Accordion

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In [1]:
import panel as pn
pn.extension()

Accordion layouts are a type of Card layout that allows switching between multiple objects by clicking on the corresponding card header. The labels for each card may be defined explicitly as part of a tuple, and otherwise default to the name parameter of the card's contents. Like Column and Row, Tabs has a list-like API that allows interactively updating and modifying the cards using methods append, extend, clear, insert, pop, remove and __setitem__ (to replace the contents).

Parameters:

  • active (list, default=[]): The indexes of the currently displayed cards. Updates when a card is expanded or collapsed and may also be set to programmatically control which cards are shown.
  • objects (list): The list of objects to display in the Column. Should not generally be modified directly except when replaced in its entirety.
  • toggle (bool): Whether to toggle between the available cards, activating only one at a time (if True), or (if False) whether to allow multiple cards to be expanded simultaneously.

Styling-related parameters:

  • active_header_background (str): The background color of the header when the Card is expanded.
  • header_color (str): The color of the header text.
  • header_background (str): The background color of the header.

For further layout and styling-related parameters see the customization user guide.


Accordion

An Accordion layout can either be instantiated as empty and populated after the fact, or by using a list of objects provided on instantiation as positional arguments. If the objects are not already Panel components they will each be converted to one using the pn.panel conversion method. Unlike other panel types, Accordion also accepts tuples to specify the title of each tab; if no name is supplied explicitly the name of the underlying object will be used.

In [2]:
from bokeh.plotting import figure

p1 = figure(width=300, height=300, name='Scatter', margin=5)
p1.scatter([0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 2, 1, 0])

p2 = figure(width=300, height=300, name='Line', margin=5)
p2.line([0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 2, 1, 0])

accordion = pn.Accordion(('Scatter', p1), p2)
accordion
Out[2]:

The contents of the Accordion.objects list should never be modified individually, because Panel cannot detect when items in that list have changed internally, and will thus fail to update any already-rendered views of those objects (and their card titles!). Instead, use the provided methods for adding and removing items from the list. The only change that is safe to make directly to Accordion.objects is to replace the list of objects entirely. As a simple example of using the methods, we might add an additional widget to the Accordion using the append method:

In [3]:
p3 = figure(width=300, height=300, name='Square', margin=5)
p3.square([0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 2, 1, 0], size=10)

accordion.append(p3)

On a live server or in a notebook the accordion displayed above will dynamically expand to include the new card. To see the effect in a statically rendered page, we will display the accordion a second time:

In [4]:
accordion
Out[4]:

active

In addition to being able to modify the objects using methods we can also get and set the currently active cards as a list of integers, which will update any rendered views of the object:

In [5]:
print(accordion.active)
accordion.active = [0, 2]
[]

toggle

When toggle is enabled only one card can be active at the same time, i.e., expanding one card will collapse the other active cards (much like a Tabs layout).

In [6]:
accordion.clone(toggle=True, active=[0])
Out[6]:

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