Comments on: to_json and Rails 2

By: Michael

Michael — Fri, 09 Apr 2010 07:41:55 +0000

“var spots = ;”

is what I meant…

By: Michael

Michael — Fri, 09 Apr 2010 07:41:08 +0000

anybody who is trying to get the examples running on rails 3 beta:

rails 3 escapes erb by default. so make sure to use the raw method like this:

var spots = ;

By: Jeff

Jeff — Tue, 21 Apr 2009 02:23:29 +0000

Actually, never mind. I figured it out. Apparentally, the error I was getting was due to the loop that placed the markers on the map. I had to change the loop to look like:

for (i = 0; i < stores.length; i++) {
var store=stores[i].store;
addMarker(store.lat, store.lng, store.name);

}

By: Jeff

Jeff — Tue, 21 Apr 2009 01:53:36 +0000

I must admit that I’m a little confused, too, with regards to the example for 4-15. I’ve changed it from:

var stores=;
to
var stores=;

But it keeps giving me an “invalid argument” error. Any ideas?

By: Max Smart

Max Smart — Tue, 07 Apr 2009 07:16:42 +0000

I am using rails 2.2.2 and am only on chapter 3. I had to make this change to application.js

var marker=markers[i].attributes to var marker=markers[i].marker

and then it would pull the Markers already in the DB. Thanks, I am thrilled with this book.

PS I do have a question. If I only wanted to allow ONE geocach site what would you recommend. This is what I did, but do not think it is a good idea.
(the goal is to allow a user to select where they are from, but I only
want to capture and store a single geocode - no addresses can be stored in the system)

added to bottom of appl.js

function oneTime() {
removeListener(clicker)

}

window.onload = init;
window.onclick = oneTime;
window.onunload = GUnload;

in init() I changed the GEvent.addListener….

clicker = GEvent.addlistener…

By: Toby Seaman

Toby Seaman — Tue, 03 Mar 2009 23:35:17 +0000

joinlee, thanks for your August 16th post. I was completely stumped and unable to persuade my map to retrieve the points from the DB. I had pinned it down to a to_json type problem, but got lost working out how to debug. In the end it was a case of replacing .attributes with .marker. thank you so much for that gem!

By: chris

chris — Tue, 20 Jan 2009 03:22:34 +0000

You should link this from the errata– I only found this page after spending a bunch of time trying to figure out why listMarkers() in chapter 3 didn’t work and eventually figuring it out myself. I even came and looked at the errata page but it’s not there. I only got here after googling “rails to_json” once I realized there was a difference in the structure in the book vs. what I was getting back.

The upside: I learned more how to debug javascript and its interactions with rails.
the downside: it took more time than I would have liked because I don’t know much javascript and the way it deals with objects.

By: robert_d

robert_d — Fri, 26 Dec 2008 18:48:33 +0000

@jeremy
Put
var stores = ;
in map.html.erb (as it is explained above). Next see Page Source in a web browser to see what is the value of stores.

By: robert_d

robert_d — Thu, 25 Dec 2008 18:35:24 +0000

To see what Rails to_json function returns put this statement
in javascript file
alert(’request.responseText :’ + request.responseText);

By: jeremy

jeremy — Thu, 04 Dec 2008 19:17:24 +0000

I am trying to test your code in example 4-15 with rails 2.0.

I am seeing a syntax error when using json.

In your updated example: you said to change the code to var stores=; to var stores=;. This is the same thing. :) I also used the new update on this site and it is different.

var points=;

This is also throwing an error.