Unable to register on_open event for combo box

[WZ-Tong]

Is there an existing issue for this?

• [X] I have searched the existing issues.

Is this issue related to iced?

• [X] My hardware is compatible and my graphics drivers are up-to-date.

What happened?

I can only register on_close event, but not on_open` event. It's useful to refresh items when combo box is selected.

Currently I can use on_option_hovered, but it triggers everytime mouse move over an option

What is the expected behavior?

ComboBox::new().on_open

Version

crates.io release

Operating System

Windows

Do you have any log output?

No response