I want to invoke a function when user assigns or accesses its value to ui.input or ui.number programmatically but i am not able to write @property & @value.setter

[rajeshhalyal]

First Check

• I have tried what I know and can program till now
• I added a very descriptive title here.
• I have checked the FAQs for a similar question and didn't find it.
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Example Code

class numberinput(ui.number):
    user_on_blur = None
    user_on_blur_arguments = None
    old_value = None
    user_on_focus = None
    user_on_change = None
    user_value_change_event_on_exit = None
    user_on_value_set = None
    user_on_value_get = None



    async def custom_onchange(self, e):
        if self.user_on_change:
            if inspect.iscoroutinefunction(self.user_on_change):
                funcresult = await self.user_on_change(self)
            else:
                funcresult = self.user_on_change(self)

    async def onfocus(self):
        self.old_value = self.value
        funcresult = True
        if self.user_on_focus:
            if inspect.iscoroutinefunction(self.user_on_focus):
                funcresult = await self.user_on_focus(self)
            else:
                funcresult = self.user_on_focus(self)
        return funcresult

    async def onblur(self):
        funcresult = True
        if (self.value != self.old_value) and (self.user_value_change_event_on_exit):
            if inspect.iscoroutinefunction(self.user_value_change_event_on_exit):
                funcresult = await self.user_value_change_event_on_exit(self)
            else:
                funcresult = self.user_value_change_event_on_exit(self)
        if funcresult == False:
            self.value = self.old_value
            self.run_method('focus')
            return funcresult

        if self.user_on_blur:
            if inspect.iscoroutinefunction(self.user_on_blur):
                funcresult = await self.user_on_blur(self, self.user_on_blur_arguments)
            else:
                funcresult = self.user_on_blur(self, self.user_on_blur_arguments)

        if funcresult == False:
            self.value = self.old_value
            self.run_method('focus')

        return funcresult

    def __init__(self, *args, on_change=None, **kwargs):
        # region additional parameters passed to ui.input
        if 'on_focus' in kwargs:
            self.user_on_focus = kwargs['on_focus']
            kwargs.pop('on_focus')

        if 'on_blur' in kwargs:
            self.user_on_blur = kwargs['on_blur']
            kwargs.pop('on_blur')

        if 'value_change_exit' in kwargs:
            self.user_value_change_event_on_exit = kwargs['value_change_exit']
            kwargs.pop('value_change_exit')

        if 'on_blur_arguments' in kwargs:
            self.user_on_blur_arguments = kwargs['on_blur_arguments']
            kwargs.pop('on_blur_arguments')

        # endregion additional parameters passed to ui.input

        self.user_on_change = on_change
        super().__init__(*args, on_change=self.custom_onchange, **kwargs)

        self.on('focus', lambda: self.onfocus())
        self.on('blur', lambda: self.onblur())
        self.props('input-class="text-right"')

    @property
    def value(self):
       return self.value

    @value.setter
    def value(self, a):
        self._value = a
        self._props['value'] = a  # Update NiceGUI's internal value
        self.update()  # Trigger UI update
        if self.user_on_value_set:
            funcresult = self.user_on_value_set(self)

Description

I want to invoke a function when user assigns or accesses its value to ui.input or ui.number programmatically but i am not able to write @Property & @value.setter
if i write this i get a endless loop what other options do i have to achieve the same effect

NiceGUI Version

2.23.3

Python Version

3.12

Browser

Chrome

Operating System

Windows

Additional Context

i have a chain of ui.input which when assigned a value programmatically change values of other ui.number and ui.input depending on the value assigned

[Anindya088]

Hi @rajeshhalyal ,

Do you mean to just change or access the values of the elements?
Then we can do .value or .set_value

For ex: this will change the value of the input on button click

input = ui.input(value='Initial value')
ui.button('Change input value', on_click=lambda: input.set_value('New value'))