How to observe Android's Clipboard, really?

I need to detect Android Clipboard's content changes, and register the changes, but I can't really understand how to ac开发者_运维知识库hieve such result.

There are a lot of clipboard managers around, but I found none open source, and it's difficult to believe they work by checking the clipboard every 15 seconds.

Is there a good method to observe clipboard changes ?

Thanks in advance !

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Since API version 11 ("Android 3.0"), there is a new service and appropriate callback ClipboardManager.OnPrimaryClipChangedListener

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According to this thread, at least for the Clipper program, they do indeed poll the clipboard - every 5 seconds. There doesn't seem to be anything in the API to do it any other way.