Passing custom properties down to children of a custom component

Anvil Q&A
1

Hi guys,
I looking for a way to pass custom properties from the parent form to a child form. I read the docs (
https://anvil.works/docs/client/custom-components) but it is not clear to my how the initialization works in detail. I was kind of assuming that the custom property is handed downward within the kwargs (**properties) of self.init_components, but this seems not to be the case.

So how can I achieve this?

2

some good examples in the library

Slider would be a good one to start with

3

Thanks @stu, but this explains just custom getters and setters. My case corresponds to the Main Form being a custom component with one custom property which I would like to pass down to the slider component.

4

Like

raise_event_on_children

cascades the event down the children tree, there must be a similar mechanism when the forms initialise.

5

A clone or more pseudo code that you would hope to work might be useful here.

init_components sets the item, initialises any data bindings and sorts out your @properties if you’ve created any.

raise_event_on_children could be useful but it would only go 1 level and would need to use set_event_handler to catch the event.

You could also iterate through components of a form either using form.get_components or by going through its dir with

for component_name in dir(self):
  component = getattr(self, component_name)
  if isinstance(component, Component):
    # do somethings
1 Like
6

Thanks a lot @stucork,
that’s pretty much what I was looking for!