declare namespace Ext {
    export namespace dd {
        export interface DropTargetConfig {
            containerScroll?: boolean;
            ddGroup?: string;
            dropAllowed?: string;
            dropNotAllowed?: string;
            overClass?: string;
        }

        export class DropTarget extends Ext.dd.DDTarget  {
            public notifyDrop(source?: Ext.dd.DragSource, e?: Event, data?: object): boolean;
            public notifyEnter(source?: Ext.dd.DragSource, e?: Event, data?: object): string;
            public notifyOut(source?: Ext.dd.DragSource, e?: Event, data?: object): void;
            public notifyOver(source?: Ext.dd.DragSource, e?: Event, data?: object): string;
        }
    }
}