Sample implementation for Badi CRM_IC_INBOX_BADI

Hi,

In our project we are going to extend Inbox Search with some custom fields in Search box.

But I have no idea about what should I write inside the BADI which works in background to take care of the searching.

I need all help that can be used for this implementation. Some questions are,

1. Do i need to alter Get_Query_Result method?

2. What should be the implementation inside of the other methods like BEFORE_SEARCH, AFTER_SEARCH?

3. Do I need to redefine any other methods.

4. Most imp, instead of implementing BADI, is there any other way around to provide solution to do this?