COWMAN-CHIANG

• Using Json

  $('#using_json').jstree({ 'core' : 
  {
      'data' : [
          'Simple root node',
          {
              'text' : 'Root node 2',
              'state' : {
                  'opened' : true,
                  'selected' : true
              },
              'children' : [
                  { 'text' : 'Child 1' },
                  'Child 2'
              ]
          }
      ]
  } });
  

• Using the alternative JSON format

  $('#using_json').jstree({ 'core' : {
      'data' : [
          { "id" : "ajson1", "parent" : "#", "text" : "Simple root node" },
          { "id" : "ajson2", "parent" : "#", "text" : "Root node 2" },
          { "id" : "ajson3", "parent" : "ajson2", "text" : "Child 1" },
          { "id" : "ajson4", "parent" : "ajson2", "text" : "Child 2" },
      ]
  } });
  

Ref. Populating the tree using JSON

<input type="button" value="Expand All" onclick="$(‘#jsTreeID').jstree('open_all');">
<input type="button" value="Collapse All" onclick="$('#jsTreeID').jstree('close_all');">

Ref: jsTree: adding Expand All and Collapse All buttons