declare namespace Ext {
    export namespace form {
        export interface CheckboxManagerConfig {
            allowFunctions?: boolean;
            defaultSortDirection?: string;
            listeners?: object;
            multiSortLimit?: number;
            sorters?: Ext.util.Sorter[] | object[];
            sortRoot?: string;
        }

        export class CheckboxManager extends Ext.util.MixedCollection  {
        }
    }
}