Client side javascript, creation of several elements and show each asap

Question

Client side javascript code creates some elements (about 50-100) in a cycle:

for (var i = 0; i < list.length; i++) {
   var obj = document.createElement("DIV");
   obj.innerHTML = "<span class=\"itemId\">" + list[i].Id 
                   + "</span><!-- some more simple code --> ";

   mainObj.appendChild(obj);
}

There are some problems with browser rendering. For example, IE just freezes until it finishes the cycle, and then shows all elements at once. Is there a way to show each created element separately and immediately after appendChild()?

Answer 1

insert a delay between adding successive entries, with setTimeout().

function insertEntry(list, ix) {
    if (ix == null) {
        ix = 0;
    }
    else if (ix < list.length) {
        var elt= document.createElement("DIV");
        var attr = document.createAttribute('id');
        attr.value = 'item'+ix;
        elt.setAttributeNode(attr);
        elt.innerHTML = "<span class='itemCls'>" + list[ix].Id + ':&nbsp;' + list[ix].Name +
            "</span><!-- some more simple code -->\n";
        mainObj.appendChild(elt);
        ix++;
    }
    if (ix < list.length) {
        setTimeout(function(){insertEntry(list, ix);}, 20);
    }
}

Kick it off with:

    insertEntry(myList);

where myList is like this:

var myList = [
    { Id : '1938377', Name : 'Sven'},
    { Id : '1398737', Name : 'Walt'},
    { Id : '9137387', Name : 'Edie'}
    ...
 };

demo: http://jsbin.com/ehogo/4