I am trying to override the default image URLs without overwriting my theme's image files (as this will cause issues when upgrading the toolset). I have new images in a different folder and would like to assign them to _checkedImageURL, _uncheckedImageURL and _partialImageURL by default. Is there a way to do this?

Barring that I have created an init function which overrides the images on initialize. The problem with this code is that when a checkbox is in the unchecked state, the line var oTmpNode = oNodeList._items[nodeCounter]; returns undefined which means all checkboxes get reset properly except the unchecked ones. Code follows:

function setCheckboxImage(oNodeList, oTree) {
  if (oNodeList._items) {
    for (var nodeCounter = 0; nodeCounter < oNodeList._items.length; nodeCounter++) {
      var oTmpNode = oNodeList._items[nodeCounter];

      switch (oTmpNode.get_checkState()) {
        case 1:
          oTmpNode._get_checkBoxElement().src = oTree.Tree._checkedImageURL;
          break;
        case 2:
          oTmpNode._get_checkBoxElement().src = oTree.Tree._partialImageURL;
          break;
        default:
          oTmpNode._get_checkBoxElement().src = oTree.Tree._uncheckedImageURL;
          break;

    }

    if (oTmpNode._itemCollection) {
      setCheckboxImage(oTmpNode._itemCollection, oTree);
    }

  }

}
return true;
}

function wtFeatures_Initialize(sender, args) {

var oTree = igtree_getTreeById(m_wtFeaturesId);
oTree.Tree._checkedImageURL = "../css/ig_res/override/images/ig_checkbox_on.gif";
oTree.Tree._uncheckedImageURL = "../css/ig_res/override/images/ig_checkbox_off.gif";
oTree.Tree._partialImageURL = "../css/ig_res/override/images/ig_checkbox_partial.gif";

var oNodes = oTree.getNodes();
setCheckboxImage(oNodes,oTree);

}

Is there a bug here or am I missing something?