GeoFormAlchemy 0.3

Field modifications

The rendering of geometry fields can be customized with additional options. For example the following statement called on the field the_geom of the custom FieldSet changes the background map (inside the file your_app/forms/__init__.py):

Place = FieldSet(model.places.Place)
Place.the_geom.set(options=[
    ('map_srid', 900913),
    ('base_layer', 'new OpenLayers.Layer.OSM("OSM")')
])

The following options are available in GeoFormAlchemy:

default_lat and default_lon

If the geometry is None or when creating a new geometry, the map is centered at (default_lon, default_lat). Otherwise the map is centered at the centroid of the geometry.

zoom

The zoom-level on start-up.

map_width and map_height

The size of the DIV container in which the map is displayed.

base_layer

The OpenLayers layer which will be used as background map, for example:

('base_layer', 'new OpenLayers.Layer.OSM("OSM")')

map_srid

If the map uses a different CRS than the geometries, the geometries will be reprojected to this CRS. For example:

('map_srid', 900913)

openlayers_lib

The path to the OpenLayers JavaScript library, for example if OpenLayers.js is located at your_app/public/js/lib/OpenLayers.js use the following path:

('openlayers_lib', '/js/lib/OpenLayers.js')

show_map (default: True)

If show_map is set to False, the geometry will be displayed as WKT string inside a text input field.

Template files

If you want to change the look of your forms, you can modify the template files used by FormAlchemy and GeoFormAlchemy. The template files are located in the folder your_app/templates/forms.

GeoFormAlchemy uses the template files map_js.mako and map.mako. In map.mako you can set most of the options that you can also use as field modification. But unlike to field modifications, the options set in the template file are used for the geometry fields of all models, whereas the options set as field modification are only used for the field they were set on.

<%
# default configuration options that will be used when
# no field options were set

options = {}
options['default_lon'] = 10
options['default_lat'] = 45
options['zoom'] = 4
options['map_width'] = 512
options['map_height'] = 256
options['base_layer'] = 'new OpenLayers.Layer.WMS("WMS", "http://labs.metacarta.com/wms/vmap0", {layers: "basic"})'
options['openlayers_lib'] = 'http://openlayers.org/api/OpenLayers.js'

%>

If you want to customize the OpenLayers map, for example to add a further OpenLayers control or to add a second background layer, modify the file map_js.mako.