Qt stylesheet for all QProgressBars programmatically (C++)

Question

Having trouble understanding how to programmatically set a stylesheet to be applied on several (or even all) widgets in Qt Creator 4.1 (Qt 5.7) with C++.

For example, say I have 3 progress bar widgets; I have explicitly set each with the same stylesheet with css like so:

ui->c1->setStyleSheet("QProgressBar {"
                          "background-color: #74c8ff;"
                          "color: #0a9dff;"
                          "border-style: outset;"
                          "border-width: 2px;"
                          "border-color: #74c8ff;"
                          "border-radius: 7px;"
                          "text-align: left; }"

                          "QProgressBar::chunk {"
                          "background-color: #010327; }");

ui->c2->setStyleSheet("QProgressBar {"
                          "background-color: #74c8ff;"
                          "color: #0a9dff;"
                          "border-style: outset;"
                          "border-width: 2px;"
                          "border-color: #74c8ff;"
                          "border-radius: 7px;"
                          "text-align: left; }"

                          "QProgressBar::chunk {"
                          "background-color: #010327; }");

ui->c3->setStyleSheet("QProgressBar {"
                          "background-color: #74c8ff;"
                          "color: #0a9dff;"
                          "border-style: outset;"
                          "border-width: 2px;"
                          "border-color: #74c8ff;"
                          "border-radius: 7px;"
                          "text-align: left; }"

                          "QProgressBar::chunk {"
                          "background-color: #010327; }");

I would like to use the Qt Stylesheets to create a stylesheet for my widgets and avoid all this code suplication.

After reading the docs, the syntax would be like this :

QProgressBar
{
    background: #74c8ff;
    color: #0a9dff;
    border-style: outset;
    border-width: 2px;
    border-color: #74c8ff;
    border-radius: 7px;
    text-align: left;
}
QProgressBar::chunk
{
    background-color: #010327;
}

but, apparently you cannot copy the parameter names as used in a setStylesheet with css directly to a syntax like the one above.

I also tried something like this

QProgressBar.setStyleSheet("QProgressBar {"
                           "background-color: #74c8ff;"
                           "color: #0a9dff;"
                           "border-style: outset;"
                           "border-width: 2px;"
                           "border-color: #74c8ff;"
                           "border-radius: 7px;"
                           "text-align: left; }"

                           "QProgressBar::chunk {"
                           "background-color: #010327; }");

None of the above worked (undeclared identifiers and syntax errors).

Could someone provide an example of how you can achieve defining a single stylesheet with the above parameters to be applied for all widgets? If you could point to a resource (I could not find anything!) that explains the available parameters to achive my goal, that would be as good).

Finally, if such a stylesheet is created for all progress bars, how can I exclude one progress bar (or any widget for that matter) from having that stylesheet and have instead a different one?

Answer 1

Use qApp->setStyleSheet instead of QProgressBar.setStyleSheet to set stylesheet for all widgets in your application. More examples here: http://doc.qt.io/qt-5/stylesheet-examples.html