diff -r 4ce98983666a -r 829abfdd6d27 src/pyams_gis/zmi/widget/area.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/pyams_gis/zmi/widget/area.py	Wed Jul 11 11:40:09 2018 +0200
@@ -0,0 +1,103 @@
+#
+# Copyright (c) 2008-2017 Thierry Florac <tflorac AT ulthar.net>
+# All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
+# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+# FOR A PARTICULAR PURPOSE.
+#
+
+__docformat__ = 'restructuredtext'
+
+
+# import standard library
+import json
+
+# import interfaces
+from pyams_form.interfaces.form import IFormLayer, IForm
+from pyams_gis.interfaces import IGeoArea
+from pyams_gis.interfaces.widget import IGeoAreaWidget
+from pyams_gis.schema import IGeoAreaField
+from pyams_utils.interfaces.data import IObjectData
+from z3c.form.interfaces import IFieldWidget, IObjectFactory
+
+# import packages
+from pyams_form.widget import widgettemplate_config
+from pyams_gis.area import GeoArea
+from pyams_utils.adapter import adapter_config
+from z3c.form.browser.object import ObjectWidget
+from z3c.form.object import getIfName
+from z3c.form.widget import FieldWidget
+from zope.interface import implementer_only, alsoProvides, Interface
+
+
+@adapter_config(name=getIfName(IGeoArea),
+                context=(Interface, IFormLayer, IForm, IGeoAreaWidget), provides=IObjectFactory)
+class GeoAreaObjectFactory(object):
+    """GeoArea object factory"""
+
+    def __init__(self, context, request, form, widget):
+        self.context = context
+        self.request = request
+        self.form = form
+        self.widget = widget
+
+    def __call__(self, data):
+        return GeoArea()
+
+
+@widgettemplate_config(mode='input', template='templates/geoarea-input.pt', layer=IFormLayer)
+@implementer_only(IGeoAreaWidget)
+class GeoAreaWidget(ObjectWidget):
+    """GeoArea widget"""
+
+    def updateWidgets(self, setErrors=True):
+        super(GeoAreaWidget, self).updateWidgets()
+        widgets = self.subform.widgets
+        x1 = widgets['x1']
+        x1.input_css_class = 'col-md-2'
+        x1.object_data = {'ams-change-handler': 'PyAMS_GIS.area.changedCoordinate'}
+        alsoProvides(x1, IObjectData)
+        x2 = widgets['x2']
+        x2.input_css_class = 'col-md-2'
+        x2.object_data = {'ams-change-handler': 'PyAMS_GIS.area.changedCoordinate'}
+        alsoProvides(x2, IObjectData)
+        y1 = widgets['y1']
+        y1.input_css_class = 'col-md-2'
+        y1.object_data = {'ams-change-handler': 'PyAMS_GIS.area.changedCoordinate'}
+        alsoProvides(y1, IObjectData)
+        y2 = widgets['y2']
+        y2.input_css_class = 'col-md-2'
+        y2.object_data = {'ams-change-handler': 'PyAMS_GIS.area.changedCoordinate'}
+        alsoProvides(y2, IObjectData)
+        projection = widgets['projection']
+        projection.object_data = {
+            'ams-events-handlers': {
+                'change.select2': 'PyAMS_GIS.area.changedProjection'
+            }
+        }
+        alsoProvides(projection, IObjectData)
+
+    @property
+    def wgs_coordinates(self):
+        value = self.field.get(self.field.interface(self.context))
+        if not value:
+            return json.dumps({'x1': None,
+                               'y1': None,
+                               'x2': None,
+                               'y2': None})
+        else:
+            point1, point2 = value.wgs_coordinates
+            return json.dumps({'x1': float(point1[0]),
+                               'y1': float(point1[1]),
+                               'x2': float(point2[0]),
+                               'y2': float(point2[1])})
+
+
+@adapter_config(context=(IGeoAreaField, IFormLayer), provides=IFieldWidget)
+def GeoAreaFieldWidget(field, request):
+    """GeoArea field widget factory"""
+    return FieldWidget(field, GeoAreaWidget(request))