Fix detached callback and add isAttached to SkyElements.

sky/framework/sky-element/sky-element.sky

Index: sky/framework/sky-element/sky-element.sky
diff --git a/sky/framework/sky-element/sky-element.sky b/sky/framework/sky-element/sky-element.sky
index 19eb2535f905aa53982923d5f77c242638ccd5eb..63ed363a4d55b9a3d38383e9d4255d5281c3392b 100644
--- a/sky/framework/sky-element/sky-element.sky
+++ b/sky/framework/sky-element/sky-element.sky
@@ -7,6 +7,15 @@
 <script>
 var templates = new Map();
 
+var kInternal = Symbol("SkyElementInternal");

[rafaelw, 2014/12/19 23:22:56]

nit: let's not use this kind of naming. How about 'internalSymbol'?

+
+class Internal {
+  constructor() {
+    this.appendedTemplate = false;
+    this.isAttached = false;
+  }
+};
+
 class SkyElement extends HTMLElement {
 
   static register() {
@@ -36,7 +45,7 @@ class SkyElement extends HTMLElement {
     // override
   }
 
-  dettached() {
+  detached() {
     // override
   }
 
@@ -49,23 +58,34 @@ class SkyElement extends HTMLElement {
   }
 
   createdCallback() {
+    this[kInternal] = new Internal();
     this.created();
   }
 
+  get isAttached() {
+    return this[kInternal].isAttached;
+  }
+
   attachedCallback() {
-    if (!this.shadowRoot) {
+    var internal = this[kInternal];
+
+    if (!internal.appendedTemplate) {
       var template = templates.get(this.localName);
       if (template) {
         var shadow = this.ensureShadowRoot();
         shadow.appendChild(template.createInstance(this));
         this.shadowRootReady();
+        internal.appendedTemplate = true;
       }
     }
+
     this.attached();
+    internal.isAttached = true;
   }
 
-  dettachedCallback() {
-    this.dettached();
+  detachedCallback() {
+    this.detached();
+    this[kInternal].isAttached = false;
   }
 
   attributeChangedCallback(attrName, oldValue, newValue) {