[Python] How do I send a callback every time the clipboard changes?

[isoraqathedh]

From my last question, I am currently porting a program that originally uses Tk to instead use Slint.

A problem I have encountered is that I can't send a custom event in Slint. Tk can accept and fire custom events (conceptually they are strings with something attached to them which I don't use) so you can call, e.g. Tk.root.bind to have a function be called and then run on some other thread.

In Slint, trying to call a method from the app object panics, as it cannot be sent across threads. The best I can think of is to make a component like:

Clipwait {
  callback new-clipboard();
}

but I have no idea how to implement such a thing. Previously I have just waited on an external process called clipnotify.

[tronical]

Hmm, I admit I don't now what APIs to use for watching for the clipboard, and indeed we don't have that for Slint itself. But I might be able to help with this:

In Slint, trying to call a method from the app object panics, as it cannot be sent across threads.

In the upcoming release, we're adding support for asyncio: https://snapshots.slint.dev/master/docs/python/slint.html#asynchronous-io

This will include call_soon_threadsafe(), so you could write asyncio.get_event_loop().call_soon_threadsafe(...).

You could try this out with our Nightly: https://github.com/slint-ui/slint/releases/tag/nightly