widgets: spinner (dropdown selection), integer/float input, imgui style tree

[aentity]

Wondering about support for following widgets:

1. Spinner, dropdown selection with N set of known values
2. Typed integer/float input fields, for easy numeric inputs
3. Imgui style "tree", which is collapsible (nice for preserving space), and allows for nesting of more trees

Do you plan to support 1/2, with 3 maybe a wishlist item?

[hecrj]

Yes, I think we should support these widgets or a variation of them in the long run:

1. A combobox or similar is the main widget I think we should build when implementing Layers #30.
2. A number field should be possible currently. The main challenge here is to reuse text editing logic nicely. Text Selection for text_input widget #202 is somewhat related to this.
3. A tree widget would be great, but I am not sure if we will currently find any important blockers. I'd love to see exploration attempts in this area.

[loewenheim]

I'd love to take a stab at the tree widget, but I think I'm gonna need some pointers. The way I see it, a tree contains some sort of content and a vector of children. But when rendering it, there also has to be something you can click to collapse it. Should that just be a Button? And if so, at what point is it created? Is it part of the Tree struct?

[Kaffiend]

I would also like to add input masks and relevant validation and placeholders to depict the mask, ie. phone, zip+4, email, date. As for date is concerned a simple mask would suffice but maybe a more explicit control with calendar popup would be a consideration as well. similar to a dropdown.
edit: reference