GeoDjango 表单 API

GeoDjango 提供了一些专门的表单字段和小部件，以便在地图上可视化显示和编辑地理位置数据。默认情况下，它们使用由 NASA 提供的基本 WMS 图层，并由 OpenLayers 驱动的地图。

字段参数

除了常规的 表单字段参数 之外，GeoDjango 表单字段还接受以下可选参数。

srid

Field.srid

这是字段值应该转换为的 SRID 代码。例如，如果地图小部件的 SRID 与您的应用程序或数据库通常使用的 SRID 不同，该字段将自动将输入值转换为该 SRID。

geom_type

Field.geom_type

通常情况下，您不应该设置或更改该属性，它应该根据字段类进行设置。它与 OpenGIS 标准的几何名称相匹配。

表单字段类

GeometryField

class GeometryField[source]

PointField

class PointField[source]

LineStringField

class LineStringField[source]

PolygonField

class PolygonField[source]

MultiPointField

class MultiPointField[source]

MultiLineStringField

class MultiLineStringField[source]

MultiPolygonField

class MultiPolygonField[source]

GeometryCollectionField

class GeometryCollectionField[source]

表单部件

GeoDjango 表单小部件允许您在可视地图上显示和编辑地理数据。请注意，目前没有任何可用的小部件支持 3D 几何形状，因此对于这种类型的数据，几何字段将使用 Textarea 小部件作为回退。

表单属性

GeoDjango 的小部件是基于模板的，因此它们的属性大部分与其他 Django 小部件的属性不同。

BaseGeometryWidget.base_layer

New in Django 6.0.

A string that specifies the identifier for the default base map layer to be used by the corresponding JavaScript map widget. It is passed as part of the widget options when rendering, allowing the MapWidget to determine which map tile provider or base layer to initialize (default is None).

BaseGeometryWidget.geom_type

OpenGIS 几何类型，通常由表单字段设置。

BaseGeometryWidget.map_srid

地图使用的 SRID 代码（默认为 4326）。

BaseGeometryWidget.display_raw

布尔值，指定是否可见一个文本区域输入框，显示当前几何形状的序列化表示，主要用于调试目的（默认为 False）。

BaseGeometryWidget.supports_3d

指示小部件是否支持编辑 3D 数据的属性（默认为 False）。

BaseGeometryWidget.template_name

用于呈现地图小部件的模板。

您可以以与任何其他 Django 小部件相同的方式传递小部件属性。例如：

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[source]

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 base layer name, identified by the base_layer class attribute.

OpenLayersWidget

class OpenLayersWidget[source]

This is the default widget used by all GeoDjango form fields. Attributes are:

base_layer

New in Django 6.0.

nasaWorldview

template_name

gis/openlayers.html.

map_srid

3857

OpenLayersWidget and OSMWidget include the ol.js and ol.css files hosted on the cdn.jsdelivr.net content-delivery network. These files can be overridden by subclassing the widget and setting the js and css properties of the inner Media class (see 资源作为静态定义).

External assets with CSP

When ContentSecurityPolicyMiddleware is enabled, the default OpenLayers CDN assets (ol.js and ol.css) will be blocked unless explicitly allowed. This can be addressed in one of two ways: serve assets locally by subclassing the widget and provide local copies of the JavaScript and CSS files, or allow the CDN in the CSP policy.

For example, to allow the default NASA Worldview base layer (replace x.y.z with the actual version):

from django.utils.csp import CSP

SECURE_CSP = {
    "default-src": [CSP.SELF],
    "script-src": [CSP.SELF, "https://cdn.jsdelivr.net/npm/ol@x.y.z/dist/ol.js"],
    "style-src": [CSP.SELF, "https://cdn.jsdelivr.net/npm/ol@x.y.z/ol.css"],
    "img-src": [CSP.SELF, "https://*.earthdata.nasa.gov"],
}

OSMWidget

class OSMWidget[source]

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

base_layer

New in Django 6.0.

osm

default_lat

default_lon

默认的中心纬度和经度分别是 47 和 5，这是法国东部的一个位置。

default_zoom

默认的地图缩放级别是 12。

The OpenLayersWidget note about using external assets also applies here. See also this FAQ answer about https access to map tiles.

OpenStreetMap tiles with CSP

This widget uses OpenStreetMap tiles instead of NASA Worldview. If Content Security Policy enabled, both the OpenLayers CDN resources (as required by OpenLayersWidget) and the OpenStreetMap tile servers must be allowed:

from django.utils.csp import CSP

SECURE_CSP = {
    # other directives
    "img-src": [CSP.SELF, "https://tile.openstreetmap.org"],
}

Changed in Django 6.0:

The OSMWidget no longer uses a custom template. Consequently, the gis/openlayers-osm.html template was removed.

Customizing the base layer used in OpenLayers-based widgets

New in Django 6.0.

To customize the base layer displayed in OpenLayers-based geometry widgets, define a new layer builder in a custom JavaScript file. For example:

path-to-file.js

 MapWidget.layerBuilder.custom_layer_name = function () {
     // Return an OpenLayers layer instance.
     return new ol.layer.Tile({source: new ol.source.<ChosenSource>()});
 };

Then, subclass a standard geometry widget and set the base_layer:

from django.contrib.gis.forms.widgets import OpenLayersWidget


class YourCustomWidget(OpenLayersWidget):
    base_layer = "custom_layer_name"

    class Media:
        js = ["path-to-file.js"]