Why remove all nodes occur bug

[nyr_jack]

var roots = $('#targetTree').tree('getRoots');
  for(var i = 0; i < roots.length; i++){
  $('#targetTree').tree('remove',roots.target);
}

Why occur bug with message '0.target is null or ...'

[sphsyv]

var roots = $('#targetTree').tree('getRoots');
  for(var i = 0; i < roots.length; i++){
  $('#targetTree').tree('remove',roots.target);
}

Why occur bug with message '0.target is null or ...'

当你remove第一个后，这个roots的索引就改变了，所以会出错。