Show markers on google maps dynamically -Rails 3.2 - ruby-on-rails

Question

i have a working code that shows multiple markers on google map using geocoder such as
#nearbys = Place.near("#{params[:address]}", 5,:order => "distance",:units => :km)
#nearbys.first(5)
and i display the markers using the below code
function initialize() {
var map;
var bounds = new google.maps.LatLngBounds();
var mapOptions = {
mapTypeId: 'roadmap'
};
// Display a map on the page
map = new google.maps.Map(document.getElementById("map-canvas-guest"), mapOptions);
map.setTilt(45);
// adding Multiple Markers from ruby object
var markers = [
['<%= #nearbys[0].title %>', '<%= #nearbys[0].latitude %>','<%= #nearbys[0].longitude %>'],
['<%= #nearbys[1].title %>', '<%= #nearbys[1].latitude %>','<%= #nearbys[1].longitude %>'],
['<%= #nearbys[2].title %>', '<%= #nearbys[2].latitude %>','<%= #nearbys[2].longitude %>'],
['<%= #nearbys[3].title %>', '<%= #nearbys[3].latitude %>','<%= #nearbys[3].longitude %>']
,
['<%= #nearbys[4].title %>', '<%= #nearbys[4].latitude %>','<%= #nearbys[4].longitude %>']
];
// adding Info Window Content
var infoWindowContent = [
['<div class="info_content" >' +
'<h3><%= #nearbys[0].title %></h3>' +'</br>'+
'<p><%= #nearbys[0].about %></p>' +
'</div>'],
['<div class="info_content">' +
'<h3><%= #nearbys[1].title %></h3>' +
'<p><%= #nearbys[1].about %></p>' +
'</div>'],
['<div class="info_content">' +
'<h3><%= #nearbys[2].title %></h3>' +'</br>'+
'<p><%= #nearbys[2].about %></p>' +
'</div>'],
['<div class="info_content">' +
'<h3><%= #nearbys[3].title %></h3>' +'</br>'+
'<p><%= #nearbys[2].about %>/p>' +
'</div>'],
['<div class="info_content">' +
'<h3><%= #nearbys[4].title %></h3>' +'</br>'+
'<p><%= #nearbys[4].about %></p>' +
'</div>']
];
// Display multiple markers on a map
var infoWindow = new google.maps.InfoWindow(), marker, i;
// Loop through our array of markers & place each one on the map
for( i = 0; i < markers.length; i++ ) {
var position = new google.maps.LatLng(markers[i][1], markers[i][2]);
bounds.extend(position);
marker = new google.maps.Marker({
position: position,
map: map,
title: markers[i][0]
});
// Allow each marker to have an info window
google.maps.event.addListener(marker, 'click', (function(marker, i) {
return function() {
infoWindow.setContent(infoWindowContent[i][0]);
infoWindow.open(map, marker);
}
})(marker, i));
// Automatically center the map fitting all markers on the screen
map.fitBounds(bounds);
}
// Override our map zoom level once our fitBounds function runs (Make sure it only runs once)
var boundsListener = google.maps.event.addListener((map), 'bounds_changed', function(event) {
this.setZoom(14);
google.maps.event.removeListener(boundsListener);
});
}//initialize ends
BUT the problem is:-what if #nearbys has less than 5 count,then this code fails.SO i have been trying to make it dynamic using jquery arrays but its not working because i think my code is missing something to work it dynamically.
it should be something like this..
var array=<%= #nearbys%>;
var markers=[];
var infowindows=[];
array.each(function(index){
markers.push('<%= #nearbys[0].title %>', '<%= #nearbys[0].latitude %>','<%= #nearbys[0].longitude %>');
infowindows.push('<div class="info_content" >'+'<h3><%= #nearbys[0].title %></h3>' +'</br>'+
'<p><%= #nearbys[0].about %></p>'+'</div>');
})
..SO how i can achieve this........to make this dynamic so that above working code doesnt breaks with the newly added code.

Answer 1

well after struggling with jquery arrays and json ,i was able to find this best solution...this is working in all scenarios and all i need is to handle empty and null conditions,which i already did and its working the way i needed.HOPE THIS HELPS SOMEONE
my controller
def show_nearby_locations
#nearbys = Place.near("#{params[:address]}", 5,:order => "distance",:units => :km)
#nearbys.first(10)
end
in my view file
<%= javascript_tag do%>
window.nearbys= <%=raw #nearbys.to_json %>;
<%end%>
this is my script inside view
function initialize() {
var map;
var bounds = new google.maps.LatLngBounds();
var mapOptions = {
mapTypeId: 'roadmap'
};
// Display a map on the page
map = new google.maps.Map(document.getElementById("map-canvas-guest"), mapOptions);
map.setTilt(45);
var markers=[];
var infoWindowContent=[];
$.each(nearbys, function(index) {
console.log( data[0][index].latitude,data[0][index].longitude );
markers.push([nearbys[index]['title'], nearbys[index]['latitude'],nearbys[index]['longitude']]);
infoWindowContent.push(['<div class="info_content" >' +
'<h3 style="color: rgb(<%= rand(0..200)%>,<%= rand(0..200)%> ,<%= rand(0..200)%>);">'+nearbys[index]['title']+'</h3>' +'</br>'+
'<p>'+nearbys[index]['about']+'</p>' +
'</div>']);
});
// Display multiple markers on a map
var infoWindow = new google.maps.InfoWindow(), marker, i;
// Loop through our array of markers & place each one on the map
for( i = 0; i < markers.length; i++ ) {
var position = new google.maps.LatLng(markers[i][1], markers[i][2]);
bounds.extend(position);
marker = new google.maps.Marker({
position: position,
map: map,
title: markers[i][0]
});
// Allow each marker to have an info window
google.maps.event.addListener(marker, 'click', (function(marker, i) {
return function() {
infoWindow.setContent(infoWindowContent[i][0]);
infoWindow.open(map, marker);
}
})(marker, i));
// Automatically center the map fitting all markers on the screen
map.fitBounds(bounds);
}
// Override our map zoom level once our fitBounds function runs (Make sure it only runs once)
var boundsListener = google.maps.event.addListener((map), 'bounds_changed', function(event) {
this.setZoom(14);
google.maps.event.removeListener(boundsListener);
});
}//initialize ends

Answer 2

Hello Friends by doing with Google Maps With Rails i have searched the information from google maps site and Gmaps4rails i have done Multiple Markers and Info-window her is the code
My Controller
#users = User.all
#hash = Gmaps4rails.build_markers(#users) do |user, marker|
marker.lat user.latitude
marker.lng user.longitude
marker.infowindow user.title`
end
In My View
window.onload = function () {
var markers = <%=raw #hash.to_json %>;
var mapOptions = {
center: new google.maps.LatLng(markers[0].lat, markers[0].lng),
zoom: 15,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
var infoWindow = new google.maps.InfoWindow();
var map = new google.maps.Map(document.getElementById("map"), mapOptions);
for (i = 0; i < markers.length; i++) {
var data = markers[i]
var myLatlng = new google.maps.LatLng(data.lat, data.lng);
marker = new google.maps.Marker({
position: myLatlng,
map: map,
title: data.title
});
(function (marker, data) {
google.maps.event.addListener(marker, "click", function (e) {
infoWindow.setContent(data.description);
infoWindow.open(map, marker);
});
})(marker, data);
}
}