prevent event bubble

[guaijie]

provide a way to prevent events from bubbling up

<Draggable
  className="drop-view"
  onDragStart="(v) => console.log('outer-drag-start:',  v)"
>
  <Draggable className="drag-item">1</Draggable>
  <Draggable className="drag-item">2</Draggable>
  <Draggable className="drop-view">
    <Draggable className="drag-item" onDragStart="(v) => console.log('inner-drag-start:',  v)"> 3</Draggable>
    <Draggable className="drag-item"> 4</Draggable>
  </Draggable>
</Draggable>

I want the child's onDragStart event to be triggered without the parent's onDragStart event being triggered at the same time, so that the parent event's behavior overrides the child event (because the child event fires first).