How to set property requiring more than one parameter?

[paulolieuthier]

I'm trying to set a fixed size for a widget:

gtk! {
    <AspectFrame::new(None, 0.5, 0.5, 1f32, false) size_request=(100, -1)>
        <Button label="xalala" />
    </AspectFrame>
}

I'm passing the parameters as a tuple because that's what feels natural in this case. However, I get an error:

error[E0061]: this function takes 2 parameters but 1 parameter was supplied
  --> example.rs
   |
   |             <AspectFrame::new(None, 0.5, 0.5, 1f32, false) size_request=(100, -1)>
   |                                                            ^^^^^^^^^^^^ expected 2 parameters

How can I set it? Is it necessary to add helper to vgtk (WidgetHelpers) for it?

[paulolieuthier]

Just for the record, setting the size can be done using distinct properties for width and height:

gtk! {
    <AspectFrame::new(None, 0.5, 0.5, 1f32, false)
                property_width_request=100
                property_height_request=100>
        <Button label="xalala" />
    </AspectFrame>
}

[bodil]

The right thing to do here, I think, is to go with the two individual properties. However, I hate those "property_" names and I think I'll need to add helper methods for them. Leaving the issue open for that.

[archseer]

Some properties don't have a single setter though: see set_default_size (It's mentioned in the docs to be preferred over set_size_request https://valadoc.org/gtk+-3.0/Gtk.Widget.set_size_request.html) I think we should accept (1, 2) as multiple parameters (or use a different type of brackets maybe)

…

On Wed, 27 Nov 2019 at 22:28, Bodil Stokke ***@***.***> wrote: The right thing to do here, I think, is to go with the two individual properties. However, I hate those "property_" names and I think I'll need to add helper methods for them. Leaving the issue open for that. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#21?email_source=notifications&email_token=AAKPF5UJBMPGKKG2KTARIALQVZYW7A5CNFSM4JQZ52QKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEFJP4GQ#issuecomment-559087130>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAKPF5X2HDDQESS2API2TUDQVZYW7ANCNFSM4JQZ52QA> .

[bodil]

But those two set different properties - Window::set_default_size sets Window::default-width and Window::default-height while Widget::set_size_request sets Widget::height-request and Widget::width-request. And there are individual setters for all of them, albeit with the annoying property_ prefix.

The reason I'm extremely reluctant to add syntax for this is that the only reasonable syntax I can imagine for it ((1, 2)) would override the syntax for setting a property that takes a tuple, which would be a plausible scenario when custom Gtk classes land in gtk-rs, especially if it turns out those make a better way to build subcomponents. I'm also just generally wary of adding more syntax than strictly necessary.

[archseer]

Weird, I'm not sure how I missed that, thanks!

Agreed, although I'd still like a way to be able to wrap calls that require more than one argument. I'm currently experimenting with adding an extension trait for https://github.com/subgraph/gtk-layer-shell-rs/blob/master/examples/example.rs#L21-L39

I guess my trait's method could just take a single parameter that would be a tuple, i.e. (gtk_layer_shell::Edge::Left, 40) and then I would unwrap that and call the actual setter.

[nt8r]

This is also necessary for setters like Notebook::set_action_widget.

On the topic of syntax, what about adopting tuple-splatting from python (e.g., size_request=*(100, -1))?