public override void Perform(TextSearchEventArg arg){
     Presenter.ShowMessage("Search in files completed");
 }
 public override void Perform(TextSearchEventArg arg) {
     AddListItem("Text found", arg);
 }
 public override void Perform(TextSearchEventArg arg) {
     AddListItem("Warning", arg);
 }
 public abstract void Perform(TextSearchEventArg arg);
 protected void AddListItem(string status, TextSearchEventArg arg){
     Presenter.AddListItem(status, arg.FullFileName, arg.Message);
 }
 public override void Perform(TextSearchEventArg arg){
     Presenter.ShowMessage("Text to search is not specified");
 }