QColormapComboBox

QComboBox variant to select from a specific set of colormaps.

requires cmap

This widget uses the cmap library to provide colormaps. You can install it with:

# use the `cmap` extra to include colormap support
pip install superqt[cmap]

ColorMapLike objects

Colormaps may be specified in a variety of ways, such as by name (string), an iterable of a color/color-like objects, or as a cmap.Colormap instance. See cmap documentation for details on all ColormapLike types

Example

from cmap import Colormap
from qtpy.QtWidgets import QApplication

from superqt import QColormapComboBox

app = QApplication([])

cmap_combo = QColormapComboBox()
# see note above about colormap-like objects
# as names from the cmap catalog
cmap_combo.addColormaps(["viridis", "plasma", "magma", "gray"])
# as a sequence of colors, linearly interpolated
cmap_combo.addColormap(("#0f0", "slateblue", "#F3A003A0"))
# as a `cmap.Colormap` instance with custom name:
cmap_combo.addColormap(Colormap(("green", "white", "orange"), name="MyMap"))

cmap_combo.show()
app.exec()

Style Customization

Note that both the LineEdit and the dropdown can be styled to have the colormap on the left, or fill the entire width of the widget.

To make the CombBox label colormap fill the entire width of the widget:

from superqt.cmap import QColormapLineEdit
cmap_combo.setLineEdit(QColormapLineEdit())

To make the CombBox dropdown colormaps fill less than the entire width of the widget:

from superqt.cmap import QColormapItemDelegate
delegate = QColormapItemDelegate(fractional_colormap_width=0.33)
cmap_combo.setItemDelegate(delegate)

Qt Class

QComboBox

Signals

currentColormapChanged

Methods

A drop down menu for selecting colors.

Parameters:

Name	Type	Description	Default
parent	QWidget	The parent widget.	None
allow_user_colormaps	bool	Whether the user can add custom colormaps by clicking the "Add Colormap..." item. Default is False. Can also be set with setUserAdditionsAllowed.	False
add_colormap_text	str	The text to display for the "Add Colormap..." item. Default is "Add Colormap...".	'Add Colormap...'

addColormap(cmap: ColorStopsLike) -> None

Adds the colormap to the QComboBox.

addColormaps(colors: Sequence[Any]) -> None

Adds colors to the QComboBox.

currentColormap() -> Colormap | None

Returns the currently selected Colormap or None if not yet selected.

itemColormap(index: int) -> Colormap | None

Returns the color of the item at the given index.

setCurrentColormap(color: Any) -> None

Adds the color to the QComboBox and selects it.

setUserAdditionsAllowed(allow: bool) -> None

Sets whether the user can add custom colors.

If enabled, an "Add Colormap..." item will be added to the end of the list. When clicked, a dialog will be shown to allow the user to select a colormap from the cmap catalog.

userAdditionsAllowed() -> bool

Returns whether the user can add custom colors.