Palette
Simple colour palette in linear or grid layouts

This simple custom widget accepts a list of colours when created, and presents these colours as an array of coloured buttons to click. Clicking on a button emits a signal with the clicked colour. Perfect to use in a bitmap drawing application.

Three widgets are provided —

PaletteHorizontal a linear horizontal palette

Horizontal Palette widget Horizontal Palette widget

PaletteGrid a grid palette. This also accepts an optional second parameter n_columns, which is the number of columns to lay the colours out in. The default is 5 (as seen below).

python
PaletteGrid('17undertones', n_columns=5)

GridLayout Palette with 17 undertones GridLayout Palette with 17 undertones

There is also a vertical layout PaletteVertical available.

There are 3 built-in named colour-schemes paired12, category10 and 17undertones.

Paired 12 grid palette Paired 12 grid palette

But you can also provide any list of colours you like when creating the widget.

python
PaletteGrid(['#000003', '#160B39', '#410967', '#6A176E', '#932567', '#BA3655', '#DC5039', '#F2751A', '#FBA40A', '#F6D542', '#FCFEA4'])

Bokeh Inferno 11 Bokeh Inferno 11

Signals

The palette provides only a single signal .selected which is emitted when a colour is selected in the palette. This sends the selected colour, in the same format as it was when setting the palette.

python
palette = PaletteHorizontal(['#000003', '#160B39', '#410967'])
palette.selected.connect(print)

The above would print to the console #000003 or #160B39 or #410967 as each colour was clicked.

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