DiscretePlayer.ipynb

Kernel: Unknown Kernel

import panel as pn

pn.extension()

The DiscretePlayer widget displays media-player-like controls that allow playing and stepping through the provided options. When playing it triggers events at a pre-defined interval on the frontend, advancing the player value each time. It falls into the broad category of single-value, option-selection widgets that provide a compatible API and include the AutocompleteInput, Select and DiscreteSlider widgets.

Discover more on using widgets to add interactivity to your applications in the how-to guides on interactivity. Alternatively, learn how to set up callbacks and (JS-)links between parameters or how to use them as part of declarative UIs with Param.

Parameters:

For details on other options for customizing the component see the layout and styling how-to guides.

Core

• direction (int): Current play direction of the Player (-1: playing in reverse, 0: paused, 1: playing).

• interval (int): Interval in milliseconds between updates

• loop_policy (str): Looping policy; must be one of 'once', 'loop', or 'reflect'

• options (list or dict): A list or dictionary of options to select from

• value (object): The current value; must be one of the option values

• value_throttled (object): The current value throttled until mouseup (when selected using slider)

Display

• disabled (boolean): Whether the widget is editable

• name (str): The title of the widget

• scale_buttons (float): The scaling factor to resize the buttons

• show_loop_controls (boolean): Whether radio buttons allowing to switch between loop policies options are shown

• show_value (boolean): Whether to display the value of the player

• value_align (str): Where to display the value; must be one of 'start', 'center', 'end'

• visible_buttons (list[str]): The buttons to display on the player ('slower', 'first', 'previous', 'reverse', 'pause', 'play', 'next', 'last', 'faster')

• visible_loop_options (list[str]): The loop options to display on the player. ('once', 'loop', 'reflect')

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The widget has a number of buttons to go to the first or last value, step forward or backward, and play and pause the widget. It also provides control over the loop_policy, which determines whether to play 'once', 'loop', or 'reflect'. Additionally - and + buttons slow down and speed up the player speed.

discrete_player = pn.widgets.DiscretePlayer(name='Discrete Player', options=[2, 4, 8, 16, 32, 64, 128],
                                            value=8, loop_policy='loop', show_value=True, value_align='start')

discrete_player

Like most other widgets, DiscretePlayer has a value parameter that can be accessed or set:

discrete_player.value

The DiscretePlayer can be controlled programmatically using the direction parameter which has three possible states:

• -1: playing in reverse

• 0: paused

• 1: playing

Alternatively it can be controlled via the .play, .pause and .reverse methods:

import time

discrete_player.play()
time.sleep(2)
discrete_player.reverse()
time.sleep(2)
discrete_player.pause()

The DiscretePlayer can be slimmed down by setting scale_buttons, show_loop_controls, visible_buttons, and/or visible_loop_options.

discrete_player = pn.widgets.DiscretePlayer(name='Player', visible_buttons=["play", "pause"], scale_buttons=0.9, show_loop_controls=False, width=150)
discrete_player

Controls

The DiscretePlayer widget exposes a number of options which can be changed from both Python and Javascript. Try out the effect of these parameters interactively:

pn.Row(discrete_player.controls(jslink=True), discrete_player)