Android ActivityGroup: pressing search button crashes app

I have a tab host, for each tab, an ActivityGroup is associated, and there are activities in each group, now I want to use search button, I followed Google's documentation, but when I press search button, I got an exception:

java.lang.IllegalArgumentException: no ident

My ActivityGroup subclass overrides onSear开发者_运维技巧chRequested() and calls current activity's onSearchRequested(), and my activity(inside ActivityGroup) overrides onSearchRequested() method, when it returns false, nothing appears and no crash, but when it returns true, the app crashes, does anyone know what the problem is?

Thanks!

In your Acyivity

@Override
  public boolean onSearchRequested(){
      return true;
  }