GeoDjango 表单 API

GeoDjango provides some specialized form fields and widgets in order to visually display and edit geolocalized data on a map. By default, they use OpenLayers-powered maps, with a base WMS layer provided by NASA.

字段参数

In addition to the regular form field arguments, GeoDjango form fields take the following optional arguments.

srid

Field.srid

This is the SRID code that the field value should be transformed to. For example, if the map widget SRID is different from the SRID more generally used by your application or database, the field will automatically convert input values into that SRID.

geom_type

Field.geom_type

You generally shouldn’t have to set or change that attribute which should be set up depending on the field class. It matches the OpenGIS standard geometry name.

表单字段类

GeometryField

class GeometryField

PointField

class PointField

LineStringField

class LineStringField

PolygonField

class PolygonField

MultiPointField

class MultiPointField

MultiLineStringField

class MultiLineStringField

MultiPolygonField

class MultiPolygonField

GeometryCollectionField

class GeometryCollectionField

表单部件

GeoDjango form widgets allow you to display and edit geographic data on a visual map. Note that none of the currently available widgets supports 3D geometries, hence geometry fields will fallback using a Textarea widget for such data.

表单属性

GeoDjango widgets are template-based, so their attributes are mostly different from other Django widget attributes.

BaseGeometryWidget.geom_type

The OpenGIS geometry type, generally set by the form field.

BaseGeometryWidget.map_height

BaseGeometryWidget.map_width

Height and width of the widget map (default is 400x600).

4.2 版后已移除: map_height and map_width attributes are deprecated, use CSS to size map widgets instead.

BaseGeometryWidget.map_srid

SRID code used by the map (default is 4326).

BaseGeometryWidget.display_raw

Boolean value specifying if a textarea input showing the serialized representation of the current geometry is visible, mainly for debugging purposes (default is False).

BaseGeometryWidget.supports_3d

Indicates if the widget supports edition of 3D data (default is False).

BaseGeometryWidget.template_name

The template used to render the map widget.

You can pass widget attributes in the same manner that for any other Django widget. For example:

from django.contrib.gis import forms
class MyGeoForm(forms.Form):
    point = forms.PointField(widget=forms.OSMWidget(attrs={"display_raw": True}))

部件类

BaseGeometryWidget

class BaseGeometryWidget

This is an abstract base widget containing the logic needed by subclasses. You cannot directly use this widget for a geometry field. Note that the rendering of GeoDjango widgets is based on a template, identified by the template_name class attribute.

OpenLayersWidget

class OpenLayersWidget

This is the default widget used by all GeoDjango form fields. template_name is gis/openlayers.html.

OpenLayersWidget and OSMWidget use the ol.js file hosted on the cdn.jsdelivr.net content-delivery network. You can subclass these widgets in order to specify your own version of the ol.js file in the js property of the inner Media class (see 资源作为静态定义).

OSMWidget

class OSMWidget

This widget uses an OpenStreetMap base layer to display geographic objects on. Attributes are:

• template_name

  gis/openlayers-osm.html

• default_lat

• default_lon

  The default center latitude and longitude are 47 and 5, respectively, which is a location in eastern France.

• default_zoom

  The default map zoom is 12.

The OpenLayersWidget note about JavaScript file hosting above also applies here. See also this FAQ answer about https access to map tiles.