Deleting/Adding to DrawControl Doesn't Render on Map

[CF-FHB-X]

Hi there!

Just trying to understand how the relationship works between the Map and DrawControl. Our use case allows for users to create/edit/delete polygons by using the DrawControl tool. Each polygon gets a new ipywidgets.Tab (for adding attribute data) in an ipywidgets.VBox below the map.

What I'd like to do is also allow for creating/editing/deleting those polygons from the VBox (each Tab gets a "Delete" button, for example). Or I would like to programmatically add a polygon to the DrawControl when the user adds clicks something like a "Add Polygon" button.

Where I'm running into problems is that I can create/edit/delete the GeoJSON in the DrawControl.data list, but the map never changes. Am I missing a refresh option for either the Map or the DrawControl widget?

Thanks in advance!

[giswqs]

Relevant issue: #849

[davidbrochart]

@CF-FHB-X I'm suspecting you modify DrawControl.data in-place, for instance if you have:

dc.data = [{'type': 'Feature',
  'properties': {'style': {'stroke': True,
    'color': '#0000FF',
    'weight': 4,
    'opacity': 0.5,
    'fill': True,
    'fillColor': None,
    'fillOpacity': 0.2,
    'clickable': True}},
  'geometry': {'type': 'Polygon',
   'coordinates': [[[-78.290075, 34.622152],
     [-78.290075, 34.709432],
     [-78.111588, 34.709432],
     [-78.111588, 34.622152],
     [-78.290075, 34.622152]]]}}]

Then dc.data[0]["geometry"]["coordinates"][0][0][0] = -78.5 will not do anything. You need to assign to dc.data as a whole:

dc.data = [{'type': 'Feature',
  'properties': {'style': {'stroke': True,
    'color': '#0000FF',
    'weight': 4,
    'opacity': 0.5,
    'fill': True,
    'fillColor': None,
    'fillOpacity': 0.2,
    'clickable': True}},
  'geometry': {'type': 'Polygon',
   'coordinates': [[[-78.5, 34.622152],
     [-78.290075, 34.709432],
     [-78.111588, 34.709432],
     [-78.111588, 34.622152],
     [-78.290075, 34.622152]]]}}]

This is a limitation of traitlets.

[CF-FHB-X]

Ah-ha! That did it - thanks!