how create then trigger ajax action with D7 ajax API in js
yeah. thank askibinski so much!
in this post: XHR2 upload using Drupal 7's ajax framework

and this is my solution:

if($(viewDom).height() &lt; height ) {
    var element_settings = {};
    element_settings.progress = { 'type': 'none' }; 
    element_settings.event = "click";
    element_settings.setClick = false; 
    element_settings.url = Drupal.settings.views.ajax_path;
    element_settings.selector = viewDom;
    var setting = Drupal.settings.views.ajaxViews['views_dom_id:'+st.view_dom];
    setting.page = setting.page || 0;
    ++setting.page;
    element_settings.submit = setting;
    new Drupal.ajax(null, $(viewDom), element_settings).eventResponse($(viewDom)); 
    return;
}


and my real question is: how create then trigger ajax action with D7 ajax API in js

thank everybody alot.