layer_slider

util.layer_slider(m, layers=None, pos=None, txt_patch_props=None, exclude_layers=None, name=None, **kwargs)

Get a slider-widget that can be used to switch between layers.

By default, the widget will auto-update itself if new layers are created!

Note

In general, layers are only drawn β€œon demand”, so if you switch to a layer that has not been shown yet, it needs to be drawn first.

  • Depending on the complexity (WebMaps, Overlays, very large datasets etc.) this might take a few seconds.

  • Once the layer has been drawn, it is cached and switching even between layers with many features should be fast.

  • If the extent of the map changes (e.g. pan/zoom) or new features are added to the layer, it will be re-drawn.

Parameters:

  • layers (list or None, optional) –

    A list of layer-names (or tuples of layer-names to combine) that are be used in the slider. For details on how to use combined layers, check the docstring of m.show_layer()

    If None, all available layers (except the β€œall” layer) are shown, and the layers are automatically updated whenever a new layer is created on the map. (check the β€˜exclude_layers’ parameter for excluding specific layers) The default is None.

  • pos (list or None, optional) – The position of the slider in figure-coordinates, provided as: (x0, y0, width, height). If None, the slider will be added at the bottom of the current axis. The default is None.

  • txt_patch_props (dict or None) –

    A dict used to style the background-patch of the text (e.g. the layer-names)

    For example:

    >>> dict(fc="w", ec="none", alpha=0.75, boxstyle="round, pad=.25")

    • If None, no background patch will be added to the text.

    The default is None.

  • exclude_layers (list or None) – A list of layer-names that should be excluded. Only relevant if layers=None is used. The default is None in which case only the β€œall” layer is excluded. (Same as exclude = [β€œall”]. Use exclude=[] to get all available layers.)

  • name (str) – The name of the slider (used to identify the object) If None, a unique identifier is used.

  • kwargs –

    Additional kwargs are passed to matplotlib.widgets.Slider

    The default is

    >>> dict(initcolor="none",
>>>      handle_style=dict(facecolor=".8", edgecolor="k", size=7),
>>>      label=None,
>>>      track_color="0.8",
>>>      color="0.2"
>>>      )

Examples

>>> from eomaps import Maps
>>> m = Maps(layer="coastline")
>>> m2 = m.new_layer(layer="ocean")
>>> m.add_feature.preset.coastline()
>>> m2.add_feature.preset.ocean()
>>> s = m.util.layer_slider(
>>>          layers=["ocean", "coastline",
>>>                  (("ocean", .5), "coastline")])

To remove the widget (s), simply use:

>>> s.remove()