什么时候DOM更新完成，在javascript中添加子元素

在javascript中，我创建了放置在页面上的div。我得到左上角的宽度和高度为最后添加的元素放置新的。这些信息被保存到一个xml文件中，以便在重新加载页面时放置div。当我检索最后一个div的位置时，我得到的信息是从xml信息中放置的div的信息。换句话说，在javascript中创建的div似乎还没有在DOM中。是否有一个函数，我必须调用更新DOM ?

    var last_top = $('.linkcard:last', $("#page")).position().top;
    var last_left = $('.linkcard:last', $("#page")).position().left;
    var last_height = $('.linkcard:last', $("#page")).height();
    var last_width = $('.linkcard:last', $("#page")).width();

此代码在按钮的onClick事件中调用。第一次，它工作并检索静态div(从xml中检索的div)的信息。随后的几次，它没有检索到正确的信息，因为它似乎不知道在javascript中添加的div。我想，编写的代码会查看DOM中不知道新div的部分，对吗?我该怎么做才能得到正确的信息?

*完整的javascript函数*

function create_linkcard() {
    // Create LinkCard id
    var created_id_string = $.ajax({
        url: "create_id.php",
        type: "GET",
        data: { },
        cache: false,
        async: false,
        success: function (response) {
            if (response != '') 
            {
               /* alert(response); */
            }
        }
    }).responseText;
    var card_id = "c" + String(created_id_string);
    // Create Linkcard, add toolbar, resize #page
    $("#page").append('<div id="'+card_id+'" class="linkcard_init ui-widget-content" style="z-index: 9999;"></div>');
    $('#'+card_id).append('<p class="linkcard_header editableText">C'+created_id_string+'</p>');
    // Make edit box for LinkCard title
    $('#'+card_id).append('<form id="frm_name" name="frm_name" class="editableToolbar frm_add_linkcard"> <input type="text" placeholder="Type a name..." name="linkcard_name" class="txt_form"> <a href="#" title="Save" class="save btn_form" onClick="save_name('''+card_id+''', this.form); "></a> <a href="#" title="Cancel" class="cancel btn_form" onClick="delete_linkcard('+''''+card_id+''''+');"></a> </form>');
    // Add toolbar
    $('#'+card_id).append('<div class="toolbar"> <a href="#" title="Options" class="ico_tools"></a> <a href="#" title="Delete" class="ico_delete" onClick="delete_linkcard('+''''+card_id+''''+');"></a> </div>');
    // Add drag and drop box
    $('#'+card_id).append('<div class="link_drop_box"></div>');
    // Add scrolling buttons
    $('#'+card_id).append('<div class="scrolling_prev" title="Previous"></div>');
    $('#'+card_id).append('<div class="scrolling_next" title="Next"></div>');
    // Add search tool and add link tool
    $('#'+card_id).append('<div class="tools" > <a href="#" title="Add Link" class="ico_add" onClick="add_link('+''''+card_id+''''+');"></a> <a href="#" title="Search Links" class="ico_search" onClick="open_search('+''''+card_id+''''+');"></a> </div>');
    // Add script for scrolling
    $(document).ready(function($) {
        $(".scrolling_prev", $('#'+card_id)).mousedown(function() {
                        startScrolling($(".link_drop_box", $('#'+card_id)), "-=50px");
                    }).mouseup(function() {
                        $(".link_drop_box", $('#'+card_id)).stop()
                    });
        $(".scrolling_next", $('#'+card_id)).mousedown(function() {
                        startScrolling($(".link_drop_box", $('#'+card_id)), "+=50px");
                    }).mouseup(function() {
                        $(".link_drop_box", $('#'+card_id)).stop();
                    });
    }); 
    // Place new LinkCard
    /* var last_top = parseInt($('.linkcard:last', $("#page")).position().top);
    var last_left = parseInt($('.linkcard:last', $("#page")).position().left);
    var last_otop = parseInt($('.linkcard:last', $("#page")).offset().top);
    var last_oleft = parseInt($('.linkcard:last', $("#page")).offset().left);
    var last_height = parseInt($('.linkcard:last', $("#page")).height());
    var last_width = parseInt($('.linkcard:last', $("#page")).width()); */
    var last_top = parseInt($("#page").children('.linkcard:last').position().top);
    var last_left = parseInt($("#page").children('.linkcard:last').position().left);
    var last_otop = parseInt($("#page").children('.linkcard:last').offset().top);
    var last_oleft = parseInt($("#page").children('.linkcard:last').offset().left);
    var last_height = parseInt($("#page").children('.linkcard:last').height());
    var last_width = parseInt($("#page").children('.linkcard:last').width());
    alert ('top '+last_top+' left '+last_left+' offset top '+last_otop+' offset left '+last_oleft);
    var new_top = 0;
    var new_left = 0;
    /* if (last_left < 250) {
       new_top = last_top - last_height - last_height;
       new_left = last_left + last_width + 20;
    }
    else  {
       new_top = last_top - last_height + 20;
       new_left = 0;
    }*/
    if (last_left < 250) {
       new_top = last_top - last_height - last_height;
       new_left = last_left + last_width + 20;
    }
    else  {
       new_top = last_top - last_height + 20;
       new_left = 0;
    }
    // Define more LinkCard options
    $('#'+card_id).css('width',350);
    $('#'+card_id).css('height',250);
    $('#'+card_id).css('top',new_top);
    $('#'+card_id).css('left',new_left);
    $('#'+card_id).resizable();
    $('#'+card_id).draggable();
    $('#'+card_id).draggable("option", "handle", '.linkcard_header');
    $('#'+card_id+' p').editableText();
    $('#'+card_id).draggable({ stop: function(event, ui) { update_linkcard_xml(card_id) } });
    // Make droppable
    $('div.link_drop_box', $('#'+card_id)).droppable({
        drop: function( event, ui ) {
            var $item = ui.draggable;
            $item.fadeOut(function() {
                $item.css( {"left":"", "top":"", "bottom":"", "right":"" }).fadeIn();
            }); 
            $item.appendTo( this );
            /* update_links_xml("card_id"); */
       },
        out: function( event, ui ) {
            /* update_links_xml("card_id"); */ 
        },
        accept: ".link",
    });
    // Get LinkCard info for XML
    linkcard_name = $('#'+card_id).children('.linkcard_header').text();
    linkcard_top = $('#'+card_id).position().top;
    linkcard_left = $('#'+card_id).position().left;
    linkcard_width = $('#'+card_id).width();
    linkcard_height = $('#'+card_id).height();
    // Scroll LinkCard into view
    linkcard_offset = $('#'+card_id).offset().top+40;
    var scroll_top = parseInt(linkcard_top);
    alert (linkcard_offset);
    $('#matting').scrollTop(linkcard_offset);
    // Make ajax call to update XML
    $.ajax({
        url: "add_node.php",
        type: "POST",
        data: { nodeid: card_id, name: linkcard_name, top: linkcard_top, left: linkcard_left, width: linkcard_width, height: linkcard_height },
        cache: false,
        success: function (response) {
            if (response != '') 
            {
                /* alert(response); */
            }
        }
    });
}