Add checkbox for each node, if set to true.
Examples
Material Design
<div id="tree"></div>
<script>
var tree = $('#tree').tree({
dataSource: '/Locations/Get',
checkboxes: true
});
</script>
Bootstrap 3
<div id="tree"></div>
<script>
var tree = $('#tree').tree({
dataSource: '/Locations/Get',
checkboxes: true,
uiLibrary: 'bootstrap'
});
</script>
Bootstrap 4
<div id="tree"></div>
<script>
var tree = $('#tree').tree({
dataSource: '/Locations/Get',
checkboxes: true,
uiLibrary: 'bootstrap4'
});
</script>