Call a controller method from Javascript

Hey guys, I am trying to build an web app. I am running Rails 3. I just
want to make a call to a controller method from my javascript(view
part). Most of the links says AJAX. But I dont know whether its my
search part on the internet causing me problems, but I just could not
find a simple way of calling a Controller Method from Javascript.

My javascript function:
home.html.erb

function test_call(val)
{
alert(val);
new Ajax.Request(’/SessionsController/test_call_cont’, {
method: ‘post’,
parameters: {
menu_id: val,
}
});
}

And in my sessioncontroller.rb

def test_call_cont
puts “Printing from Controller”
end

Where am I going wrong, should I have to include any js files, or is my
syntax wrong? Totally confused.

Please do guide me.

Regards,
Nikhil

On 26 November 2012 09:27, nikhil rn [email protected] wrote:

function test_call(val)
{
alert(val);
new Ajax.Request(‘/SessionsController/test_call_cont’, {

Ajax.Request takes a url. Is ‘/SessionsController/test_call_cont’ a
valid url? Perhaps ‘/sessions/test_call_cont’ is what you want. Not
thought that you are not ‘calling a controller method’ but are
initiating a request on that url.

Colin

Hi Colin,
Im sorry but in the url, I am supposed to put up the path of my
controller method right?

Yes, my controller method is under main-application/app/views/sessions/.

So should I put it up like sessions/test_call_cont in the request? I
will also have to pass few parameters later on to that controller method
and render new page based on some operations in that controller
method(test_call_cont).

Regards,
Nikhil

On 26 November 2012 09:48, nikhil rn [email protected] wrote:

Hi Colin,
Im sorry but in the url, I am supposed to put up the path of my
controller method right?

Yes, my controller method is under main-application/app/views/sessions/.

You said earlier that the code is in sessions_controller.rb (actually
you said sessioncontroller.rb, but I assumed you meant
sessions_controller.rb) which should be in app/controllers, not
app/views.

So should I put it up like sessions/test_call_cont in the request?

Yes, you will also have to set up the route in routes.rb of course.

I
will also have to pass few parameters later on to that controller method
and render new page based on some operations in that controller
method(test_call_cont).

That is ok that is what controllers are for, but you should think of
it as an action, not a method (though it is a method of the controller
of course).

Colin

Colin,
Sorry again. It was a typing mistake I believe. My controller is
rightly placed in app/controllers. Though I have given the url as
/sessions/test_call_cont, Nothing seems to be happening. I am not
getting any error but neither I am getting the required output. Where
can I have gone wrong?

Nikhil

And I have also routed the method in the routes.rb. I have invoke that
url in routes.rb. But how can I achieve that from a javascript function
is my concern. Awaiting your thoughts on this.

Nikhil

No Colin. I kept track of line numbers in development.log . After I
make that click, there seems to be no action happening.

On 26 November 2012 10:16, nikhil rn [email protected] wrote:

Colin,
Sorry again. It was a typing mistake I believe. My controller is
rightly placed in app/controllers. Though I have given the url as
/sessions/test_call_cont, Nothing seems to be happening. I am not
getting any error but neither I am getting the required output. Where
can I have gone wrong?

Do you see anything in log/development.log when you make the call?

Colin

Just a quickshot, but is your javascript function really triggered when
clicking the link? Perhaps you could show that part of the view?
Am 26.11.2012 13:09 schrieb “nikhil rn” [email protected]:

If I put in an alert before the ajax call, the alert gets displayed.
This is what you meant you by triggering the javascript right?

On Nov 26, 2012, at 5:27 AM, nikhil rn wrote:

And I have also routed the method in the routes.rb. I have invoke that
url in routes.rb. But how can I achieve that from a javascript function
is my concern. Awaiting your thoughts on this.

Nikhil

What happens when you type that URL into a browser and try to visit it?
You should see something, unless your controller does not include any
handlers for a regular http request.

Walter

On 26 November 2012 12:19, nikhil rn [email protected] wrote:

parameters: {
  menu_id: val
}

});
}

Do you see an error if you run with a js debugger such as firebug in
firefox? That is assuming you have checked that you are including
prototype.js as suggested by Jim.

Colin

Jim ruther Nill wrote in post #1086470:

Are you sure that you’re using prototype?

Jim,

Yes I have put the latest prototype.js file in the
app/assets/javascripts folder.

Nikhil

On Mon, Nov 26, 2012 at 8:19 PM, nikhil rn [email protected] wrote:

parameters: {
  menu_id: val
}

});
}

Are you sure that you’re using prototype?

For more options, visit https://groups.google.com/groups/opt_out.

Walter D. wrote in post #1086483:

On Nov 26, 2012, at 5:27 AM, nikhil rn wrote:

What happens when you type that URL into a browser and try to visit it?
You should see something, unless your controller does not include any
handlers for a regular http request.

Walter

Walter,

When I hit the url, I found out I get this error:

Missing template sessions/test_call_cont, application/test_call_cont
with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder,
:coffee]}

Have I missed any template?

Nikhil

On Tue, Nov 27, 2012 at 12:32 PM, nikhil rn [email protected]
wrote:

Jim ruther Nill wrote in post #1086470:

Are you sure that you’re using prototype?

Jim,

Yes I have put the latest prototype.js file in the
app/assets/javascripts folder.

ok. Are you using the asset pipeline? Also, what browser are you
using?
I suggest you use chrome because it has a default developer tool. Look
at the js errors when you load the page. If there is nothing on the
log file and there’s no response on the page, it most likely is an error
with javascript.

To unsubscribe from this group, send email to
[email protected].
For more options, visit https://groups.google.com/groups/opt_out.

Jim,
Forgot to mention on asset pipeline. Sorry again, I did not get by what
you meant there.

Nikhil

Jim ruther Nill wrote in post #1086597:

ok. Are you using the asset pipeline? Also, what browser are you
using?
I suggest you use chrome because it has a default developer tool. Look
at the js errors when you load the page. If there is nothing on the
log file and there’s no response on the page, it most likely is an error
with javascript.

Jim,
I am using firefox 11. I am afraid I cant change my browser. And sorry,
how do I look for the js errors? I got nothing in the log file.

Nikhil

Walter,

The complete error message in my browser when the hit the URL is

Template is missing

Missing template sessions/test_call_cont, application/test_call_cont
with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder,
:coffee]}.

Searched in: * “/home/nikhil/nikhil_ror/main_application/app/views”

Have I given any wrong path?

Nikhil

Hey Guys, let me explain you all my scenario where I am stuck.

I got a table filled with cells. When I right click on any cell, I got
to display a context menu and then call a controller method on left
clicking the context menu. I got to send in a parameter to my controller
code and return what controller sends back. I am using jquery right
click for my context menu. I have the clicked cell value. I just need to
call a ruby controller method.

This is my home.html.erb code:

$(document).ready(function() {
var currentCellText;/this variable will have the clicked cell value/
$(“tbody td”).mousedown(function(e) {
currentCellText = $(this).text();

});

$.contextMenu({

    selector: '.context-menu-one',
    callback: function(key, options) {
        var m = "clicked: " + currentCellText;
       window.console && console.log(m)|| 

test_call(currentCellText);
},
items: {
“Menu 1”: {name: “Menu 1”},
“Menu 2”: {name: “Menu 2”},
}
});
});

function test_call(val)
{
alert(val);
new Ajax.Request(’/sessions/test_call_cont’, {
method: ‘post’,
parameters: {
menu_id: val
}
});
}

And my controller code is

def test_call_cont
puts “Printing from Controller”
end

Nikhil