Making a QMessageBox with a single centered button

[Dummie1138]

Hi. I'm trying to make a QMessageBox with a single centered button. Other posts suggest that this is impossible, and this is how I've done it so far, not with a QMessageBox but with a QDialog, QVBoxLayout, QLayout and QPushButton.

        QDialog *needMoreSelections = new QDialog(this);
        needMoreSelections->setWindowTitle("Not enough inputs!");
        //Set size of QDialog.
        needMoreSelections->setFixedSize(450, 200);
        needMoreSelections->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Minimum);
        QVBoxLayout *nMSLayout = new QVBoxLayout;   //nMS is need more selection. Sorry bout the confusion.
        nMSLayout->setAlignment(Qt::AlignCenter);
        needMoreSelections->setLayout(nMSLayout);
        //Add a QLabel
        QLabel *nMSText = new QLabel(this);
        nMSLayout->addWidget(nMSText);
        nMSText->setText("At least 4 inputs have to be selected, you miserable waste of processing power!");
        nMSText->setText("At least 4 inputs are required!");
        nMSText->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Minimum);
        nMSText->setWordWrap(true);
        nMSText->setAlignment(Qt::AlignCenter);
        needMoreSelections->setStyleSheet("font: 20px; color: navy; border: none; outline: none;"); //Need to set to center and add image.
        //Add a QButton
        QPushButton *nMSOk = new QPushButton("Ok", this);
        nMSOk->setStyleSheet("QPushButton {border: 2px solid #8f8f91;border-radius: 9px;background-color: QLinearGradient(x1: 0, y1: 0, x2: 0, y2: 1,stop: 0 #f6f7fa, stop: 1 #dadbde);font: 25px;outline: none; width: 128px; height: 128px;}"
            "QPushButton:pressed {background-color: QLinearGradient(x1: 0, y1: 0, x2: 0, y2: 1,stop: 0 #dadbde, stop: 1 #f6f7fa) }");
        nMSLayout->addWidget(nMSOk);

        connect(nMSOk, SIGNAL(clicked()), needMoreSelections, SLOT(close()));
        needMoreSelections->exec();

I am trying to consolidate this code into fewer pieces to improve readability. According to previous posts, I should try building the QMessageBox from the ground up, then (somehow) set the button to the center. This is what I have so far.

        QMessageBox *noPresetSelected = new QMessageBox(this);
        noPresetSelected->setWindowTitle("No preset selected");
        noPresetSelected->setFixedSize(450, 200);
        noPresetSelected->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Minimum);
        noPresetSelected->setText("No preset has been selected to edit.");
        noPresetSelected->setIcon(QMessageBox::Warning);

        //Add a QButton
        QPushButton *nMSOk = new QPushButton("Ok", noPresetSelected);
        nMSOk->resize(120, 80);
        nMSOk->setStyleSheet("QPushButton {border: 2px solid #8f8f91;border-radius: 9px;background-color: QLinearGradient(x1: 0, y1: 0, x2: 0, y2: 1,stop: 0 #f6f7fa, stop: 1 #dadbde);font: 25px;outline: none; width: 128px; height: 128px;}"
        "QPushButton:pressed {background-color: QLinearGradient(x1: 0, y1: 0, x2: 0, y2: 1,stop: 0 #dadbde, stop: 1 #f6f7fa) }");
        noPresetSelected->addButton(nMSOk, QMessageBox::AcceptRole);
        /*Somehow, get a function here that would allow for the button to be moved to the center)*/
        noPresetSelected->exec();

I am not sure what potential workarounds I could use in QMessageBox. Thank you for your time and please let me know if more info is required.

[JonB]

@Dummie1138 said in Making a QMessageBox with a single centered button:

Other posts suggest that this is impossible

My reading of that post is that there is an accepted solution from @eyllanesc (who, btw, usually knows what he is talking about)? Assuming that works, how is it "impossible"? I don't understand why you have not tried the approach suggested there?