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 <code&gt;QHeaderView&lt;/code&gt;, but the alternative to subclass "QSortFilterProxyModel&quot;:http://doc.qt.nokia.com/stable/qsortfilterproxymodel.html and reimplement the <code&gt;filterAcceptsColumn()</code&gt; method also works well.

Column hiding using QHeaderView

All multi-column views provide access to a "QHeaderView&quot;: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&gt;

class FSMProxy : public QSortFilterProxyModel
{
Q_OBJECT

public:
FSMProxy(QObject *parent);

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

fsmproxy.cpp

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

bool FSMProxy::filterAcceptsColumn(int source_column, const QModelIndex &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);