Appcelerator: Variable scope issue

Question

I am using the following code in Titanium Appcelerator to connect with remote Host:

var connect_remote = function(url)
{
    /*
     * make sure that the Device is connected before initiate process as we don't want to force
     * the user to open remote stream just for sake of new entries
     */
     //alert("In Func" + is_connected());
     var d_data = null;
     if(is_connected())
     {

         var c = Titanium.Network.createHTTPClient();
         var data = null;
         c.setTimeout(10000);
         c.onload = function()
            {
                if (c.status == 200 )
                {
                    data = this.responseData;
                    Titanium.App.Properties.setString('returnData',data);
                }
            };

        c.error = function(e)
        {
            alert("Error = "+e.error);
        }
        c.open('GET',url);
        c.send();
     }
}

I want to return the value of data variable which is supposed to keep the value of the response, so that I could use but it is always returning null or undefined. How do I return the value data from it?

Answer 1

It's not entirely clear what you mean, but I think you want your "connect_remote()" function to return some value to you. You can't do that in an asynchronous environment like yours. Instead, you can pass a function in to "connect_remote()" that can be passed the "data" value when the "onload" handler runs.

var connect_remote = function(url, handler)
{
    /*
     * make sure that the Device is connected before initiate process as we don't want to force
     * the user to open remote stream just for sake of new entries
     */
     //alert("In Func" + is_connected());
     var d_data = null;
     if(is_connected())
     {

         var c = Titanium.Network.createHTTPClient();
         var data = null;
         c.setTimeout(10000);
         c.onload = function()
            {
                if (c.status == 200 )
                {
                    data = this.responseData;
                    Titanium.App.Properties.setString('returnData',data);
                    handler(data);
                }
            };

        c.error = function(e)
        {
            alert("Error = "+e.error);
        }
            c.open('GET',url);
        c.send();
     }
}