Qt FullScreen on Startup

Question

I want to start an application on fullscreen (MacOS 10.8.x, Qt 5.1.1, C++) depending on the settings:

main.cpp

#include "MainWindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.showFullScreen();

    return a.exec();
}

MainWindow.cpp

#include "MainWindow.h"
#include "ui_MainWindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
}

MainWindow::~MainWindow()
{
    delete ui;
}

MainWindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

The settings comportment is perfect, works like a charm. But this->showFullScreen() does something very ugly :

1. Display the window in fullscreen
2. Display the window in normal size in the center
3. Scale the window to fullscreen

I can provide a video if needed. How to avoid this?

edit :

add the video here, made a better snippet without the settings

Answer 1

I already faced this problem and a very nice solution was to delay the fullscreen switch by one second (using a QTimer):

QTimer::singleShot(0, this, SLOT(showFullScreen()));