extjs/packages/core/src/event/publisher/ElementPaint.js

   1 /**
   2  * @private
   3  */
   4 Ext.define('Ext.event.publisher.ElementPaint', {
   5
   6     extend: 'Ext.event.publisher.Publisher',
   7
   8     requires: [
   9         'Ext.util.PaintMonitor',
  10         'Ext.TaskQueue'
  11     ],
  12
  13     type: 'paint',
  14
  15     handledEvents: ['painted'],
  16
  17     constructor: function() {
  18         this.monitors = {};
  19         this.subscribers = {};
  20
  21         this.callParent(arguments);
  22     },
  23
  24     subscribe: function(element) {
  25         var me = this,
  26             id = element.id,
  27             subscribers = me.subscribers;
  28
  29         if (subscribers[id]) {
  30             ++subscribers[id];
  31         } else {
  32             subscribers[id] = 1;
  33
  34             me.monitors[id] = new Ext.util.PaintMonitor({
  35                 element: element,
  36                 callback: me.onElementPainted,
  37                 scope: me,
  38                 args: [element]
  39             });
  40         }
  41     },
  42
  43     unsubscribe: function(element) {
  44         var id = element.id,
  45             subscribers = this.subscribers,
  46             monitors = this.monitors;
  47
  48         if (subscribers[id] && !--subscribers[id]) {
  49             delete subscribers[id];
  50             monitors[id].destroy();
  51             delete monitors[id];
  52         }
  53     },
  54
  55     onElementPainted: function(element) {
  56         Ext.TaskQueue.requestRead('fire', this, [element, 'painted', [element]]);
  57     }
  58 }, function(ElementPaint) {
  59     ElementPaint.instance = new ElementPaint();
  60 });