用于几何体字段的AdminModelConvertor（LON/LAT）

Question

我想为Flask Admin创建一个视图，以便在几何体字段中输入坐标。如何创建两个textfield并将它们转换为Geometry对象？在

这是我迄今为止所做的（除了数不清的其他事情）

class CustomAdminConverter(AdminModelConverter):
    @converts('geoalchemy2.types.Geometry')
    def convert_geometry(self, field_args, **extra):
        return WayToCoordinatesField(**field_args)

class WayToCoordinatesField(wtf.TextAreaField):
    def process_data(self, value):
        print "run" #is never called??
        if value is None:
            value = {}
        else:
            value = "test"
        return value

class POIView(ModelView):
    inline_model_form_converter = MyInlineModelConverter
    model_form_converter=CustomAdminConverter
    can_create = True
    def __init__(self, session, **kwargs):
        # You can pass name and other parameters if you want to
        super(POIView, self).__init__(POI, session, **kwargs)

    def scaffold_form(self):
        form_class = super(POIView, self).scaffold_form()
        form_class.way = wtf.TextAreaField("Coordinates")
        return form_class

POI对象如下所示：

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非常感谢你的帮助！在

Answer 1

从Flask Admin的1.0.9版开始，它现在支持Geoalchemy2几何列（以及1.1.0中添加的geographic列）。在

最大的变化是从flask-admin.contrib.geoa导入ModelView，而不是flask-admin.contrib.sqla，因此一个简单的模型如下所示：

from geoalchemy2 import Geometry
from flask-admin.contrib.geoa import ModelView

app.config['MAPBOX_MAP_ID'] = 'example.abc123'    

class Location(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(64), unique=True)
    point = db.Column(Geometry("Point", 4326))

admin = Admin(app)
admin.add_view(ModelView(Location, db.session))

在列表视图中，将显示一个小的预览地图，然后显示一个传单。抽签在“编辑”或“创建视图”中查看。在

对于直线或复杂多边形，您可能需要用form_widget_args覆盖ModelView，以获得更合理大小的编辑空间。在

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Answer 2

找到了一个交互式地图的解决方案。 以下是我所做的：

管理员/py字段公司名称：

import json
from wtforms import Field
import geojson
from shapely.geometry import asShape
from geoalchemy2.shape import to_shape, from_shape
from wtforms.widgets import html_params, HTMLString
from geoalchemy2.elements import WKTElement, WKBElement
from flask import render_template
class WTFormsMapInput(object):
    def __call__(self, field, **kwargs):
        options = dict(name=field.name, value=field.data, height=field.height, width=field.width,
                       geometry_type=field.geometry_type)

        return HTMLString(render_template("admin/admin_map.html", height=options['height'], width=options['width'],
                                          geolayer=self.geolayer(field.data), preview=False))

    def geolayer(self, value):
        if value is not None:
            html = ""
            subme = """var geojson = JSON.parse('%s');
                       editableLayers.addData(geojson);
                       update()
                       map.fitBounds(editableLayers.getBounds());"""
            # If validation in Flask-Admin fails on somethign other than
            # the spatial column, it is never converted to geojson.  Didn't
            # spend the time to figure out why, so I just convert here.
            if isinstance(value, (WKTElement, WKBElement)):
                html += subme % geojson.dumps(to_shape(value))
            else:
                html += subme % geojson.dumps(value)
            return html


class WTFormsMapField(Field):
    widget = WTFormsMapInput()

    def __init__(self, label='', validators=None, geometry_type=None, width=500, height=500,
                 **kwargs):
        super(WTFormsMapField, self).__init__(label, validators, **kwargs)
        self.width = width
        self.height = height
        self.geometry_type = geometry_type

    def _value(self):
        """ Called by widget to get GeoJSON representation of object """
        if self.data:
            return self.data
        else:
            return json.loads(json.dumps(dict()))

    def process_formdata(self, valuelist):
        """ Convert GeoJSON to DB object """
        if valuelist:
            geo_ob = geojson.loads(valuelist[0])
            self.data = from_shape(asShape(geo_ob.geometry))
        else:
            self.data = None

    def process_data(self, value):
        """ Convert DB object to GeoJSON """
        if value is not None:
            self.data = geojson.loads(geojson.dumps(to_shape(value)))
            print self.data
        else:
            self.data = None

模板/管理员/管理员_地图.html在

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管理员/视图.py在

class POIView(ModelView):
    can_create = True
    form_overrides = dict(location=WTFormsMapField)
    form_args = dict(
        way=dict(
            geometry_type='Polygon', height=500, width=500
        )
    )
    column_formatters = dict(tags=lambda v, c, m, p: (u', '.join(u"=".join([k, v]) for k, v in m.tags.items())),
                             )

    def __init__(self, session, **kwargs):
        super(POIView, self).__init__(POI, session, **kwargs)

    def scaffold_form(self):
        form_class = super(POIView, self).scaffold_form()
        form_class.way = WTFormsMapField()
        form_class.tags = MySelect2TagsField("Tags",None)
        return form_class

管理员/模型.py在

class POI(db.Model):
    __tablename__ = 'zo_poi'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.Text())
    tags = db.Column(HSTORE())
    src = db.Column(db.Text())
    way = db.Column(Geometry('point', srid=4326))
    intern = db.Column(db.BOOLEAN())