Allow TreeNodes to have CSS classes

[KalleDK]

I'm writing a program that uses the tree to navigate, and I would love to be able to have classes on the nodes in such a way that I can mark all "warning" nodes with a color or all "ok" nodes woth another. Right now I prepend an emoji, but it gets cluttery very fast.

I have a workaround right now with Text.assemble("label", style="red")... But this does not work well with the css afaik (also it would be lovely to use the theme colors instead of hardcoding)

[KalleDK]

Or as minimal viable allow me to apply a color like $warning for the label

[darrenburns]

You can access the theme variables in the App.theme_variables attribute. This is a dict which maps the variable name to the value it holds.

So from a widget, self.app.theme_variables.get("text-warning") will retrieve the $text-warning variable (which is legible when applied as a text colour across all themes, so you probably want that instead of $warning).

[KalleDK]

And that can be applied via the Text.assemble? And it updates when the user changes theme?

[darrenburns]

Yes, it just returns a string, so it'll work anywhere strings like "red" and "#ff0000" work, including in Text.assemble.

The value will update when the user changes theme, yeah.

[KalleDK]

I see - but the nodes needs to be "updated" when the user changes theme via the control palette. But it is still way better then what I have :)