third_party/polymer/components-chromium/core-label/core-label-extracted.js

   1
   2     (function() {
   3
   4       var ID = 0;
   5       function generate(node) {
   6         if (!node.id) {
   7           node.id = 'core-label-' + ID++;
   8         }
   9         return node.id;
  10       }
  11
  12       Polymer('core-label', {
  13         /**
  14          * A query selector string for a "target" element not nested in the `<core-label>`
  15          *
  16          * @attribute for
  17          * @type string
  18          * @default ''
  19          */
  20         publish: {
  21           'for': {reflect: true, value: ''}
  22         },
  23         eventDelegates: {
  24           'tap': 'tapHandler'
  25         },
  26         created: function() {
  27           generate(this);
  28           this._forElement = null;
  29         },
  30         ready: function() {
  31           if (!this.for) {
  32             this._forElement = this.querySelector('[for]');
  33             this._tie();
  34           }
  35         },
  36         tapHandler: function(ev) {
  37           if (!this._forElement) {
  38             return;
  39           }
  40           if (ev.target === this._forElement) {
  41             return;
  42           }
  43           this._forElement.focus();
  44           this._forElement.click();
  45           this.fire('tap', null, this._forElement);
  46         },
  47         _tie: function() {
  48           if (this._forElement) {
  49             this._forElement.setAttribute('aria-labelledby', this.id);
  50           }
  51         },
  52         _findScope: function() {
  53           var n = this.parentNode;
  54           while(n && n.parentNode) {
  55             n = n.parentNode;
  56           }
  57           return n;
  58         },
  59         forChanged: function(oldFor, newFor) {
  60           if (this._forElement) {
  61             this._forElement.removeAttribute('aria-labelledby');
  62           }
  63           var scope = this._findScope();
  64           if (!scope) {
  65             return;
  66           }
  67           this._forElement = scope.querySelector(newFor);
  68           if (this._forElement) {
  69             this._tie();
  70           }
  71         }
  72       });
  73     })();
  74