当拖动透明的矩形四处移动时，光标可以经过多个可切换元素。

As you move the translucent rectangle around, the cursor moves over various swappable elements.

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前面，我提到过在可切换系统内有两种主要的交互元素：拖动元素的突出显示和拖动到的目标的突出显示。

Earlier, I mentioned that there were two major interactivity elements in the Swappable system: highlighting the dragged element and highlighting the drag target.

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另一个拖动处理程序highlighting_drag_handler负责突出显示鼠标移过的那些可切换元素，以显示可以进行元素拖动的地方。

The other drag handler, highlighting_drag_handler, is responsible for highlighting the swappable elements over which the cursor passes to show where you are permitted to drag the element.

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