Roll Polymer

third_party/polymer/v1_0/components-chromium/app-layout/app-scroll-effects/app-scroll-effects-behavior-extracted.js

 /**
    * `Polymer.AppScrollEffectsBehavior` provides an interface that allows an element to use scrolls effects.
    *
    * ### Importing the app-layout effects
    *
    * app-layout provides a set of scroll effects that can be used by explicitly importing
    * `app-scroll-effects.html`:
    *
    * ```html
    * <link rel="import" href="/bower_components/app-layout/app-scroll-effects/app-scroll-effects.html">
@@ skipping 115 matching lines @@
        * Disables CSS transitions and scroll effects on the element.
        */
       disabled: {
         type: Boolean,
         reflectToAttribute: true,
         value: false
       }
     },
 
     observers: [
-      '_effectsChanged(effects, effectsConfig)'
+      '_effectsChanged(effects, effectsConfig, isAttached)'
     ],
 
     /**
      * Updates the scroll state. This method should be overridden
      * by the consumer of this behavior.
      *
      * @method _updateScrollState
      */
     _updateScrollState: function() {},
 
@@ skipping 73 matching lines @@
         throw new ReferenceError(this._getUndefinedMsg(effectName));
       }
       var prop = this._boundEffect(effectDef, effectConfig || {});
       prop.setUp();
       return prop;
     },
 
     /**
      * Called when `effects` or `effectsConfig` changes.
      */
-    _effectsChanged: function(effects, effectsConfig) {
+    _effectsChanged: function(effects, effectsConfig, isAttached) {
       this._tearDownEffects();
 
-      if (effects === '') {
+      if (effects === '' || !isAttached) {
         return;
       }
       effects.split(' ').forEach(function(effectName) {
         var effectDef;
         if (effectName !== '') {
           if ((effectDef = Polymer.AppLayout._scrollEffects[effectName])) {
             this._effects.push(this._boundEffect(effectDef, effectsConfig[effectName]));
           } else {
             this._warn(this._logf('_effectsChanged', this._getUndefinedMsg(effectName)));
           }
@@ skipping 78 matching lines @@
     },
 
     /**
      * Overrides the `_scrollHandler`.
      */
     _scrollHandler: function() {
       if (!this.disabled) {
         this._updateScrollState(this._clampedScrollTop);
       }
     },
+    
+    /**
+     * Override this method to return a reference to a node in the local DOM.
+     * The node is consumed by a scroll effect.
+     *
+     * @param {string} id The id for the node.
+     */
+    _getDOMRef: function(id) {
+      this._warn(this._logf('_getDOMRef', '`'+ id +'` is undefined'));
+    },
 
     _getUndefinedMsg: function(effectName) {
       return 'Scroll effect `' + effectName + '` is undefined. ' +
           'Did you forget to import app-layout/app-scroll-effects/effects/' + effectName + '.html ?';
     }
 
   }];