A ExtJS paging toolbar component override to allow for showing/hiding the refresh button in the toolbar. Compatible with version Ext 4.2.1.

Paging.override.js

/**
 * A paging toolbar override to allow for hiding the refresh button in the toolbar. Compatible with Ext 4.2.1.
 *
 * @class Ext.toolbar.Paging
 * @override
 * @author Bostjan Rihter <bostjan.rihter@gmail.com>
 */
Ext.override(Ext.toolbar.Paging, {
  /**
  * @cfg {Boolean} enableRefresh
  * Set true to display the refresh button in toolbar, false to hide it.
  */
  enableRefresh: true,

  onLoad: function () {
    var me = this,
      pageData,
      currPage,
      pageCount,
      afterText,
      count,
      isEmpty,
      item;

    count = me.store.getCount();
    isEmpty = count === 0;
    if (!isEmpty) {
      pageData = me.getPageData();
      currPage = pageData.currentPage;
      pageCount = pageData.pageCount;
      afterText = Ext.String.format(me.afterPageText, isNaN(pageCount) ? 1 : pageCount);
    } else {
      currPage = 0;
      pageCount = 0;
      afterText = Ext.String.format(me.afterPageText, 0);
    }

    Ext.suspendLayouts();
    item = me.child('#afterTextItem');
    if (item) {
      item.setText(afterText);
    }
    item = me.getInputItem();
    if (item) {
      item.setDisabled(isEmpty).setValue(currPage);
    }
    me.setChildDisabled('#first', currPage === 1 || isEmpty);
    me.setChildDisabled('#prev', currPage === 1 || isEmpty);
    me.setChildDisabled('#next', currPage === pageCount || isEmpty);
    me.setChildDisabled('#last', currPage === pageCount || isEmpty);
    //#region override
    if (me.enableRefresh) {
      me.setChildDisabled('#refresh', false);
    }
    //#endregion
    me.updateInfo();
    Ext.resumeLayouts(true);

    if (me.rendered) {
      me.fireEvent('change', me, pageData);
    }
  },

  onLoadError: function () {
    if (!this.rendered) {
      return;
    }

    //#region override
    if (this.enableRefresh) {
      this.setChildDisabled('#refresh', false);
    }
    //#endregion
  },

  beforeLoad: function () {
    //#region override
    var me = this;
    if (me.rendered && me.enableRefresh) {
      me.setChildDisabled('#refresh', true);
    }
    //#endregion
  },

  getPagingItems: function () {
    var me = this,
      items;

    items = [{
      itemId: 'first',
      tooltip: me.firstText,
      overflowText: me.firstText,
      iconCls: Ext.baseCSSPrefix + 'tbar-page-first',
      disabled: true,
      handler: me.moveFirst,
      scope: me
    }, {
      itemId: 'prev',
      tooltip: me.prevText,
      overflowText: me.prevText,
      iconCls: Ext.baseCSSPrefix + 'tbar-page-prev',
      disabled: true,
      handler: me.movePrevious,
      scope: me
    },
  '-',
  me.beforePageText, {
    xtype: 'numberfield',
    itemId: 'inputItem',
    name: 'inputItem',
    cls: Ext.baseCSSPrefix + 'tbar-page-number',
    allowDecimals: false,
    minValue: 1,
    hideTrigger: true,
    enableKeyEvents: true,
    keyNavEnabled: false,
    selectOnFocus: true,
    submitValue: false,
    // mark it as not a field so the form will not catch it when getting fields
    isFormField: false,
    width: me.inputItemWidth,
    margins: '-1 2 3 2',
    listeners: {
      scope: me,
      keydown: me.onPagingKeyDown,
      blur: me.onPagingBlur
    }
  }, {
    xtype: 'tbtext',
    itemId: 'afterTextItem',
    text: Ext.String.format(me.afterPageText, 1)
  },
  '-', {
    itemId: 'next',
    tooltip: me.nextText,
    overflowText: me.nextText,
    iconCls: Ext.baseCSSPrefix + 'tbar-page-next',
    disabled: true,
    handler: me.moveNext,
    scope: me
  }, {
    itemId: 'last',
    tooltip: me.lastText,
    overflowText: me.lastText,
    iconCls: Ext.baseCSSPrefix + 'tbar-page-last',
    disabled: true,
    handler: me.moveLast,
    scope: me
  }];

    //#region override
    if (me.enableRefresh) {
      items.push('-');
      items.push({
        itemId: 'refresh',
        tooltip: me.refreshText,
        overflowText: me.refreshText,
        iconCls: Ext.baseCSSPrefix + 'tbar-loading',
        handler: me.doRefresh,
        scope: me
      });
    }
    //#endregion

    return items;
  }
});