dcc.Textarea Documentation

dcc.Textarea is a wrapper around the <textarea> HTML component.

It is like a dcc.Input except that allows for multiple lines of text.

Simple dcc.Textarea Example

import dash
from dash.dependencies import Input, Output
import dash_html_components as html
import dash_core_components as dcc

app = dash.Dash(__name__)

app.layout = html.Div([
    dcc.Textarea(
        id='textarea-example',
        value='Textarea content initialized\nwith multiple lines of text',
        style={'width': '100%', 'height': 300},
    ),
    html.Div(id='textarea-example-output', style={'whiteSpace': 'pre-line'})
])

@app.callback(
    Output('textarea-example-output', 'children'),
    [Input('textarea-example', 'value')]
)
def update_output(value):
    return 'You have entered: \n{}'.format(value)

if __name__ == '__main__':
    app.run_server(debug=True)

Update dcc.Textarea callback on button press

import dash
from dash.dependencies import Input, Output, State
import dash_html_components as html
import dash_core_components as dcc

app = dash.Dash(__name__)

app.layout = html.Div([
    dcc.Textarea(
        id='textarea-state-example',
        value='Textarea content initialized\nwith multiple lines of text',
        style={'width': '100%', 'height': 200},
    ),
    html.Button('Submit', id='textarea-state-example-button', n_clicks=0),
    html.Div(id='textarea-state-example-output', style={'whiteSpace': 'pre-line'})
])

@app.callback(
    Output('textarea-state-example-output', 'children'),
    [Input('textarea-state-example-button', 'n_clicks')],
    [State('textarea-state-example', 'value')]
)
def update_output(n_clicks, value):
    if n_clicks > 0:
        return 'You have entered: \n{}'.format(value)

if __name__ == '__main__':
    app.run_server(debug=True)

dcc.Textarea Properties

Access this documentation in your Python terminal with:
```python

help(dash_core_components.Textarea)
```

id (string; optional): The ID of this component, used to identify dash components in callbacks. The ID needs to be unique across all of the components in an app.

autoFocus (string; optional): The element should be automatically focused after the page loaded.

accessKey (string; optional): Defines a keyboard shortcut to activate or add focus to the element.

cols (string | number; optional): Defines the number of columns in a textarea.

className (string; optional): Often used with CSS to style elements with common properties.

contentEditable (string | boolean; optional): Indicates whether the element’s content is editable.

contextMenu (string; optional): Defines the ID of a <menu> element which will serve as the element’s context menu.

disabled (string | boolean; optional): Indicates whether the user can interact with the element.

dir (string; optional): Defines the text direction. Allowed values are ltr (Left-To-Right) or rtl (Right-To-Left)

draggable (a value equal to: ‘true’, ‘false’ | boolean; optional): Defines whether the element can be dragged.

form (string; optional): Indicates the form that is the owner of the element.

hidden (string; optional): Prevents rendering of given element, while keeping child elements, e.g. script elements, active.

lang (string; optional): Defines the language used in the element.

loading_state (dict; optional): Object that holds the loading state object coming from dash-renderer. loading_state has the following type: dict containing keys ‘is_loading’, ‘prop_name’, ‘component_name’. Those keys have the following types:

  • is_loading (boolean; optional): Determines if the component is loading or not
  • prop_name (string; optional): Holds which property is loading
  • component_name (string; optional): Holds the name of the component that is loading

maxLength (string | number; optional): Defines the maximum number of characters allowed in the element.

minLength (string | number; optional): Defines the minimum number of characters allowed in the element.

name (string; optional): Name of the element. For example used by the server to identify the fields in form submits.

n_blur (number; default 0): Number of times the textarea lost focus.

n_blur_timestamp (number; default -1): Last time the textarea lost focus.

n_clicks (number; default 0): Number of times the textarea has been clicked.

n_clicks_timestamp (number; default -1): Last time the textarea was clicked.

placeholder (string; optional): Provides a hint to the user of what can be entered in the field.

persistence (boolean | string | number; optional): Used to allow user interactions in this component to be persisted when the component - or the page - is refreshed. If persisted is truthy and hasn’t changed from its previous value, a value that the user has changed while using the app will keep that change, as long as the new value also matches what was given originally. Used in conjunction with persistence_type.

persisted_props (list of a value equal to: ‘value’s; default ['value']): Properties whose user interactions will persist after refreshing the component or the page. Since only value is allowed this prop can normally be ignored.

persistence_type (a value equal to: ‘local’, ‘session’, ‘memory’; default 'local'): Where persisted user changes will be stored: memory: only kept in memory, reset on page refresh. local: window.localStorage, data is kept after the browser quit. session: window.sessionStorage, data is cleared once the browser quit.

readOnly (boolean | a value equal to: ‘readOnly’, ‘readonly’, ‘READONLY’; optional): Indicates whether the element can be edited. readOnly is an HTML boolean attribute - it is enabled by a boolean or ‘readOnly’. Alternative capitalizations readonly & READONLY are also acccepted.

required (a value equal to: ‘required’, ‘REQUIRED’ | boolean; optional): Indicates whether this element is required to fill out or not. required is an HTML boolean attribute - it is enabled by a boolean or ‘required’. Alternative capitalizations REQUIRED are also acccepted.

rows (string | number; optional): Defines the number of rows in a text area.

spellCheck (a value equal to: ‘true’, ‘false’ | boolean; optional): Indicates whether spell checking is allowed for the element.

style (dict; optional): Defines CSS styles which will override styles previously set.

tabIndex (string | number; optional): Overrides the browser’s default tab order and follows the one specified instead.

title (string; optional): Text to be displayed in a tooltip when hovering over the element.

value (string; optional): The value of the textarea

wrap (string; optional): Indicates whether the text should be wrapped.