Initialize `background-image` with an image from resource in gtkmm

[Master811129]

Hello, assume I created a gtk app with a label which i sytled it using background-color using the Gtk::CssProvider like this:

pseudo-code

MainWindow::MainWindow():
MyLabel("Hello")
{
    provider = Gtk::CssProvider::create();
    provider->load_from_data(
    "#BackgroundImage{"
    "background-image:url(\"file:///home/user/Desktop/sonbg.jpg\");"
    "background-size:100% 100%;"
    "opacity:0.3;"
    "}"
    );
    MyLabel.set_name("BackgroundImage");
    MyLabel.get_style_context()->add_provider(provider, 1);
}

everything is perfect but i dont know how to set the background-image in my css string to get the image from reource. Please Help me. Thank you.

[Master811129]

add the resources properly to the project and interact with them using resource prefix like this:
background-image:url("resource:///org/custom/example/sonbg.jpg");
Thank you Andrew.