express.ui.input_action_button

express.ui.input_action_button(id, label, *, icon=None, width=None, disabled=False, **kwargs)

Creates an action button whose value is initially zero, and increments by one each time it is pressed.

Parameters

id: str

An input id.

label: TagChild

An input label.

icon: TagChild = None

An icon to appear inline with the button/link.

width: Optional[str] = None

The CSS width, e.g. ‘400px’, or ‘100%’

disabled: bool = False

If True, the button will not be clickable. Use update_action_button to dynamically enable/disable the button.

**kwargs: TagAttrValue = {}

Attributes to be applied to the button.

Returns

Type	Description
Tag	A UI element

Notes

Server value

An integer representing the number of clicks.

See Also

• update_action_button
• input_action_link
• event

Examples

#| standalone: true
#| components: [editor, viewer]
#| layout: vertical
#| viewerHeight: 400

## file: app.py
import matplotlib.pyplot as plt
import numpy as np

from shiny import reactive, render
from shiny.express import input, ui

ui.input_slider("n", "Number of observations", min=0, max=1000, value=500)
ui.input_action_button("go", "Go!", class_="btn-success")


@render.plot(alt="A histogram")
# Use reactive.event() to invalidate the plot only when the button is pressed
# (not when the slider is changed)
@reactive.event(input.go, ignore_none=False)
def plot():
    np.random.seed(19680801)
    x = 100 + 15 * np.random.randn(input.n())
    fig, ax = plt.subplots()
    ax.hist(x, bins=30, density=True)
    return fig

#| standalone: true
#| components: [editor, viewer]
#| layout: vertical
#| viewerHeight: 400

## file: app.py
from shiny import reactive
from shiny.express import input, render, ui

ui.input_text("name", "Your Name")
ui.input_action_button("greet", "Say Hello", disabled=True)


@reactive.effect
@reactive.event(input.name)
def set_button_state():
    if input.name():
        ui.update_action_button("greet", disabled=False)
    else:
        ui.update_action_button("greet", disabled=True)


@render.ui
@reactive.event(input.greet)
def hello():
    return ui.p(f"Hello, {input.name()}!", class_="fs-1 text-primary mt-3")