Getting nested set model into a
but hiding “closed” subtrees

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北海茫月 2020-12-14 13:02

Based on Getting a modified preorder tree traversal model (nested set) into a

One of answers gave right code to display full tree. What i need is to alway

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小蘑菇 (楼主)

2020-12-14 13:51
As you already managed to sort the sequence, why not just output as needed?

As some leafs need to appear closed, so the iterator should be able to skip children of non-selected nodes.

Doing so lead me to an idea to solve the problem of terminating the output tree (output = parsing). What to do if the last valid node in the sequence is at a higher depth than 0? I appended a NULL terminator for that. So still open levels can be closed before the loop finishes.

Additionally the iterator overloads nodes to offer common methods on them, like comparing against the currently selected element.

The MyRenderTree function (Demo/Full code)

Edit: The Demo Codepad has problems, here is the source-code: Gist Getting nested set model into a but hiding “closed” subtrees
```
function MyRenderTree($tree = array(array('name'=>'','depth'=>'', 'lft'=>'','rgt'=>'')) , $current=false)
{
    $sequence = new SequenceTreeIterator($tree);

    echo '';
    $hasChildren = FALSE;
    foreach($sequence as $node)
    {
        if ($close = $sequence->getCloseLevels())
        {
            echo str_repeat('
```

', $close);
            $hasChildren = FALSE;
        }
        if (!$node && $hasChildren)
        {
            echo '', "\n";
        }
        if (!$node) break; # terminator

        $hasChildren = $node->hasChildren();
        $isSelected = $node->isSupersetOf($current);

        $classes = array();
        $isSelected && ($classes[] = 'selected') && $hasChildren && $classes[] = 'open';
        $node->isSame($current) && $classes[] = 'current';

        printf('

%s', implode(' ', $classes), $node['name']); if ($hasChildren) if ($isSelected) echo ''; else $sequence->skipChildren() ; else echo '' ; } echo ''; }
This can be solved as well in a single foreach and some variables, however I think for re-useablilty, the implementation based on the SPL Iterators is better.

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Getting nested set model into a but hiding “closed” subtrees

Getting nested set model into a
but hiding “closed” subtrees