How to remove minimize button from QMessageBox

Kucchan

Hi,

I am using Qt Creator in RaspberryPi3(Linux) , When I create a message box Minimize Button is displayed .

How to remove Minimize button ?
As another method,
Is there a way to ignore it even if I press the minimize button?

The development environment is as follows.

RaspberryPi3 , Raspbian GNU/Linux 9.1 (stretch)
Qt Creator 4.2.0、Qt 5.7.1 (GCC 6.2.1 20161124, 32 bit)

jsulm

@Kucchan See http://doc.qt.io/qt-5/qwidget.html#windowFlags-prop and Qt::WindowMinimizeButtonHint

Kucchan

Dear jsulm
Thank you for your comment.
But I can not solve the problem.

I tried the following contents, but I could hide the minimize button in Windows OS, but in RaspberryPi 3 (Linux) I could not hide the minimize button.
http://doc.qt.io/qt-5/qtwidgets-widgets-windowflags-example.html

How can I hide the minimize button on RaspberryPi 3?

JonB

@Kucchan
You may not be able to. It depends on whether your OS/desktop allows this, Qt is using platform's native windows, Windows does, there is no guarantee that Pi/Ubuntu/GNOME or whatever you are using supports removing just the minimize button.

For example, from the Qt docs:

In Linux with KDE this code make a window without an close and minimize and maximize buttons in title bar.

setWindowFlags( Qt::Dialog | Qt::WindowTitleHint );

dream_captain

QMessageBox box.
box.setText("randomText");
box.setWindowFlags(box.windowFlags() & (~Qt::WindowMinimizeButtonHint));

Should do the trick, but as @JNBarchan mentioned earlier it's platform dependent.

JonB

@dream_captain
Since he says:

I tried the following contents, but I could hide the minimize button in Windows OS, but in RaspberryPi 3 (Linux) I could not hide the minimize button.

I presume that indicates he has the right code, it works under Windows but not under Linux....

Kucchan

Thank you everyone.

I tried '~ Qt :: WindowMinimizeButtonHint' but it was useless.
It seems impossible to remove Minimize button.
So,Please tell me how to not minimize the window by clicking the minimize button.

SGaist

Hi,

Can you show the code you are currently using for your message box ?

Kucchan

Dear SGaist

It is the code that challenged to remove minimize button of MainWindow and QMessageBox.

MsgBox.pro

QT += core gui
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = MsgBox
TEMPLATE = app
DEFINES += QT_DEPRECATED_WARNINGS
SOURCES += main.cpp
mainwindow.cpp
HEADERS += mainwindow.h
FORMS += mainwindow.ui

main.cpp

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

int main(int argc, char *argv[])
{
Qt::WindowFlags flags;

QApplication a(argc, argv);
MainWindow w;
flags = w.windowFlags();
flags = flags & ~Qt::WindowMinimizeButtonHint;
w.setWindowFlags(flags);
w.show();
return a.exec();

}

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QMessageBox>

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

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

void MainWindow::on_pushButton_clicked()
{
QMessageBox msgBox(this);
msgBox.setText(tr("MessageText"));
msgBox.setWindowTitle(tr("Title"));
msgBox.setIcon(QMessageBox::Critical);
msgBox.setWindowFlags(Qt::Window | Qt::Dialog | Qt::MSWindowsFixedSizeDialogHint | Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowCloseButtonHint);
msgBox.exec();
}

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 slots:
void on_pushButton_clicked();

private:
Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

mainwindow.ui

Only QpushButton is placed in MainWindow.

dream_captain

@Kucchan
I was able to add and then remove minimize button from QMessageBox on my Linux Mint by setting Qt::Window flag first and then removing Qt::WindowMinimizeButtonHint

QMessageBox msgBox;
msgBox.setText("MessageText");
msgBox.setWindowTitle("Title");
msgBox.setWindowFlags(Qt::Window );     // add minimize button
msgBox.setWindowFlags(msgBox.windowFlags()&(~Qt::WindowMinimizeButtonHint)); // remove minimize button
msgBox.setIcon(QMessageBox::Critical);
msgBox.exec();

Give it a try. Set Qt::Window and then remove Qt::WindowMinimizeButtonHint

Kucchan

Dear dream_captain

Thank you for your comment.
But It was useless in the RaspberryPi3.

If the minimize button can be remove, without
' ~Qt::WindowMinimizeButtonHint:WindowMinimizeButtonHint '.
(WindowsOS and Ubuntu)

RaspberryPi3 seems to be unique.

dream_captain

@Kucchan
I don't think that you can inherit from QMessageBox and just ignore minimize event, since it's controlled by window manager.

Does QDialog come with minimize button by default on your rasp?

Kucchan

@dream_captain

Does QDialog come with minimize button by default on your rasp?

I tried QDialog on RaspberryPi3 and the minimize button was displayed.
(Not change WindowFlags.WindowFlags is default value)

QDialog can’t remove minimize button by changing WindowFlags.

jsulm

@Kucchan I think this is not a problem with Qt but with window manager used. As far as I know Raspbian uses its own (Pixel?).

Kucchan

Is there no way?
Do I need to give up?

dream_captain

@Kucchan
You can try an ugly workaround: derive from QDialog and play around Qt::FramelessWindowHint to hide top buttons completely. Then add QPushButton on form and create a connection connect(ui->closeButton, &QPushButton::clicked, this, &QDialog::accept);' to imitate QMessageBox behavior.

Kucchan

@dream_captain

Thank you for your comment.
I will make a message box by QDialog.

Ulises Galgo

@Kucchan Too late with the answer, but this works for me on a RPi3 with Raspbian:

msgBox.setWindowFlags( ( Qt::Window | Qt::CustomizeWindowHint ) &~
   ( Qt::WindowTitleHint | Qt::WindowSystemMenuHint | 
     Qt::WindowMinimizeButtonHint | Qt::WindowCloseButtonHint ) );

someone else could be looking for the same answer as I did.