ipyleaflet backend only renders a grey rectangle

[hydroEng]

Environment Information

• leafmap version: 0.11.3
• Python version: 3.10
• Operating System: Windows 10 (also tried on Linux

Description

Describe what you were trying to get done. Tell us what happened, what went wrong, and what you expected to happen.

What I Did

I'm trying to set up a web map using leafmap using the ipyleaflet backend (i.e. the default one).

Writing this in my IDE and running:

import leafmap

m = leafmap.Map(center=(40, -100), zoom=4)
m.to_html('leafmap.html')

Provides me a html with simply a grey box rather than showing the openstreetmap basemap. I've tried adding tile layers but I don't get much luck - for example, when adding ESRI world imagery, a lot of the tiles show as not available even though they work fine when using folium.

[giswqs]

What IDE?

[hydroEng]

Pycharm

The map displays correctly when using jupyter notebook. But even there when rendering to html I get the same problem.

[giswqs]

I have not used PyCharm with leafmap before. I guess this is an issue specific to PyCharm. Try the following code. If it doesn't work, then it is an ipyleaflet issue rather than leafmap.

import ipyleaflet m = ipyleaflet.Map() m

[hydroEng]

I used

import ipyleaflet

m = ipyleaflet.Map()
m.save('my_map.html', title='My Map')

And got the same result in the html. I guess this is an ipyleaflet issue... but thanks for your help anyway.

Somewhat off topic, would the folium backend support using ImageOverlay to plot a raster (using rasterio to bring in a tiff file as an array) and applying a colormap to it (also ignoring nodata values)? I can do all these things in folium itself, but the colormap comes out buggy.

I was hoping to use the ipyleaflet backend's ability to plot a .tiff directly.

[giswqs]

Yes, you can use m.add_raster() to load any local raster datasets. It supports both folium and ipyleaflet. It has parameters for custom if color maps.

[giswqs]

See https://leafmap.org/notebooks/32_local_tile/

[hydroEng]

Amazing. Thank you!