Dynamic creation of selectize choices

[tymsoncyferki]

Hi, is it possible to somehow retrieve what a user is typing in the Selectize field?

What I want to achieve is to get the current text from the input_selectize (like from the input_text), send an API request to weatherapi, receive a response with city names based on this current text, and finally set choices to these cities using update_selectize.

[SamEdwardes]

I wanted to do this as well. I devised a workaround to share when I can create a reprex. It is not perfect, but it does something similar. Here is a preview:

[SamEdwardes]

Below is an example. It would be nice to have a component in the future where you could add new items to the selectize component directly.

requirements.txt

loguru==0.7.2
shiny==0.6.1.1

app.py

from shiny import App, reactive, render, ui
from loguru import logger


def initial_choices() -> list[str]:
    return ["slurm", "kubernetes"]


app_ui = ui.page_fluid(
    ui.input_text(
        "keyword_entry_text_input", 
        placeholder="Enter new regex query...",
        label="(1) Add a new word to selectize."
    ),
    ui.input_action_button(
        'add_new_keyword_button', 
        "(2) Add to Selection",
    ),
    ui.input_selectize( 
        "selected_keywords", 
        choices=initial_choices(),
        selected=None,
        multiple=True,
        label="(3) Select items to include."
    ),
    ui.p("The selected items are..."),
    ui.output_text("selected_items")
)


def server(input, output, session):
    # Initial choice options that could be useful for the person using the
    # dashboard.
    keyword_choices = reactive.Value(initial_choices())
    keyword_selected = reactive.Value([])
   
    @reactive.Effect
    @reactive.event(input.add_new_keyword_button, ignore_init=True)
    def add_new_choice():
        """
        When a user presses the "Add to Selection" button update the
        reactive values.
        """
        logger.debug("'Add to Selection' button has been pressed")
        # Update the reactive values
        new_term = input.keyword_entry_text_input()
        new_choices = list(keyword_choices.get()) + [new_term]
        new_selected = list(keyword_selected.get()) + [new_term]
        logger.debug(f"{new_choices=}")
        logger.debug(f"{new_selected=}")
        keyword_choices.set(new_choices)
        keyword_selected.set(new_selected)

        # Update the input UI:
        ui.update_text("keyword_entry_text_input", value='')
        ui.update_selectize(
            "selected_keywords",
            choices=new_choices,
            selected=new_selected,
            server=False,
        )

    @reactive.Effect
    @reactive.event(input.selected_keywords, ignore_none=True)
    def update_reactive_values_for_selectize():
        """
        When the user makes a change to the selected values in the selectize box
        update the reactive values.
        """
        # Update the reactive values 
        selected_keywords = list(input.selected_keywords())
        logger.debug(f"The selectize input has changed: {selected_keywords}")
        keyword_selected.set(selected_keywords)

    @render.text
    def selected_items():
        return f"{input.selected_keywords()}"


app = App(app_ui, server)