Nechápu, jako takto?
function MojeFunkce ()
{
var obj = {
items: [{
id: 45,
lable: "Test 1.2.1",
parent_id: 2
}, {
id: 12,
lable: "Test 1.0",
parent_id: 0
}, {
id: 32,
lable: "Test 1.1",
parent_id: 12
}, {
id: 2,
lable: "Test 1.2",
parent_id: 12
}]
}
var objDict = obj.items.reduce(function(p, c) {
p[c.id] = c;
c.children = [];
return p;
}, {});
var tree = obj.items.reduce(function(p, c) {
if (!c.parent_id) {
p = c;
} else {
objDict[c.parent_id].children.push(c);
}
return p;
}, {});
processTree(tree, document.getElementById("list"));
function processTree(node, element) {
var li = document.createElement('li');
li.innerText = node.lable;
element.appendChild(li);
if (node.children.length) {
var ul = document.createElement('ul');
li.appendChild(ul);
for (var i = 0; i < node.children.length; i++) {
processTree(node.children[i], ul);
}
}
}
}