IMO，至少有两种方法可以实现.您可以使用 JGlassPane 或

IMO there are at least two ways to achieve that. You can use JGlassPane or JXLayer framework. The basic idea to draw your popup messages on the transparent layer "above" your text fields.

我使用了JXLayer框架，因为我认为它为我提供了更大的灵活性.

I used the JXLayer framework because I felt it gave me a greater flexibility in what I could do.