"some Js Files Act More Like Libraries - They [...] Never Manipulate Qml Component Instances Directly" - Middle Ground?

Quote from Defining JavaScript Resources In QML: Some JavaScript files act more like libraries - they provide a set of helper functions that take input and compute output, but nev

Solution 1:

I think that the line you quoted from the documentation is incorrect, or at least very poorly worded; you can still have a JS file with .pragma library in it and manipulate QML objects that are passed in as arguments to its functions. The sentence was probably referring to the previous section.

Solution 2:

To share data across qml files, consider using a qml Singleton.

For data sharing purpose, I would not suggest using .pragma library (@Mitch) for following reasons.

1. .pragma library js provides limited functionality in qml object manipulation. While simple qml object manipulation (like property reading/writing) could be done with a .pragma library js, it does NOT allow creating/deleting qml objects (as you can in regular non-library js). It will suck when your application becomes dynamic.

2. .pragma library creating only one instance is merely an optimization in Qt implementation. It's never guaranteed that Qt creates exactly one instance, nor that your data would actually be shared.

3. Well, .pragma library is not designed to do data sharing work from the very beginning. Just, don't try to do it this way.