How to validate input of entry

[DBLouis]

How would you implement input validation on an entry widget? I found an this example in C and try to do the same in Rust. I am struggling with signal_handler_block and signal_handler_unblock because I don't know how to get the SignalHandlerId.

[sdroege]

The connect_blablabla() functions return the SignalHandlerId that you can use for this.

[DBLouis]

Ok but this kind of a vicious circle because I need the SignalHandlerId in the closure that I connect.

[sdroege]

Those things are annoying. You could store it in a Rc<RefCell<Option<SignalHandlerId>>> outside the closure (or in some other way in your application state), and pass a reference to that into the signal handler closure to get access to it.

[DBLouis]

I guess there is no other way. Is g_signal_handlers_block_by_func could be made available eventually?

[sdroege]

No as you don't have access to the function parameter you'd pass there. It's a private function specific to the closure you pass in, your closure (but boxed) becomes the user data.

[DBLouis]

Ok thank you