Question

Is it possible to expand the first element of a tree (GUI) in google apps script? I can’t see any methods for that in the API https://developers.google.com/apps-script/class_tree

Answer 1

You can use the TreeItem method setState() to open a certain tree Item of a tree.

function OpenItem(e)
{
  var app = UiApp.getActiveApplication();
  app.getElementById('Item0').setState(true)
  return app;
}

Where the Item0 is the treeItem.

working example