Customizing "Choose Declaration" dialog

You can implement NavigationItem in the PSI elements you resolve to, and return custom presentation from getPresentation method. It probably won't look like in Show Usages, but the same information can be shown, maybe arranged in a bit different way.

Works like a charm, Thank you!

Just would like to notice for those who will be looking for a solution. All PsiElements already implement NavigationItem (from ancestor PsiElementBase). So we just need to implement getPresentation() method somehow like that:

public static ItemPresentation getPresentation() {
  return new ItemPresentation() {

    @Override
    public String getPresentableText() {
      return // Your text for the first column
    }

    @Override
    public String getLocationString() {
      return // Your text for the second, shadowed column 
    }

    @Override
    public Icon getIcon(boolean open) {
      return null; // Not used for dialog rendering :(
    }
  };
}