can/demos/can-stache-bindings/to-parent-function.html

MIT-licensed, client-side, JavaScript framework that makes building rich web applications easy.

<script type='text/stache' id='demo-html'>
	<my-tabs {^@add-panel}="@*addPanel">
	  <my-panel {add-panel}="@*addPanel" title="CanJS">CanJS Content</my-panel>
	  <my-panel {add-panel}="@*addPanel" title="StealJS">StealJS Content</my-panel>
	</my-tabs>
</script>
<script src="../../node_modules/steal/steal.js" main="@empty">
var Component = require("can-component");
var DefineMap = require("can-define/map/map");
var DefineList = require("can-define/list/list");
var canBatch = require("can-event/batch/batch");
var stache = require("can-stache");
	
Component.extend({
	tag: "my-tabs",
	template: 	
		stache("<ul>"+
			// Create an LI for each item in the panel's viewModel object
    		"{{#panels}}"+
    			"<li {{#isActive}}class='active'{{/isActive}} "+
    			    "($click)='makeActive(.)'>"+
    			  "{{title}}"+
    			"</li>"+
    		"{{/panels}}"+
    	"</ul>"+
    	"<content></content>"),
	ViewModel: DefineMap.extend({
		// Contains a list of all panel scopes within the
		// tabs element.
		panels: {
			value: new DefineList([])
		},
		active: "any",
		// When a `<panel>` element is inserted into the document,
		// it calls this method to add the panel's viewModel to the
		// panels array.
		addPanel: function(panel){
			// If this is the first panel, activate it.
			if(this.panels.length === 0) {
				this.makeActive(panel);
			} 
			this.panels.push(panel);
		},
		// When a `<panel>` element is removed from the document,
		// it calls this method to remove the panel's viewModel from
		// the panels array.
		removePanel: function(panel){
			var panels = this.panels;
			canBatch.start();
			panels.splice(panels.indexOf(panel),1);
			// if the panel was active, make the first item active
			if(panel === this.active){
				if(panels.length){
					this.makeActive(panels[0]);
				} else {
					this.active = undefined;
				}
			}
			canBatch.stop();
		},
		makeActive: function(panel){
			this.active = panel;
			this.panels.forEach(function(panel){
				panel.active = false;
			});
			panel.active = true;
		},
		// this is viewModel, not mustache
		// consider removing viewModel as arg
		isActive: function( panel ) {
			return this.active === panel;
		}
	})
});

Component.extend({
	template: stache("{{#if active}}<content></content>{{/if}}"),
	tag:"my-panel",
	ViewModel: DefineMap.extend({
		active: { value: false },
		addPanel: "any",
		init: function(){
			this.addPanel(this);
		}
	})
});

var el = document.getElementById("demo-html");
var frag = stache(el.innerHTML)({});

document.body.appendChild(frag);
</script>