

Sometimes one does not want to display all the columns of a "QFileSystemModel":http://doc.qt.nokia.com/stable/qfilesystemmodel.html, like discussed in "this forum thread":http://developer.qt.nokia.com/forums/viewthread/3114/.

This can be achieved in two ways, either by hiding the columns in the view, by using a specialized proxy model. The easiest way is to hide the columns using the

QHeaderView

, but the alternative to subclass "QSortFilterProxyModel":http://doc.qt.nokia.com/stable/qsortfilterproxymodel.html and reimplement the

filterAcceptsColumn()

method also works well.

Column hiding using QHeaderView

All multi-column views provide access to a "QHeaderView":http://doc.qt.nokia.com/stable/qheaderview.html . This is the widget that provides the headers above the columns of data, and allows the user to resize those columns, or click the headers to trigger a sorting order. You can also use this widget to hide columns in your view.

//hide the third and fourth column, note that the column numbers are 0-based
QHeaderView* hHeader = m_theTableview->horizontalHeader();
hHeader->hideSection(2);
hHeader->hideSection(3);

The alternative method of using a custom proxy model is outlined below.

Column hiding using QSortFilterProxyModel

Be aware that the column count is 0-based and that it is hard coded.

==== fsmproxy.h

#include <QSortFilterProxyModel> ====

class FSMProxy : public QSortFilterProxyModel
{
 Q_OBJECT

public:
 FSMProxy(QObject *parent);

protected:
 bool filterAcceptsColumn(int source_column, const QModelIndex &amp;source_parent) const;
};

==== fsmproxy.cpp

FSMProxy::FSMProxy(QObject *parent)
 : QSortFilterProxyModel(parent)
{
} ====

bool FSMProxy::filterAcceptsColumn(int source_column, const QModelIndex &amp;source_parent) const
{
 Q_UNUSED(source_parent)

    // adjust the columns you want to filter out here
    // return false for those that will be hidden
 if(source_column  2 || source_column  3)
 return false;
 return true;
}

==== Usage

    QFileSystemModel *fsm = new QFileSystemModel(this);
    FSMProxy *proxy = new FSMProxy(this);
    proxy->setSourceModel(fsm);
    treeView->setModel(proxy);

====