How to set a window loader param before the ajax call

Hi, i have a simple window, which is loading its contents automatically like this:

Code:

Ext.define('app.COMPONENTS.appVideoPlayer', {
                extend: 'Ext.window.Window',
                ,title: 'Video Player'
                ,modal: true
                ,closable: true
                ,resizable: true
                ,width: 800, height: 600
                ,autoShow: true
                ,loader:
                {
                    url: '/video/videocam_loader.html'
                    ,scripts: true
                    ,autoLoad: true
                    ,loadMask: true
                    ,params: { additionalParam: '' } 


                }
            
            ,initComponent: function()
            {
                var me = this;
                me.callParent(arguments);                
            }    
});

Now, i want upon the component creation (and before the loader's ajax call), to add an additional parameter to the loader's params like this:

Code:

Ext.create('app.COMPONENTS.appVideoPlayer', { paramToLoader:  'paramValue' });

So - before the ajax call, the params config to contain additionalParam: 'paramValue' Any suggestions?

In fact, i accomplished this via the beforeload listener within the loader config like this:

Code:

listeners: {
                        beforeload: function(loader, options) 
                        { 
                            options.params.additionalParam = loader.getTarget().paramToLoader; 
                        }    
               }

But - i'm not sure if this is right approach