fixed copy, paste, cut bug when no buffer up

juci/notebook.cc

@@ -100,21 +100,29 @@ void Notebook::Controller::OnFileNewHeaderFile() {
   entry_.OnShowSetFilenName(".h");
 }
 void Notebook::Controller::OnEditCopy() {
-  std::cout << "Clicked copy" << std::endl;
+  if(view_.notebook().get_n_pages()!=0){
     int source_pos = view_.notebook().get_current_page();
-  Glib::RefPtr<Gtk::TextBuffer> buffer = source_vec_.at(source_pos)->view().get_buffer();
+    Glib::RefPtr<Gtk::TextBuffer> buffer = source_vec_.at(source_pos)
+      ->view().get_buffer();
     buffer->copy_clipboard(refClipboard);
   }
+}
 void Notebook::Controller::OnEditPaste() {
+  if(view_.notebook().get_n_pages()!=0){
     int source_pos = view_.notebook().get_current_page();
-  Glib::RefPtr<Gtk::TextBuffer> buffer = source_vec_.at(source_pos)->view().get_buffer();
+    Glib::RefPtr<Gtk::TextBuffer> buffer = source_vec_.at(source_pos)
+      ->view().get_buffer();
     buffer->paste_clipboard(refClipboard);
-};
+  }
+}
 void Notebook::Controller::OnEditCut() {
+  if(view_.notebook().get_n_pages()!=0){
     int source_pos = view_.notebook().get_current_page();
-  Glib::RefPtr<Gtk::TextBuffer> buffer = source_vec_.at(source_pos)->view().get_buffer();
+    Glib::RefPtr<Gtk::TextBuffer> buffer = source_vec_.at(source_pos)
+      ->view().get_buffer();
     buffer->cut_clipboard(refClipboard);
   }
+}