How to handle state management and bind callback functions to child components in Slint.

[ArisuYuki]

I've been working on various web development projects (primarily with Vue), where state management and event binding are the most critical issues. However, in the Slint documentation, I've rarely seen tutorials on how to handle state management and event binding with deeply nested components. For state management, should I set up a global singleton in Slint to manage state across different components?

Additionally, I'm confused about not being able to access any component definitions from Rust code unless they are directly inherited from a Window. If I can't get a handle on these components, how am I supposed to bind callbacks and modify their properties? Most of the examples I've seen only have one or two levels of nesting. In these cases, the examples pass callbacks and change properties through the main App component, but this is clearly unacceptable when the nesting is too deep.

How can I bind a Rust callback or change the property value of a deeply nested child component? Do I have to declare a global singleton for every single nested child component just to modify it and bind events?