QMessageBox Buttons Become Unclickable on Android When Applying Stylesheet

[zvoopz]

On Android, applying a stylesheet to any widget (not just QMessageBox) makes QMessageBox buttons unclickable. Even setting an empty stylesheet on any widget causes this issue.

Steps to Reproduce
Create a QMessageBox and display it normally.

QMessageBox::StandardButton reply;
    reply = QMessageBox::question(this, tr("Test"), tr("Clickable?"), QMessageBox::Yes | QMessageBox::No);

The buttons are clickable as expected.

Apply any styleSheet to any widget and the buttons become unclickable on Android. Windows build is fine - no issues.
Even applying an empty rule breaks interactivity

void MainWindow::on_pushButton_clicked()
{
//if next line is uncommented QMessageBox becomes unclickable
    // setStyleSheet("QMessageBox { }"); /this makes QMessageBox unclickable
    QMessageBox::StandardButton reply;
    reply = QMessageBox::question(this, tr("Test "), tr("Clickable?"), QMessageBox::Yes | QMessageBox::No);
    if (reply == QMessageBox::Yes){
        //if uncomment next line next QMessageBox becomes unclickable
        //setStyleSheet("QPushButton { }"); //this makes QMessageBox unclickable as well
         QMessageBox::information(this,"Check it","StyleSheet is set. Is it clickable?" );
          }
}

Tested on Qt Version: [6.8.1] and [6.8.2]
OS: Android 13
Build Android Qt 6.8.2 Clang arm64-v8a

Workarounds Tried
Setting setFocus() and repaint() on QMessageBox - no effect.
Applying the style globally via qApp->setStyleSheet() - no effect.

[jsulm]

@zvoopz How does the style sheet look like?

[zvoopz]

Hi @jsulm !
It is a dark mode for my app. Stylesheet inverts colors. Everething works fine until QMessageBox pops up. Windows build works fine, this problem appears only on Android

Something as follows

void MainWindow::toggleDarkMode()
{

    isDarkMode = !isDarkMode;   

    if(isDarkMode) {
        setStyleSheet("QMainWindow { background-color: #2E2E2E; color: white; }"
                      "QLabel, QPushButton, QCheckBox, QToolButton, QListWidget, QWidget { color: white; }"
                      "QPushButton, QToolButton, QListWidget { background-color: #555; border: 1px solid white; }"
                      "QLineEdit { background-color: #444; color: white; border: 1px solid white; }"
                      "QMessageBox { background-color: #2E2E2E; color: white; }"
                      "QMessageBox QLabel { color: white; }"
                      "QMessageBox QPushButton { background-color: #555; color: white; border: 1px solid white; }"
                      "QComboBox { background-color: #444; color: white; border: 1px solid white; }"
                      "QComboBox QAbstractItemView { background-color: #333; color: white; }");

        //invert images
        //QPixmap pixmap(":/images/my_image.png"); // Load original image
        QImage img = Compass.toImage();
        img.invertPixels(QImage::InvertRgb); // Invert colors
        ui->labelCompass->setPixmap(QPixmap::fromImage(img));
        img = Clock.toImage();
        img.invertPixels(QImage::InvertRgb); // Invert colors
        ui->labelClock->setPixmap(QPixmap::fromImage(img));

        //invert button icons
        invertButtonIcon(ui->windDirectionSelector1of3PushButton);
        invertButtonIcon(ui->windDirectionSelector2of3PushButton);
        invertButtonIcon(ui->windDirectionSelector3of3PushButton);
        invertButtonIcon(ui->singleWindDirectionSelectorPushButton);
        //applyDarkModeToPlot(ui->plotWidget);

    }else{
        setStyleSheet(""); // Reset to default
        ui->labelCompass->setPixmap(QPixmap(":/img/compass.jpg"));
        ui->labelClock->setPixmap(QPixmap(":/img/clock.png"));
        invertButtonIcon(ui->windDirectionSelector1of3PushButton);
        invertButtonIcon(ui->windDirectionSelector2of3PushButton);
        invertButtonIcon(ui->windDirectionSelector3of3PushButton);
        invertButtonIcon(ui->singleWindDirectionSelectorPushButton);
        //applyLightModeToPlot(ui->plotWidget);
    }
}

[zvoopz]

Could you please check if my minimal compilable example provided by the link has a behavior as described?
https://drive.google.com/file/d/1JBucqsDPNZYun_3XvONqfA810eJ2my-c/view?usp=drive_link

[jsulm]

@zvoopz No, I don't have development environment for Android at hand right now.
Maybe will do this evening.

[zvoopz]

So here is my findings. Maybe someone can give me a hint
Applying any styleSheet on Android shifts Z-order of QMessageBox which makes its buttons unclickable

Here what is going on:

//setting styleSheet to any widget breaks interactivity on Android
setStyleSheet("QPushButton { }");
QMessageBox::information(this,"Check the message", "Is it clickable?" );
//it is not clickable on Android

But if we manually set Z-order to the message this message becomes clickable. But further ones ARE NOT

setStyleSheet("QPushButton { }"); //applying styleSheet
        QMessageBox msgBox;
        msgBox.setText("StyleSheet is set. Z-order fixed");
//set stayOnTop flag and it becomes clickable
        msgBox.setWindowFlags(Qt::Dialog | Qt::WindowStaysOnTopHint);
        msgBox.exec();
//Next message is unclickable
QMessageBox::information(this,"Check next message",
                                 "Is it clickable?" ); //No it is not clickable

How to restore correct Z-order for all of my windows and messages after apllying a styleSheet in Android?