SOURCE CODE: Uize.Comm.Iframe (view docs)

/*______________
|       ______  |   U I Z E    J A V A S C R I P T    F R A M E W O R K
|     /      /  |   ---------------------------------------------------
|    /    O /   |    MODULE : Uize.Comm.Iframe Class
|   /    / /    |
|  /    / /  /| |    ONLINE : http://www.uize.com
| /____/ /__/_| | COPYRIGHT : (c)2004-2016 UIZE
|          /___ |   LICENSE : Available under MIT License or GNU General Public License
|_______________|             http://www.uize.com/license.html
*/

/* Module Meta Data
  type: Class
  importance: 5
  codeCompleteness: 100
  docCompleteness: 50
*/

/*?
  Introduction
    The =Uize.Comm.Iframe= class implements support for communication to a server by submitting form data to it and targeting its response to an IFRAME.

    *DEVELOPERS:* `Chris van Rensburg`, `Jan Borgersen`, original code contributed by `Zazzle Inc.`

    In order to implement support for communication through an IFRAME, this class overrides the implementation of the =performRequest= instance method inherited from the =Uize.Comm= base class. There are no additional methods or properties provided by this class - all the interface is provided in the =Uize.Comm= superclass.
*/

Uize.module ({
  name:'Uize.Comm.Iframe',
  required:[
    'Uize.Url',
    'Uize.Dom.Basics'
  ],
  builder:function (_superclass) {
    'use strict';

    var
      /*** General Variables ***/
        _window = typeof window != 'undefined' ? window : {}
    ;

    /*** Some Setup ***/
      _window.handleResponse = function () {
        /*
          a dummy version of this function in case the user navigates back to a page using this code and a cached iframe server response tries to call this function (i.e. no requests have been made yet)
        */
      };

    return _superclass.subclass ({
      alphastructor:function () {
        /* NOTE:
          This puts the iframe in the page. Ideally, there should be a unique iframe per instance. The iframe insertion could even be deferred until the first request is performed.
        */
        var _iframeId = this.iframeId = 'Uize_Comm_Iframe_iframe' + Uize.Url.getCacheDefeatStr ();
        Uize.Dom.Basics.injectHtml (
          Uize.Dom.Basics.getById ('globalContent') || document.body,
          '<form id="CommIframe_form" style="display:none;" target="' + _iframeId + '" method="POST" accept-charset="utf-8">' +
            '<input id="CommIframe_params" name="params" type="hidden"/>' +
          '</form>' +
          '<iframe id="' + _iframeId + '" name="' + _iframeId + '" width="1" height="1" src="' + Uize.pathToResources + 'Uize/Comm/Iframe/blank.html" frameborder="1" style="position:absolute; visibility:hidden;" scrolling="no"></iframe>'
        );
      },

      instanceMethods:{
        performRequest:function (_request,_callback) {
          var
            _iframe = Uize.Dom.Basics.getById (this.iframeId),
            _requestUrl = Uize.Url.resolve (
              _request.url,
              {
                comm_mode:'ajax',
                output:'js',
                rnd:_request.cache == 'never' ? Uize.Url.getCacheDefeatStr () : null
              }
            ),
            _returnType = _request.returnType,
            _returnTypeIsObject = _returnType == 'object'
          ;
          _window.handleResponse = function (_responseResult) {
            if (_returnTypeIsObject || _returnType == 'json')
              _request.responseJson = Uize.clone (_responseResult)
            ;
            Uize.Dom.Basics.isIe && _iframe.contentWindow.history.go (-1);
            _callback ();
          };
          if (_request.requestMethod == 'POST') {
            var
              _form = Uize.Dom.Basics.getById ('CommIframe_form'),
              _paramsField = Uize.Dom.Basics.getById ('CommIframe_params'),
              _queryPos = _requestUrl.indexOf ('?')
            ;
            _paramsField.value = _queryPos > -1 ? _requestUrl.substr (_queryPos + 1) : '';
            _form.action = _requestUrl.slice (0,_queryPos);
            _form.submit ();
          } else {
            _iframe.src = _requestUrl;
          }
        }
      }
    });
  }
});