I found this very good script which does exactly what I need, all i had to do was to comment a line. Congrats pushpontech for sharing his code:
Add the following in the treeview
onclick="OnTreeClick(event);"
And the rest in the javascript file
function OnTreeClick(evt) {
var src = window.event != window.undefined ? window.event.srcElement : evt.target;
var isChkBoxClick = (src.tagName.toLowerCase() == "input" && src.type == "checkbox");
if (isChkBoxClick) {
var parentTable = GetParentByTagName("table", src);
var nxtSibling = parentTable.nextSibling;
if (nxtSibling && nxtSibling.nodeType == 1)//check if nxt sibling is not null & is an element node
{
if (nxtSibling.tagName.toLowerCase() == "div") //if node has children
{
//check or uncheck children at all levels
CheckUncheckChildren(parentTable.nextSibling, src.checked);
}
}
//check or uncheck parents at all levels
//CheckUncheckParents(src, src.checked);
//This is the line which I had to comment in order to have the behaviour I needed
}
}
function CheckUncheckChildren(childContainer, check) {
var childChkBoxes = childContainer.getElementsByTagName("input");
var childChkBoxCount = childChkBoxes.length;
for (var i = 0; i < childChkBoxCount; i++) {
childChkBoxes[i].checked = check;
}
}
function CheckUncheckParents(srcChild, check) {
var parentDiv = GetParentByTagName("div", srcChild);
var parentNodeTable = parentDiv.previousSibling;
if (parentNodeTable) {
var checkUncheckSwitch;
if (check) //checkbox checked
{
var isAllSiblingsChecked = AreAllSiblingsChecked(srcChild);
if (isAllSiblingsChecked)
checkUncheckSwitch = true;
else
return; //do not need to check parent if any child is not checked
}
else //checkbox unchecked
{
checkUncheckSwitch = false;
}
var inpElemsInParentTable = parentNodeTable.getElementsByTagName("input");
if (inpElemsInParentTable.length > 0) {
var parentNodeChkBox = inpElemsInParentTable[0];
parentNodeChkBox.checked = checkUncheckSwitch;
//do the same recursively
CheckUncheckParents(parentNodeChkBox, checkUncheckSwitch);
}
}
}
function AreAllSiblingsChecked(chkBox) {
var parentDiv = GetParentByTagName("div", chkBox);
var childCount = parentDiv.childNodes.length;
for (var i = 0; i < childCount; i++) {
if (parentDiv.childNodes[i].nodeType == 1) //check if the child node is an element node
{
if (parentDiv.childNodes[i].tagName.toLowerCase() == "table") {
var prevChkBox = parentDiv.childNodes[i].getElementsByTagName("input")[0];
//if any of sibling nodes are not checked, return false
if (!prevChkBox.checked) {
return false;
}
}
}
}
return true;
}
//utility function to get the container of an element by tagname
function GetParentByTagName(parentTagName, childElementObj) {
var parent = childElementObj.parentNode;
while (parent.tagName.toLowerCase() != parentTagName.toLowerCase()) {
parent = parent.parentNode;
}
return parent;
}