{
                    xtype: 'button',
                    text: 'GO',
                    itemId: 'prepare',
                    margin: '10 3 0 20',
                    handler : function() {
                        var form = this.up("form").getForm();
                        form.submit({
                            method: "POST",
                            submitEmptyText : false,
                            params : { __format: "ext" },
                            success: function(form, action) {
                                form.owner.up("panel").down("textareafield").setValue(action.result.config);
                            }
                        });
                    }
                    },
                    {
                    xtype: "textareafield",
                    name: 'config',
                    margin: '10 3 0 10',
                    flex: 1
                    }