Check if directory is empty - qt

Question

I'm trying to check if a directory is empty.
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
QDir Dir("/home/highlander/Desktop/dir");
if(Dir.count() == 0)
{
QMessageBox::information(this,"Directory is empty","Empty!!!");
}
}
Whats the right way to check it, excluding . and ..?

Answer 1

Well, I got the way to do it :)
if(QDir("/home/highlander/Desktop/dir").entryInfoList(QDir::NoDotAndDotDot|QDir::AllEntries).count() == 0)
{
QMessageBox::information(this,"Directory is empty","Empty!!!");
}

Answer 2

Since Qt 5.9 there is bool QDir::isEmpty(...), which is preferable as it is clearer and faster, see docs:
Equivalent to count() == 0 with filters QDir::AllEntries | QDir::NoDotAndDotDot, but faster as it just checks whether the directory contains at least one entry.

Answer 3

As Kirinyale pointed out, hidden and system files (like socket files)
are not counted in highlander141's answer.
To count these as well, consider the following method:
bool dirIsEmpty(const QDir& _dir)
{
QFileInfoList infoList = _dir.entryInfoList(QDir::AllEntries | QDir::System | QDir::NoDotAndDotDot | QDir::Hidden );
return infoList.isEmpty();
}

Answer 4

This is one way of doing it.
#include <QCoreApplication>
#include <QDir>
#include <QDebug>
#include <QDesktopServices>
int main(int argc, char *argv[])
{
QCoreApplication app(argc,argv);
QDir dir(QDesktopServices::storageLocation(QDesktopServices::DesktopLocation));
QStringList list = dir.entryList();
int count;
for(int x=0;x<list.count(); x++)
{
if(list.at(x) != "." && list.at(x) != "..")
{
count++;
}
}
qDebug() << "This directory has " << count << " files in it.";
return 0;
}

Answer 5

Or you could just check with;
if(dir.count()<3){
... //empty dir
}