How to add a radius to a marker in Google-Maps-for-Rails?

问题

i am using the Google-Maps-for-Rails gem and I am now trying to display circles.

My Model "Place" consists of:

• longitude
• latitude
• radius
• etc

I have no problem to display markers:

# Controller: @markers = Place.all.to_gmaps4rails
gmaps("markers" => {"data" => @markers})

Unfortunately it doens't include :radius => .. I also know that circles can be displayed like:

gmaps(
"circles" => { "data" => '[
                         {"longitude": -122.214897, "latitude": 37.772323, "radius":1000000}
                         ]',
})

Is there any way to include the radius attribute in the markers hash ? Like:

gmaps("circles"     => { "data" => @markers })

Probably something like:

Place.all.each |place| place.merge!(:radius => 1000) ...

would do, but I think there may be a nicer solution

回答1:

The logic behind markers and circles is really different.

In your controller

@markers = Place.all.to_gmaps4rails
@circles = Place.all.map{|p| {:longitude => p.longitude, :latitude => p.latitude, :radius => p.radius}}.to_json

In your view:

<%= gmaps({ "markers" => {"data" => @markers},
           "circles" => {"data" => @circles}
          }) %>

Or if you don't need infowindow or other features, you could simply do:

In your controller

@circles = Place.all.map{|p| {:longitude => p.longitude, :latitude => p.latitude, :radius => p.radius}}.to_json

In your view:

<%= gmaps({ "markers" => {"data" => @circles},
           "circles" => {"data" => @circles}
          }) %>

来源：https://stackoverflow.com/questions/5719181/how-to-add-a-radius-to-a-marker-in-google-maps-for-rails