Unexpected behavior with bindable dataclass and input inside a dialog

[benvc]

First Check

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Example Code

from nicegui import binding, ui


@binding.bindable_dataclass
class Data:
    text: str


data = Data(text="some text")


with ui.dialog() as dialog, ui.card():
    ui.input(label="Text").bind_value(data, "text")
    ui.button(
        text="Save",
        on_click=dialog.close,
    )

ui.label().bind_text_from(data, "text")
ui.button(text="Update text", on_click=dialog.open)

Description

The code example is intended to replicate a page where ui elements are bound to a NiceGUI bindable dataclass. I expect the input value inside the dialog to reflect the updated text when the dialog is reopened after a prior save (and dialog close), but the input value displays the original value (pre-update) when the dialog is reopened. If you remove the dialog from this example, the input value retains the updated entry after clicking the save button.

Perhaps, I have overlooked a dialog or input property that needs to be set in order to get the expected behavior. For example, maybe the dialog element resets to its original state on close by default or something like that. However, I searched the documentation and did not find anything that would appear to be related to the behavior observed here. Thanks in advance for any help.

How to reproduce the unexpected behavior:
Start the app.
Click "Update text" to open the dialog.
Change the text in the input.
Click "Save" and the dialog closes.
The print statement in the update_text function displays "data is synced True" and the label element is updated with the changed text.
Click "Update text" to open the dialog.
The input displays the original text rather than the updated text.

NiceGUI Version

2.19.0

Python Version

3.12.10

Browser

Firefox

Operating System

Windows

Additional Context

No response

[falkoschindler]

Hi @benvc,

Unfortunately this is a known bug which we still don't know how to solve: #2149
As a workaround you can set LOOPBACK = True:

input_ = ui.input(label='Text').bind_value(data, 'text')
input_.LOOPBACK = True