A way to view all active bindings?

[flintcreek]

Question

Is there a way to inspect the list of all active bindings in a nicegui app? I'm getting the "binding propagation" message, and it would be helpful to see all the active bindings so I can begin optimizing.

[thetableman]

You can access active bindings using binding.active_links, here's a basic example:

from nicegui import ui, binding

bind = {1: 'a', 2: 'b', 3: 'c'}
options = [1, 2, 3]

ui.select(options=options, value=1).bind_value(bind, 1).classes('w-24')
ui.radio(options=options, value=2).bind_value(bind, 2).props('inline')
ui.slider(value=3, min=1, max=3).bind_value(bind, 3).classes('w-24')

for b in binding.active_links:
    print(b)

ui.run()

[flintcreek]

Simon- Thank you, I guess I could have dug deeper before asking since that now seems so obvious. I do wonder if bindings to and from storage are polled in the active links loop? They show up in the list. Is there a way to make those BindableProperty objects?

…

-Matt On Jan 15, 2025, at 9:34 PM, Simon Robinson ***@***.***> wrote:  You can access active bindings using binding.active_links, here's a basic example: from nicegui import ui, binding bind = {1: 'a', 2: 'b', 3: 'c'} options = [1, 2, 3] ui.select(options=options, value=1).bind_value(bind, 1).classes('w-24') ui.radio(options=options, value=2).bind_value(bind, 2).props('inline') ui.slider(value=3, min=1, max=3).bind_value(bind, 3).classes('w-24') for b in binding.active_links: print(b) ui.run() — Reply to this email directly, view it on GitHub<#4230 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ARO5CWOWVPFNBRQMQAPHJUL2K4SDHAVCNFSM6AAAAABVICCNPCVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTCOBVGAYTGOA>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[thetableman]

I'm not sure about that - app.storage properties usually have to be made of serializable data so I wouldn't expect a binding object to work in that scenario.

[falkoschindler]

Hm, I'm not sure either. BindableProperties are based on descriptors to immediately notice write access. And app.storage, on the other hand, is based on observable dictionaries, which doesn't seem very compatible.

But I see a vague chance that binding methods could handle observable collections by registering another change handler for binding propagation. This could be another if-condition here:

nicegui/nicegui/binding.py

Lines 92 to 95 in ca5e9bd

	bindings[(id(self_obj), self_name)].append((self_obj, other_obj, other_name, forward))
	if (id(self_obj), self_name) not in bindable_properties:
	active_links.append((self_obj, self_name, other_obj, other_name, forward))
	_propagate(self_obj, self_name)

I'm just not sure if this creates possible memory leaks etc. because these new change handlers need to be cleaned up properly when removing UI elements.

In principle it seems to work, even when changing nested entries:

A = observables.ObservableDict({'a': 1, 'b': {'c': 3, 'd': 4}})
label = ui.label(str(A['b']))
A['b'].on_change(lambda: label.set_text(str(A['b'])))
ui.button('Update', on_click=lambda: A['b'].update(d=A['b']['d'] + 1))