How do I support app variants in a Qt application

I've been struggling a bit on how to properly support app variant in a Qt project. The project uses QML and QMake. Maybe my search skills are lacking but I have not been able to find any specifics on what best practices are on how to support app variants in a Qt project. The app will stay consistent across variants except for using specific variant images and colors etc. so the QML code should be generic.

What I currently have considered is adding a CONFIG argument when building the project that will include an app specific .qrc file specifying specific resources for the variant. This works somewhat in the sense that if I have the following

<RCC>
    <qresource prefix="/">
        <file alias="icon">icons/icon.png</file>
    </qresource>
</RCC>


<RCC>
    <qresource prefix="/">
        <file alias="icon">variant/icons/icon.png</file>
    </qresource>
</RCC>

Note the alias was to have a common name for both pngs so it can be referenced like this.

"qrc:/icon"

However, it will always pick the one in the base .qrc file and only the one in the variant file if missing from the base .qrc. It does not seem to matter if the variant .qrc is included last.

Anyway, any pointers to how (and if) Qt have proper support for building app variants will be much appreciated. For instance is creating a project for each variant a better approach?

QFileSelector allows you to use different versions of files based on things like language, OS, or whatever other selector you want to use. You place your variants in separate directories prefixed with '+', like this:

    images/background.png
    images/+android/background.png

In this example, if your OS is detected as android, it will select the +android/background.png, but any other OS will use the default background.png.

If using QML, there is QQmlFileSelector. Use it like this:

QQmlEngine engine;
QQmlFileSelector* selector = new QQmlFileSelector(&engine);

Since selectors require you to replace entire files, there is the downside of potentially having a lot of duplicated code. So ideally you should reduce the variant code to as small a component as possible. For example, rather than duplicating an entire dialog, if you can pull out the header as a component and just duplicate that piece, you'll save a lot of time and headaches.