    /**
     * @private
     * Private utility class for managing all {@link Ext.form.field.Checkbox} fields grouped by name.
     */
    Ext.define('Ext.form.CheckboxManager', {
        extend: 'Ext.util.MixedCollection',
        singleton: true,

        getByName: function(name, formId) {
            return this.filterBy(function(item) {
                return item.name == name && item.getFormId() == formId;
            });
        }
    });