selectedIndex property
      
      int
      get
      selectedIndex
      
    
    
Gets or sets the selected index in the list.
Implementation
int get selectedIndex =>
    _helper.selectedIndexes.isEmpty ? -1 : _helper.selectedIndexes[0];
      
      set
      selectedIndex
      (int value) 
      
    
    
    
Implementation
set selectedIndex(int value) {
  _helper.selectedIndexes = <int>[value];
}