Android incoming call interception , call forwarding

I would like to know how to intercept incoming calls and also how to forward them. I know there are several questions regarding this topic here and elsewhere on the net, but all the answers use the android.intent.action.PHONE_STATE action which is broadcast always after the phone begins to ring and the call screen is shown.

That's why I'm looking for a solution where i could intercept the call in an early stage before 开发者_Python百科any notification (ringing etc..) has been done. I would like to know if maybe this is possible on a platform level in native code and if yes how ? Or perhaps with some kind of trick with the SDK ?

In general, if you can't do it in Java, you can't do it in the NDK. Most of the time the opposite is true: You can't do MOST things on Android in the NDK.

I don't know of a way to do that, and frankly doubt it exists: It would be a huge security hole if you could download an application that would forward calls to another number.

You may want to look at this source code, it may help you : http://code.google.com/p/auto-answer/

None of the existing apps in Android can forward a call based on a given number. All they can do is forward all or nothing. There's one app in particular (cBlocker) that can forward calls on schedule besides blocking incoming and outgoing calls and SMS based on rules.