QFileDialog that accepts a single file or a single directory - c++

Question

Is it possible to show a QFileDialog where the user can select a file or a directory, either one?
QFileDialog::getOpenFileName() accepts only files, while QFileDialog::getExistingDirectory() is directories-only, but I need to show a file dialog that can accept both a file or a directory (it makes sense for my program). QFileDialog::​Options didn't have anything promising.

Answer 1

QFileDialog currently does not support this. I think the main problem for you here is that the FileMode is not a Q_FLAGS and the values are not power of 2, either, and so, you cannot write this to solve this issue.
setFileMode(QFileDialog::Directory|QFileDialog::ExistingFiles)
To solve this, you would need quite a bit of fiddling, e.g.:
Override the open button click operation.
Get the "treeview" indices properly for both files and directories.
My attempt below demonstrates the former, but I did not really go as far as solving the second because that seems to involve some more fiddling with the selection model.
main.cpp
#include <QFileDialog>
#include <QApplication>
#include <QWidget>
#include <QTreeWidget>
#include <QPushButton>
#include <QStringList>
#include <QModelIndex>
#include <QDir>
#include <QDebug>
class FileDialog : public QFileDialog
{
Q_OBJECT
public:
explicit FileDialog(QWidget *parent = Q_NULLPTR)
: QFileDialog(parent)
{
setOption(QFileDialog::DontUseNativeDialog);
setFileMode(QFileDialog::Directory);
// setFileMode(QFileDialog::ExistingFiles);
for (auto *pushButton : findChildren<QPushButton*>()) {
qDebug() << pushButton->text();
if (pushButton->text() == "&Open" || pushButton->text() == "&Choose") {
openButton = pushButton;
break;
}
}
disconnect(openButton, SIGNAL(clicked(bool)));
connect(openButton, &QPushButton::clicked, this, &FileDialog::openClicked);
treeView = findChild<QTreeView*>();
}
QStringList selected() const
{
return selectedFilePaths;
}
public slots:
void openClicked()
{
selectedFilePaths.clear();
qDebug() << treeView->selectionModel()->selection();
for (const auto& modelIndex : treeView->selectionModel()->selectedIndexes()) {
qDebug() << modelIndex.column();
if (modelIndex.column() == 0)
selectedFilePaths.append(directory().absolutePath() + modelIndex.data().toString());
}
emit filesSelected(selectedFilePaths);
hide();
qDebug() << selectedFilePaths;
}
private:
QTreeView *treeView;
QPushButton *openButton;
QStringList selectedFilePaths;
};
#include "main.moc"
int main(int argc, char **argv)
{
QApplication application(argc, argv);
FileDialog fileDialog;
fileDialog.show();
return application.exec();
}
main.pro
TEMPLATE = app
TARGET = main
QT += widgets
CONFIG += c++11
SOURCES += main.cpp
Build and Run
qmake && make && ./main

Answer 2

Quite old question but I think I have a simpler solution than most for the lazy ones.
You can connect the signal currentChanged of QFileDialog with a function that dynamically changes the fileMode.
//header
class my_main_win:public QMainWindow
{
private:
QFileDialog file_dialog;
}
//constructor
my_main_win(QWidget * parent):QMainWindow(parent)
{
connect(&file_dialog,QFileDialog::currentChanged,this,[&](const QString & str)
{
QFileInfo info(str);
if(info.isFile())
file_dialog.setFileMode(QFileDialog::ExistingFile);
else if(info.isDir())
file_dialog.setFileMode(QFileDialog::Directory);
});
}
And then simply call file_dialog as you would.
if(file_dialog.exec()){
QStringList dir_names=file_dialog.selectedFiles():
}

Answer 3

What worked for me was to use:
file_dialog.setProxyModel(nullptr);
as suggested here, or
class FileFilterProxyModel : public QSortFilterProxyModel
{
protected:
virtual bool filterAcceptsRow(int sourceRow, const QModelIndex& sourceParent) const
{
QFileSystemModel* fileModel = qobject_cast<QFileSystemModel*>(sourceModel());
return (fileModel!=NULL && fileModel->isDir(sourceModel()->index(sourceRow, 0, sourceParent))) || QSortFilterProxyModel::filterAcceptsRow(sourceRow, sourceParent);
}
};
...
FileFilterProxyModel* proxyModel = new FileFilterProxyModel;
file_dialog.setProxyModel(proxyModel);
as suggested here, or
class FileDialog : public QFileDialog
{
Q_OBJECT
public:
explicit FileDialog(QWidget *parent = Q_NULLPTR)
: QFileDialog(parent)
{
m_btnOpen = NULL;
m_listView = NULL;
m_treeView = NULL;
m_selectedFiles.clear();
this->setOption(QFileDialog::DontUseNativeDialog, true);
this->setFileMode(QFileDialog::Directory);
QList<QPushButton*> btns = this->findChildren<QPushButton*>();
for (int i = 0; i < btns.size(); ++i) {
QString text = btns[i]->text();
if (text.toLower().contains("open") || text.toLower().contains("choose"))
{
m_btnOpen = btns[i];
break;
}
}
if (!m_btnOpen) return;
m_btnOpen->installEventFilter(this);
//connect(m_btnOpen, SIGNAL(changed()), this, SLOT(btnChanged()))
m_btnOpen->disconnect(SIGNAL(clicked()));
connect(m_btnOpen, SIGNAL(clicked()), this, SLOT(chooseClicked()));
m_listView = findChild<QListView*>("listView");
if (m_listView)
m_listView->setSelectionMode(QAbstractItemView::ExtendedSelection);
m_treeView = findChild<QTreeView*>();
if (m_treeView)
m_treeView->setSelectionMode(QAbstractItemView::ExtendedSelection);
}
QStringList selectedFiles()
{
return m_selectedFiles;
}
bool eventFilter( QObject* watched, QEvent* event )
{
QPushButton *btn = qobject_cast<QPushButton*>(watched);
if (btn)
{
if(event->type()==QEvent::EnabledChange) {
if (!btn->isEnabled())
btn->setEnabled(true);
}
}
return QWidget::eventFilter(watched, event);
}
public slots:
void chooseClicked()
{
QModelIndexList indexList = m_listView->selectionModel()->selectedIndexes();
foreach (QModelIndex index, indexList)
{
if (index.column()== 0)
m_selectedFiles.append(this->directory().absolutePath() + "/" + index.data().toString());
}
QDialog::accept();
}
private:
QListView *m_listView;
QTreeView *m_treeView;
QPushButton *m_btnOpen;
QStringList m_selectedFiles;
};
as suggested here. Credits for the original authors and me.

Answer 4

Connect to the currentChanged signal and then set the file mode to the currently selected item (directory or file). This is a Python3 implementation:
class GroupFileObjectDialog(QFileDialog):
def __init__(self, parent):
super().__init__(parent)
self.setOption(QFileDialog.DontUseNativeDialog)
self.setFileMode(QFileDialog.Directory)
self.currentChanged.connect(self._selected)
def _selected(self,name):
if os.path.isdir(name):
self.setFileMode(QFileDialog.Directory)
else:
self.setFileMode(QFileDialog.ExistingFile)
Tested on PyQt 5.14 running on linux / Ubuntu18.04.