WindowSystemMenuHint strange bug

[Engelard]

Hi everybody. I just added new fresh .ui file with class which inherits QDialog for extra window of my main project. Add in ui some layout and labels, it looks as it should, everything ok on the following screenshot:

But when i try to remove that unnecessary MenuHint(question mark) like that:

myNewDialog->setWindowFlags(Qt::WindowSystemMenuHint);

Or. By adding such thing in to constructor of that child dialog:

this->setWindowFlags(Qt::WindowSystemMenuHint);

The window will start looking, i would say, strange:

The code in constructor of my main class:

myNewDialog = new FinalResult(this);   //class of child window
myNewDialog->show();

[Engelard]

Why that stuff even enabled by default...

[Engelard]

Maybe anybody knows another way to hide that button?

[aha_1980]

@Engelard isn't that ...HelpButtonHint?

which type of widget is your dialog? it may be the platform defaiult to show it.

[Engelard]

@aha_1980 said in WindowSystemMenuHint strange bug:

which type of widget is your dialog?

QDialog

[mrjj]

Hi
The reason for the odd look is due to you remove all its flags
setWindowFlags(Qt::WindowSystemMenuHint);
Now ONLY WindowSystemMenuHint is set. not Dialog and all the others it needs.
You need to do
setWindowFlags(windowFlags() & ~Qt::WindowSystemMenuHint);
which takes the current flags and bitwise disable only hint.

[Engelard]

@mrjj

Very good stuff. But.

1. as i understand, it set it from windowFlags() which comes from parent, it do totally no effect if i would try set it up from it's own flags:

myNewDialog->windowFlags()

2. As it appliable only from parent(QMainWindow), it adds maximize and minimize hints, maximize is unnecessary, so i tried to remove it, but it only disable it, not hide:

myNewDialog->setWindowFlags(windowFlags() & (~Qt::WindowSystemMenuHint & ~Qt::WindowMaximizeButtonHint));

[mrjj]

@Engelard
Oh, must be from dialog :)

myNewDialog->setWindowFlags(myNewDialog->windowFlags() & (~Qt::WindowSystemMenuHint & ~Qt::WindowMaximizeButtonHint));

[mrjj]

Not all combinations works all types of windows.

[Engelard]

@mrjj i tried at first from my object(child dialog), not working, tried, can't understand why.

[mrjj]

Hi
I tried

CustomDialog::CustomDialog(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::CustomDialog)
{
    ui->setupUi(this);
    setWindowFlags(Qt::WindowSystemMenuHint | Qt::WindowTitleHint | Qt::WindowCloseButtonHint);
}

[Engelard]

Lol i figure it out, with little help of Qt documentation and imagination:

resultsWindow = new FinalResult(this);
Qt::WindowFlags flags = 0;
flags = Qt::Dialog;

resultsWindow->setWindowFlags(flags |= Qt::WindowSystemMenuHint); // question mark removed, but close button now disabled
resultsWindow->setWindowFlag(Qt::WindowCloseButtonHint, true);

[Engelard]

@mrjj said in WindowSystemMenuHint strange bug:

Hi
I tried

I try that stuff long ago, no efforts of doing that attempts from the constructor of child QDialog were paid...

[mrjj]

@Engelard
ok, odd. worked for my dialog.