优质回答 回答者：void
A toast is a view containing a quick little message for the user. The toast class helps you create and show those.
When the view is shown to the user, appears as a floating view over the application. It will never receive focus. The user will probably be in the middle of typing something else. The idea is to be as unobtrusive as possible, while still showing the user the information you want them to see. Two examples are the volume control, and the brief message saying that your settings have been saved.
The easiest way to use this class is to call one of the static methods that constructs everything you need and returns a new Toast object.
android开发文档的解释，说白了就是弹出一个小信息，作为提醒用户或消息反馈来用，例如你发一条短信，弹出一个toast提示你消息已送达
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回答者：真相大白
toast是Android系统中一种消息框类型