Return the add_listener method for VTag

[XX]

The add_listener function is needed for my project https://github.com/noogen-projects/yew-mdc-widgets, but it was removed in the #1542 PR: https://github.com/yewstack/yew/pull/1542/files?authenticity_token=Tuuykd78jnZ%2BAdLNBHI59D2wWoJnpGuCUvZPLJvjNMkmLvrDf%2FM0Ap0XHwA0TZAGVPz2sH8w8OU6s1696gisMA%3D%3D&file-filters%5B%5D=.rs#diff-ca7fccc825bdf79bdab83f034636dee4d6727ba13ee5578dc8eb784b1d136478L503

But why? Can I return this method or is it impossible?

[voidpumpkin]

@bakape Do you remember why it got removed?

[bakape]

@voidpumpkin The listener vector was converted into a boxed array to reduce construction overhead. This is a microptimasation that should not break almost all use cases. I also have a PR in the works, that enables allocating said arrays on the stack (among other things), so I don't see this changing. If dynamic size listener arrays are needed, best build vectors, convert them to boxed arrays and then pass that to the VTag.

[voidpumpkin]

@bakape I think your explanation ended up being a little bit too complex for me. By boxed array, I presume, you mean its a slice now (i see the same in the code). And by that it means you have to set all setters at once as its size is not dynamic.

[voidpumpkin]

@XX Could you explain more about what add_listener does and why it is needed? Its hard to grasp what it its and why its needed just from "I use it in X project, please add it back".
I cant imagine personally anyone adding listeners not via DOM api or html! macro, so i would love to understand the core of the issue.

[voidpumpkin]

@bakape Also I see the creator of the issue implemented exactly what you suggested, could you give #2300 a review?

[bakape]

By boxed array, I presume, you mean its a slice now

A boxed array is an owning reference to a heap-allocated static size array. That reference is a Box and implements dereferencing (via std::ops::Deref) to a slice.

I cant imagine personally anyone adding listeners not via DOM api or html! macro, so i would love to understand the core of the issue.

You would need it for writing libraries (or other abstractions), that work on individual VDOM types - lower level API than the html! macro.

Also I see the creator of the issue implemented exactly what you suggested, could you give #2300 a review?

Sure, I'll take a look.