code: function() {
  		var me = this;
  
  		if (me.showShowHideButton && me.columns.getCount()) {
  			var column = me.actionColumn || me.extraColumn;
  			var buttonEl = column.el.first().first();
  			me.showHideEl = Ext.get(Ext.core.DomHelper.append(buttonEl, {
  				tag: 'div',
  				style: 'position: absolute; width: 16px; height: 16px; top: 3px; cursor: pointer; left: ' + parseInt((column.el.getWidth() - 16) / 2) + 'px',
  				cls: me.showHideButtonIconCls,
  				'data-qtip': (me.renderHidden ? me.showHideButtonTooltipDo : me.showHideButtonTooltipUndo)
  			}));
  			me.showHideEl.on('click', function() {
  				me.setVisible(!me.isVisible());
  				me.showHideEl.set({
  					'data-qtip': (!me.isVisible() ? me.showHideButtonTooltipDo : me.showHideButtonTooltipUndo)
  				});
  			});
  		}
  
  		if (me.showClearAllButton && me.columns.getCount()) {
  			var column = me.actionColumn || me.extraColumn;
  			var buttonEl = column.el.first().first();
  			me.clearAllEl = Ext.get(Ext.core.DomHelper.append(buttonEl, {
  				tag: 'div',
  				style: 'position: absolute; width: 16px; height: 16px; top: 25px; cursor: pointer; left: ' + parseInt((column.el.getWidth() - 16) / 2) + 'px',
  				cls: me.clearAllButtonIconCls,
  				'data-qtip': me.clearAllButtonTooltip
  			}));
  
  			me.clearAllEl.hide();
  			me.clearAllEl.on('click', function() {
  				me.clearFilters();
  			});
  		}
      }
docs: private