Returning value from ajax method to javascript method

Question

Hi,

I am trying to call a javascript method(fncApplicationAccess, which has a ajax call and resides in a .js file) from another javascript method "ShowWarning". I need to take decision in the "ShowWarning" javascript method with the return result from the fncApplicationAccess method.

function ShowWarning(appId, ctrl,act)
    {
        var appAccess = fncApplicationAccess(appId, ctrl,act);
        alert(appAccess);
        var mode;
        if (appAccess == "0") 
        {
            return false;
        }              
        else if (appAccess == "1")  // Request for Read Only 
        {
            // Read only not allowed
            return true;
        }
    }

When I execute, alert(appAccess) seems to be called much before the getting the value from the fncApplicationAccess.

Any help will be appreciated.