`ui.number`: change event argument differs from `value` property about nicegui HOT 3 CLOSED

It seems like this is designed to be 0.
In elements/number.py, overwrited function _value_to_event_value function convert value to zero when value is None.
Should it keep None?

    def _value_to_event_value(self, value: Any) -> Any:
        return float(value) if value else 0

from nicegui.

Hmm, this is interesting.
I was playing around with this and noticed some interesting things.
Firstly, as is mentioned above, the fix for this issue would be what @Lucas-lyh described. Switch the 0 to a None and it works. I'll submit a PR for this once I get home (unless either of you want to do it @falkoschindler )
However, the reason I said this was interesting, is because I tried putting in letters into the number element. I realize that the reason you can input 'e' is because of numbers like 1e6, as this is a common representation of them. However, the reason I am intrigued is because you can put the 'e' there without a prefix. Is this the expected behaviour? Are we supposed to be able to put e7, or should we require it to have a prefix?

from nicegui.

@Lucas-lyh I guess you're right. The event value should also be None when clearing the number input.

Here is some code I experimented with to compare model and event values of ui.input and ui.number:

i = ui.input(placeholder='Type here').props('clearable').on_value_change(lambda e: print(f'You typed: "{e.value}"'))
ui.label().bind_text_from(i, 'value', lambda v: f'You typed: "{v}"')

n = ui.number(placeholder='Type here').props('clearable').on_value_change(lambda e: print(f'You typed: "{e.value}"'))
ui.label().bind_text_from(n, 'value', lambda v: f'You typed: "{v}"')

@frankvp11 Yes, a PR would be great!

Regarding the "e": This seems to be browser-specific behavior of the HTML input element:

ui.html('<input type="number">')

In Chrome you are allowed to type a single "e", while Safari allows to type multiple "e"s. So it's probably out of our control.

from nicegui.