KO可见不适用于模板

Question

Goal:

use KO to show/hide folder, sub-folder, and files, as recursive UL LI list. When a user click on the folders, the child items under that folder will toggle hide/show.

Problem:

The recursive part is ok. But it does not do toggle. console.log says error that 'show' is undefined. Any idea what went wrong ?

Code

<script type="text/javascript">

$(function() {
    ko.applyBindings(viewModel,document.getElementById('resources-panel'));
});

var viewModel = {
    treeRoot: ko.observableArray()
};

var FileElement = function(ppp_name, ppp_type, ppp_children) {
   var self = this;

   self.ppp_children = ko.observableArray(ppp_children);
   self.ppp_name = ko.observable(ppp_name);
   self.ppp_type = ko.observable(ppp_type);

   self.show = ko.observable(false);

    self.toggle=function() {
        self.show(!self.show());
    }

  }


var tree = [
    new FileElement("IT Dept", "folder",[
        new FileElement("IT Overview.docx", "file",[]),
        new FileElement("IT Server1", "folder",[
            new FileElement("IT Server1 Configuration Part 1.docx", "file", []),
            new FileElement("IT Server1 Configuration Part 2.docx", "file", []),
            ]),
        new FileElement("IT Server2", "folder",[])
        ]), 
    new FileElement("HR Dept", "folder", [])        
];

    viewModel.treeRoot(tree);

</script>

<script id="FileElement" type="text/html">
    <ul>
        <li>
            <a href="#" data-bind="click: toggle" class="action-link"><br/>
                <span data-bind="text: ppp_name"></span>
            </a>

        <ul data-bind="template: { name: 'FileElement', slideVisible: show, foreach: ppp_children }" ></ul>

        </li>
    </ul>
</script>    

<div id="resources-panel" data-bind="template: { name: 'FileElement', slideVisible: show, foreach: $data.treeRoot }"></div>

Answer 1

Your top level binding context is the treeRoot, and treeRoot doesn't have a "show" property it's just a simple array so you probably want to remove that first show binding altogether

<div id="resources-panel" data-bind="template: { name: 'FileElement', foreach: $data.treeRoot }"></div>

Then within the FileElement template you'll want to move the show binding to the outside of the template binding like f_martinez suggested

<ul data-bind="slideVisible: show, template: { name: 'FileElement', foreach: ppp_children }" ></ul>

Here's an example jsFiddle