Add a basic GeoAlchemy example.

examples/geo-alchemy/README.rst

+SQLAlchemy model backend integration examples.
+
+To run this example:
+
+1. Clone the repository::
+
+    git clone https://github.com/flask-admin/flask-admin.git
+    cd flask-admin
+
+2. Create and activate a virtual environment::
+
+    virtualenv env
+    source env/bin/activate
+
+3. Install requirements::
+
+    pip install -r 'examples/geo-alchemy/requirements.txt'
+
+4. Setup the database::
+
+    psql postgres
+
+    CREATE DATABASE flask_admin_geo;
+    CREATE ROLE flask_admin_geo LOGIN PASSWORD 'flask_admin_geo';
+    GRANT ALL PRIVILEGES ON DATABASE flask_admin_geo TO flask_admin_geo;
+    \q
+
+    psql flask_admin_geo
+
+    CREATE EXTENSION postgis;
+    \q
+
+5. Run the application::
+
+    python examples/sqla/app.py
+
+6. You will notice that the maps are not rendered. To see them, you will have
+to register for a free account at `Mapbox <https://www.mapbox.com/>`_ and set
+the *MAPBOX_MAP_ID* and *MAPBOX_ACCESS_TOKEN* config variables accordingly.
\ No newline at end of file

examples/geo-alchemy/app.py

+from flask import Flask
+from flask_sqlalchemy import SQLAlchemy
+
+import flask_admin as admin
+from geoalchemy2.types import Geometry
+from flask_admin.contrib.geoa import ModelView
+
+
+# Create application
+app = Flask(__name__)
+
+# Create dummy secrey key so we can use sessions
+app.config['SECRET_KEY'] = '123456790'
+
+app.config['SQLALCHEMY_DATABASE_URI'] = 'postgresql+psycopg2://flask_admin_geo:flask_admin_geo@localhost/flask_admin_geo'
+app.config['SQLALCHEMY_ECHO'] = True
+db = SQLAlchemy(app)
+
+app.config['MAPBOX_MAP_ID'] = "..."
+app.config['MAPBOX_ACCESS_TOKEN'] = "..."
+
+
+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"))
+
+
+# Flask views
+@app.route('/')
+def index():
+    return '<a href="/admin/">Click me to get to Admin!</a>'
+
+# Create admin
+admin = admin.Admin(app, name='Example: GeoAlchemy')
+
+# Add views
+admin.add_view(ModelView(Location, db.session))
+
+if __name__ == '__main__':
+
+    db.create_all()
+
+    # Start app
+    app.run(debug=True)

examples/geo-alchemy/requirements.txt

+Flask
+Flask-Admin
+Flask-SQLAlchemy
+shapely
+geoalchemy2
+psycopg2
\ No newline at end of file

examples/geo-alchemy/templates/admin/index.html

+{% extends 'admin/master.html' %}
+{% block body %}
+{{ super() }}
+<div class="row">
+  <div class="span10 offset1">
+    <h1>Flask-Admin example</h1>
+    <p class="lead">
+      GeoAlchemy model view.
+    </p>
+    <p>
+      This example shows how to manage spatial information in a GIS database.
+    </p>
+    <a class="btn btn-primary" href="/"><i class="icon-arrow-left icon-white"></i> Back</a>
+  </div>
+</div>
+{% endblock body %}