Disable all nodes from the tree.
Examples
Sample
<button onclick="tree.enableAll()" class="gj-button-md">Enable All</button>
<button onclick="tree.disableAll()" class="gj-button-md">Disable All</button>
<br/>
<div id="tree" data-source="/Locations/Get"></div>
<script>
var tree = $('#tree').tree({
checkboxes: true
});
</script>