Dialog A
The content of Dialog A.
Dialog B
The content of Dialog B.
同时打开上面两个对话框，将一个拖动到使两个对话框稍稍重叠的位置。然后当你点击激活一个对话框，它就将显示于另一个之上了。
Open both dialogs and drag one of them to make them overlap a little bit. Then when you activate one dialog, it will be displayed on top of the other one.