toggleSearch method
      
void
toggleSearch()
      
     
    
    
Implementation
void toggleSearch() {
  if (isSearching) {
    searchController.text = '';
    isSearching = false;
    filter.search = '';
    filter.skip = 0;
    pagingController.refresh();
    return;
  }
  setState(() {
    isSearching = true;
    searchFocus.requestFocus();
  });
}